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AbstractFuel-oil contamination of groundwater and waterways is common throughout the world. The fuel components methyl-tert-butyl ether (MTBE) and benzene, toluene, ethylbenzene and o-, p-and m-xylenes (BTEX) compounds are most likely to reach a borehole after a contamination event, and also those that pose the greatest risk.Various gas chromatography-mass spectrometry (GCMS) methods are available for the analysis of volatile organic compounds (VOCs) but many of these are not suitable for rapid and combined analysis of MTBE and BTEX. Here we describe and validate a simple and reliable method that fulfils these requirements. The method is quick: 48 samples can be analysed in a 24 hour period using the Precept II® autosampler and therefore is suitable for high throughput work. Validation of our experiments is presented in the form of linearity, precision and intra-day repeatability of standards as well as limits of detection and limits of quantification for the range 1—20 µg/l.This MTBE/BTEX analytical method developed was used to study the optimization of a modular post-abstraction remediation system incorporating air-stripping and granular activated carbon (GAC) technologies (Hall, 2004), from which a selection of sample data is presented.

Is your library's site trapped inside the frame of another organization's? Wonder how you can get out? This author details her experience of being caught in a government frame and tells you how you can break free. [ABSTRACT FROM AUTHOR]

All 24 secondary schools in a West Midlands local education authority were visited and a structured interview was conducted with the head or another senior teacher. An interview schedule was used to record details concerning the rule structure which had been established to control the conduct of the pupils. Information was also gathered about the sanctions and rewards used to maintain this behaviour and from most schools copies of the rules were available. It was found that almost all schools had rule systems that were in written form and that these were made available to staff and students, chiefly through booklets or other material given to pupils when they first enrolled. All schools backed up their rules, whether written or not by a series of sanctions, most of which related to non-conforming behaviour. Some sanctions were applied to poor work but this was usually treated by special provision or special tutoring. Most also used rewards but these tended to be reserved for good performance. There were few cases where good behaviour was found to be rewarded systematically in any way.

1. When Streptococcus faecium strain SY1 was established in the intestine of gnotobiotic chickens it depressed their growth.2. Dietary penicillin relieved the growth depression and caused a significant reduction in the count of S. faecium in the intestinal contents and in the number of bacteria attached to the duodenum wall.

Self Injurious Behaviour (SIB) refers to behaviour in which individuals attempt to self inflict physical damage to their tissues. It is a most disturbing behaviour to observe and one which is difficult to manage. This paper presents a functional analysis of the antecedents and consequences of the SIB of an intellectually retarded 17 year old male subject. The findings from a series of observations carried out are discussed in the light of three postulated theories of why individuals self injure. In conclusion recommendations are made as to the direction future research might take and also how staff working with the subject of this study might attempt to ameliorate his SIB.

A young child with an intellectual impairment was trained in a self management procedure in an attempt to ameliorate inappropriate classroom behaviours which were preventing his full integration into mainstream classes. A structured programme utilising countoons (stick figure drawings) to demonstrate specific behaviour to be self monitored was introduced in the special education facility where the participant received the majority of his education. Coloured stickers which were highly reinforcing were self administered by the participant when he exhibited the desired behaviours. Observations carried out in the special education facility and in a mainstream class to test for generalisation revealed reductions in the frequency of inappropriate behaviours in both settings. Follow up observations revealed behaviour maintenance in the special education facility whilst further reductions were recorded in the mainstream class.

To define an optimal regimen for mobilizing and collecting peripheral blood progenitor cells (PBPC) for use in allogeneic transplantation, we evaluated the kinetics of mobilization by filgrastim (recombinant met- human granulocyte colony-stimulating factor [r-metHuG-CSF]) in normal volunteers. Filgrastim was injected subcutaneously for up to 10 days at a dose of 3 (n = 10), 5 (n = 5), or 10 micrograms/kg/d (n = 15). A subset of volunteers from each dose cohort underwent a 7L leukapheresis on study day 6 (after 5 days of filgrastim). Granulocyte-macrophage colony-forming cell (GM-CFC) numbers in the blood were maximal after 5 days of filgrastim; a broader peak was evident for CD34+ cells between days 4 and 6. The 95% confidence intervals (CI) for mean number of PBPC per milliliter of blood in the three dose cohorts overlapped on each study day. However, on the peak day, CD34+ cells were significantly higher in the 10 micrograms/kg/d cohort than in a pool of the 3 and 5 micrograms/kg/d cohorts. Mobilization was not significantly influenced by volunteer age or sex. Leukapheresis products obtained at the 10 micrograms/kg/d dose level contained a median GM-CFC number of 93 x 10(4)/kg (range, 50 x 10(4)/kg to 172 x 10(4)/kg). Collections from volunteers receiving lower doses of filgrastim contained a median GM- CFC number of 36 x 10(4)/kg (range, 5 x 10(4)/kg to 204 x 10(4)/kg). The measurement of CD34+ cells per milliliter of blood on the day of leukapheresis predicted the total yield of PBPC in the leukapheresis product (r = .87, P < .0001). Assuming a minimum GM-CFC requirement of 50 x 10(4)/kg (based on our experience with autologous PBPC transplantation), all seven leukapheresis products obtained at the 10 micrograms/kg/d dose level were potentially sufficient for allogeneic transplantation purposes. We conclude that in normal donors, filgrastim 10 micrograms/kg/d for 5 days with a single leukapheresis on the following day is a highly effective regimen for PBPC mobilization and collection. Further studies are required to determine whether PBPC collected with this regimen reliably produce rapid and sustained engraftment in allogeneic recipients.

