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This study aimed to increase the knowledge on the influence of alkaline cleaning on performance of polyamide based nanofiltration membranes. In the experiments the Desal-5 DL, XN45 and NF270 membranes were exposed to alkaline conditions at temperatures of 40, 50, 60 and 70 °C and the influence of the extended alkaline exposure to the membrane permeability, glucose and MgSO 4 retention was measured. The characteristic features of the experimental kinetic data for permeability were a rapid increase in permeability after a short time exposure and a subsequent steady increase when the exposing time was continued while the characteristic features for the retention data were a rapid decrease in retentions of glucose and MgSO 4 after a short time exposure and a subsequent steady decrease when the exposing time was continued. The model developed in this study described well the both rapid and slow changes and it can be used to predict the performance of the tested membranes at the temperature range between 40 and 60 °C. The increase in exposure temperature accelerated the changes in membrane performance. The alkali induced changes caused at the 70 °C exposure could not be described with the simple rate law. However, only minor changes in chemical structure of the membranes were noticed in IR spectra after the exposure to alkaline conditions at 70 °C. This indicates that changes observed in permeability and retention could mainly be linked to conformational changes occurring in the polymeric matrix of the membrane skin layers. It was also shown that after a relatively long recovery time (144.5 h) the alkali induced changes in membrane performances were at least partly recovered.

v d i v t T spine, being the main stabilizing and weight-bearing structure of the axial skeleton, is commonly injured in high-energy accidents. The predominant cause of serious injury with spinal involvement in the industrialized world are blunt deceleration trauma from a motor vehicle accident (MVA) or fall from a height.1,2 Additionally, the increasing popularity of xtreme and contact sports, as well as other activities prone to high-speed/ igh-impact events on a professional or an amateur or leisure level, contribtes to the incidence of high-energy blunt deceleration trauma.2 Although ata on developing countries are scarce and documentation is commonly acking, the leading causes of traumatic spinal injury seem to correspond losely to those in the developed world. Areas with similar economies tend to ave similar patterns of injury.1 Before the advent of computed tomography (CT), radiographic exclusion of spinal injury was performed mainly by plain radiography, including multiple views of the cervical spine. Conventional tomography improved on this technique, with the x-ray tube and film being moved in opposite directions during exposure. This puts a predetermined plane into sharp focus and blurs all other layers. Conventional tomography remained a cornerstone of diagnostic imaging for the evaluation of deep structures otherwise invisible on radiographs owing to summation, until it was made obsolete by the introduction of CT. With the resolution and reformatting capabilities of modern multidetector computed tomography (MDCT) scanners combined with rapid acquisition times, MDCT is the gold standard for the exclusion of spinal injury. Only in the event of a suspected ligamentous injury without involvement of bony structures does magnetic resonance imaging (MRI) perform better because of its inherent soft-tissue contrast.3

The results of selective oxidation of CH3OH and CH3SH to produce formaldehyde are presented and the effect of the reaction conditions on the CH2O yield is evaluated. The yield of formaldehyde was evaluated by thermodynamic calculations by using the HSC Chemistry® and Aspen Plus® simulation programmes. Oxidation of CH3OH and CH3SH was investigated by calculating the system equilibrium composition. Based on the modelling results, the yield of formaldehyde was almost zero with all the reactants present, i.e. the CH3OH, CH3SH and CH3OH + CH3SH mixture, which was also supported by the experiments. Catalytic experiments were performed over TiO2, V2O5/SiO2 and V2O5/(SiO2 + 10% TiO2) catalysts to evaluate the effect of feed concentration, reaction temperature and catalyst loading on the formaldehyde yield. Both CH3OH and CH3SH were oxidized separately and as mixtures. The V2O5/(SiO2 + 10% TiO2) catalyst was the most active catalyst in formaldehyde production. At optimal reaction conditions, 88% yield of CH2O was achieved at 413 °C in a feed mixture of 1000 ppm of CH3OH + CH3SH with the space velocity of 94,000 h−1. The catalysts showed no activity loss when tested for 6 h.

Summary Purpose To characterize the clinical features and molecular genetic background in a family with various epilepsy phenotypes including febrile seizures, childhood absence epilepsy, and possible temporal lobe epilepsy. Methods Clinical data were collected. DNA and RNA were extracted from peripheral blood. A genome-wide microsatellite marker scan was performed and regions with a multipoint location score ≥1.5 were fine mapped. Functional candidate genes identified from databases and by comparing gene expression profiles of genes between affected and unaffected individuals were sequenced. Copy number variation was evaluated with array-based comparative genomic hybridization. Results The seizure phenotype was benign. Inheritance was consistent with an autosomal dominant model and reduced penetrance. The highest two-point LOD score of 2.8 was identified at marker D17S1606 in a 37cM interval on chromosome 17q12-q24. Loci on 5q11.2 and on 18p11-q11, showed LOD scores ≥1.5 after fine mapping. Sequencing of nine ion-channel genes and two ( RPIP8 and SLC25A39 ) differentially expressed genes from 17q12-q24, as well as IMPA2 from 18p11-q11 did not reveal a pathogenic alteration. No clinically relevant copy number variation was identified. Conclusions Our findings suggest complex inheritance of seizure susceptibility in the family with contribution from three loci, including a possible new locus on chromosome 17q. The underlying molecular defects remain unknown.

