International statements and definitions of the precautionary principle

The precautionary principle (PP), according to one of its definitions, says that lack of certainty, given the current scientific and technological knowledge, shall not delay effective and proportionate actions to prevent hazards, taking into account cost-benefit considerations. Rather than being a single principle, a variety of statements of the PP are found in international treaties and other documents. Apart from any specific legal force of the documents, countries (e.g., France) have used these statements as a starting point for their own guidance documents and regulations for addressing specific environmental and health issues, for example regulation of genetically modified organisms. Thus, any discussion of the precautionary principle must address a complex legal and regulatory situation. We briefly review different statements of the PP and important commentary, largely from the European Union. We provide references to the original source documents (many of which are found in English on the World Wide Web).     

Properties of nanoporous organosilicate hybrid thin films with a bimodal pore size distribution

Low dielectric poly[methylsilsesquioxane‐ran‐trifluoropropylsilsesquioxane‐ran‐(2,4,6,8‐tetramethyl‐2,4,6,8‐tetraethylenecyclotetrasiloxane)silsesquioxane]s {P[M‐ran‐TFP‐ran‐(TCS)]SSQs} having various compositions were synthesized using trifluoropropyl trimethoxysilane, methyl trimethoxysilane and 2,4,6,8‐tetramethyl‐2,4,6,8‐tetra(trimethoxysilylethyl)cyclotetrasiloxane. The chemical composition of the polymers and the content of SiOH end‐groups were controlled by adjusting the reaction conditions, and they were characterized by ¹H‐NMR. The thermally decomposable trifluoropropyl groups on the P[M‐ran‐TFP‐ran‐(TCS)]SSQ backbone and heptakis(2,3,6‐tri‐O‐methyl)‐β‐cyclodextrin (CD) were employed as pore generators. The dielectric constants of the porous CD/P[M‐ran‐TFP‐ran‐(TCS)]SSQ films were in the range 2.0–2.7 (at 100 kHz) depending on the concentration of the porogens, and showed no change over 4 days under aqueous conditions. The pore size of the films showed a bimodal distribution, with diameters of ca 0.5–1.0 nm for those originating from the trifluoropropyl groups and 1.7 nm from the CD. The elastic modulus and hardness of the 30 vol% CD‐blended film with a dielectric constant of 2.26 were 2.40 and 0.38 GPa, respectively, as determined by a nanoindenter. Copyright © 2005 Society of Chemical Industry     

Acquired hemophilia and rheumatoid arthritis. Value of intravenous immunoglobulins

The authors report an exceedingly rare complication of rheumatoid arthritis, i.e. acquired hemophilia due to anti-factor VIII autoantibody production. Treatment with intravenous immune globulin ensured control of hemorrhagic manifestations by inducing a transient rise in factor VIII level.     

Comparative fate of 1,1-diphenylethylene (DPE), 1,1-dichloro-2,2-bis(4-Chlorophenyl)-ethylene (DDE), and pentachlorophenol (PCP) under alternating aerobic and anaerobic conditions

First, annual cost of electronic filing of medical images were calculated and compared with that of film storage in two hospitals under different conditions. Storage of medical images using a pixel size of 100 microns x 100 microns and 2-byte depth on the 130 mm, 650 MB magneto-optical disks costs with four times as much as the cost for film storage. However, 175 microns x 175 microns 12 bits combined with implementation of lossless compression would reduce the cost to a level equal to that for films storage. Doubled or tripled densities of MOD will improve the cost ever further. Second, the effectiveness of Hospital Information System/Radiological Information System (HIS/RIS) was evaluated. Examination time, film delivery time and the total turn-around time was markedly shortened by more than 23 hours on average. Our measurement method employing IC cards in pre-post HIS/RIS/PACS procedures is generally applicable to other hospitals. Third, to determine the optimal method of maximizing the efficacy of diagnostic imaging, 260 questionnaires were sent to the staff of 13 university hospitals. Every situation was described by both a radiologist and the physician who ordered the examination and received the reports and images. The level of technical efficacy and diagnostic accuracy of radiology strongly influenced the diagnostic thought processes of the physician.     

An expert decision support system for network routing: a case study

The paper presents a case study of the development of an expert decision support system which uses simple heuristic methods for fast determination of routes for simultaneous signals in a transmission network of limited capacity. It illustrates how heuristic solutions can be embodied in a model-based DSS and how the standard decision support literature, although intuitively appealing, provides little practical assistance in system construction or classification     

Efficacy of monensin for the prevention of subclinical ketosis in lactating dairy cows

A total of 1010 dry cows and pregnant heifers was randomly selected from 25 dairy farms near Guelph, Ontario, Canada to receive either a controlled-release capsule of monensin or a placebo at 3 wk prior to expected calving. Serum samples were obtained at the time of treatment administration, and both serum and milk samples were collected at wk 1, 2, 3, 6, and 9 postcalving. The threshold used to define subclinical ketosis was selected a priori at a concentration of > or = 1200 mumol/L of beta-hydroxybutyrate. Using this threshold, the prevalence and incidence of subclinical ketosis were significantly reduced (50%) by monensin treatment. The duration of subclinical ketosis for cows that had been treated with monensin was also shorter than that for cows treated with the placebo. Monensin treatment significantly reduced the incidence of subclinical ketosis when the threshold was defined using higher concentrations of serum beta-hydroxybutyrate (1400 and 2000 mumol/L). In addition, monensin significantly reduced the prevalence of positive milk ketone tests.