Brains of nine early and four advanced Alzheimer patients have been investigated, utilizing three approaches to specify the threshold state of Alzheimer's disease (AD). Extensive thin sectioning electron microscopy (EM) of frontal lobe biopsies, correlated with stringent clinical assessment, has demonstrated that the neuronal cytoskeleton undergoes specific transformations into paired helical filament-like (PHF-like) strands, which lead to the formation of the insoluble paracrystalline paired helical filaments (PHFs). The neurofilamentous network (NFN) transformation plays an important role in this process, whereby segregation, posttranslational modifications and reassembly of the modified components through autocrosslinking, and phase transition occur. According to our data, the threshold state can be defined as the state of irreversible segregation and posttranslational modification of the NFN and the microtubule-associated proteins. At this state, therapeutic intervention to reverse the disease process may be possible. The results indicate similarities between the formation of the paracrystals of the PHFs and the formation of the tropomyosin-like crystals of the Hirano bodies. Close relationships among PHFs and smooth endoplasmic reticulum and plasma membrane do exist. Enveloped virus-like particles have been observed in neurons containing PHFs. A possible role of these virus-like particles as an etiological agent for AD is discussed.

Using electron microscopy (EM), optical diffraction and image reconstruction techniques, we have demonstrated polymorphism of neurofilamentous network (NFN) in vitro based on phase transitions of the protein assemblies. The specific polymorphic appearances depended upon a number of factors, such as K +, Mg2 +, Ca2+ ions, as well as the charge and hydration state of the molecules. Furthermore, modifications initiated by the state of phosphorylation of the sidearm proteins played an important role, especially in determining the sidearm disposition of the NFN. The Ca2 +-activated protease removed the sidearms. Other enzymes activated by Ca2 + may initiate new association patterns of the peptide remnants and the intercoiling of two smooth neurofilaments (NFs) into paired helical filament-like (PHF-like) strands. Prolonged storage of the isolated NFs in Rubinson-Baker solution resulted in autocrosslinking and intercoiling of modified NFN components. The in vitro polymorphism and phase transitions of squid NFN induced under controlled conditions have been compared to modifications of cytoskeleton observed by EM in frontal lobe biopsies of Alzheimer patients. We conclude that similar processes, as induced in vitro, do occur in neurons of Alzheimer patients.

The "justification hypothesis" attributes mental retardation in phenylketonuria (PKU) to an inability of the heterozygous mother to deliver an appropriate amount of tyrosine to the PKU fetus who, in turn, is unable to correct for this deficiency because of its genetic constitution. We tested this hypothesis by measuring concentrations of tyrosine and phenylalanine in cord blood obtained at delivery from nine infants with PKU and five infants with persistent (non-PKU) hyperphenylalaninemia (PHP). For each of these specimens there were four control cord-blood specimens from infants born on the same day and, generally, in the same hospital. PKU and PHP groups were similar with respect to cord-blood tyrosine and phenylalanine values. There was no biologically significant deficiency of tyrosine in cord blood of the pooled PKU and PHP deficiency of tyrosine in cord blood of the pooled PKU and PHP groups (54 +/- 10 microM, mean +/- SD) compared with controls (61 +/- 16 microM, P = 0.13). On the other hand, phenylalanine in cord blood of the pooled PKU and PHP groups was significantly increased (144 +/- 30 microM, mean +/- SD) compared with controls (128 +/- 24, P = 0.004). The mangitude of the differences in cord-blood tyrosine and phenylalanine between control and PKU subjects are so small that it is unlikely that they have any consequences for physical and mental development. The justification hypothesis, as it pertains to blood tyrosine at term, is not upheld.

1. Chicks whose growth rate had been depressed either by a fully conventional flora or by association with a bile acid deconjugating strain of Streptococcus faecium and/or a filterable agent from chicken droppings showed no significant reduction in uptake of 3-O-methyl-a-D-glucopyranose compared with germ-free birds.2. Association with a microflora increased the weight of the gut per unit length.

Seventy‐three bacterial isolates from 65 horses with and without evidence of lower airway disease were identified to assess whether the association with disease was accounted for by a small or large number of species. Just over half (50.5 per cent were Actinobacillus equuli, 17.8 per cent were A suis‐like, 11 per cent were Pasteurella pneumotropica, 8.2 per cent were A lignieresii, 6.8 per cent were P haemolyticaand 5.5 per cent were P mairii. These results suggest that a range of Actinobacillusand Pasteurellaspecies can be isolated from the lower airways of horses, with many of the isolates being A equuli. Among the horses examined, lower airway inflammation was significantly associated with A suis‐like bacteria and A lignieresii. However, these two species constituted too small a proportion of the undifferentiated Actinobacillus/Pasteurellaspecies to explain the association of this group of bacteria with lower airway disease. Since A equuliconstituted just over 50 per cent of the group of bacteria it is possible that it too is playing a significant role in lower airway disease.