Xylose is an intermediate product in xylitol production. Nanofiltration could simplify and enhance this separation step conventionally done by chromatographic methods. Here different hemicellulose hydrolyzate feeds were nanofiltered to recover xylose into the permeate. Two different batches of hemicellulose hydrolyzate were prepared: the hydrolyzate as such and modified with crystalline xylose addition. Both feed solutions were diluted to a total dry solids (TDS) content of approximately 21 wt.% and the xylose contents were 48.7% and 59.1% of the TDS f (total dry solids in feed). The filtration experiments were made at 40, 50 and 60 °C in total reflux mode for approximately 30 min at each pressure of 20, 25, 30, 35 and 40 bar. In addition, a 20-h filtration was made at 50 °C and 30 bar. A DDS LabStak M20-filter was used and it was equipped with Desal-5 DK, Desal-5 DL and NF270 membranes. In short-term filtrations, the nanofiltered permeate of the original hydrolyzate had 78–82% xylose of the TDS p (total dry solids in permeate) and the modified hydrolyzate 86–88% xylose of the TDS p . Thus, considerable xylose purification was obtained. The addition of crystalline xylose into the hemicellulose hydrolyzate gave a notable increase in permeate fluxes. The 20-h filtration showed fouling and compaction effects as a flux decrease of approximately 10–25% was detected in the retention integrity test. According to the results, xylose purification from hemicellulose hydrolyzate could be enhanced by nanofiltration.

Complex separation of monosaccharides from each other is commercially carried out by chromatographic methods. The possibility of nanofiltration in a demanding separation of a pentose sugar, xylose, from a hexose sugar, glucose, is studied here. Xylose is an intermediate product in xylitol production and glucose interferes in the process. Feed solutions were made of xylose and glucose in different mass ratios and total monosaccharide concentrations. The mass ratios of xylose to glucose in solutions were 1:9, 1:1 and 9:1 and the monosaccharide concentrations of the solutions were 2, 10 and 30 wt.%. Desal-5 DK, -DL and NF270 membranes were used. Filtrations were done in total reflux mode (i.e. both permeate and retentate were recycled back to the feed tank) at 50 °C and the applied pressures were from 2 to 40 bar. The results indicate that the separation of xylose from glucose by nanofiltration is possible to a limited extent. The mass ratio of xylose to glucose in the permeate was 1.5–3.0 times higher than their ratio in the feed. The observed monosaccharide retentions depend highly on permeate flux, and retentions increase to certain reproducible level as pressure and consequently flux is increased. The observed xylose retentions were from 0 to 80% and the glucose retentions were from 10 to 90%. The effect of total monosaccharide concentration on the observed retention is smaller than the effect of flux. The largest difference between xylose and glucose retentions was detected at permeate fluxes between 5 to 30 kg m −2 h −1 . The ratio of xylose to glucose in the feed had an influence on permeate flux and on xylose retentions. Xylose retentions decreased as the proportion of glucose increased in the feed. The higher the proportion of xylose in the feed the higher was the total permeate flux.

Plant secondary metabolites provide resistance against herbivory if they are capable of decreasing herbivore performance or deterring feeding. Here we test the effects of phlorotannin-containing polar extracts from the brown alga Fucus vesiculosus on the assimilation efficiency and feeding preferences of the herbivorous isopod Idotea baltica . We test the effects separately for each sex of the isopod to test the hypothesis that the digestive efficiencies of the sexes may have diverged. Phlorotannin-containing polar extracts were incorporated into an agar-based artificial food in varying amounts. We also varied the quality of the food, using high-quality food containing animal proteins and low-quality food containing only algal material. The total assimilation efficiency as well as the assimilation efficiencies of carbon and nitrogen decreased with an increasing concentration of phlorotannin-containing extracts. The negative effects on carbon and nitrogen assimilation were higher when extracts were incorporated in the high-quality food. Females were consistently more efficient than males in all assimilation measures; there were no interactions between sex and food quality or phlorotannin concentration, suggesting that the digestive efficiency of the sexes had diverged but that the two sexes responded similarly to phlorotannin enriched artificial food. Although phlorotannin-containing extracts were harmful to performance, they did not deter feeding in preference tests. On the contrary: the isopods preferred the food containing more phlorotannins, suggesting that phlorotannins may act as cues in host recognition. Thus phlorotannins were inefficient deterrents, and I. baltica seems to be adapted to utilizing phlorotannin-containing foods despite their detrimental effects on assimilation. We suggest that F. vesiculosus provides a predation refuge and temporal constancy in availability for I. baltica , both of which select for the ability to utilize it as a food. Phlorotannin-containing polar extracts from F. vesiculosus are still harmful digestibility reducers, and may thereby prevent complete specialization and generate selection for utilization of a wider host range.

Aquatic humic solutes were separated by the non-ionic macroporous XAD-8 and DAX-8 resins and a weakly basic DEAE cellulose anion exchanger from seven different fresh water sources. Synchronous fluorescence spectroscopy was applied for characterization, differentiation and classification of the different humic-solute aggregates. Fluorescence properties verified that humic-solute fractions isolated parallelly with the non-ionic XAD-8 and DAX-8 resins resembled very closely each other speaking strongly for their structural similarities. DAX-8 resin separated ca. 19% more aquatic humic matter than did the analogous XAD-8 resin. It was possible to tentatively differentiate the untreated water samples according to their fluorescent materials. Several distinct classes of chromophores were detected in both DOM and isolated humic fractions by the synchronous technique: λ ex / λ em 280/298, 330/348, 355/373, 400/418, 427/445, 460/478, 492/510 and 516/534 nm.

BACKGROUND: Children with allergic rhinitis are likely to develop asthma.OBJECTIVE: The purpose of this investigation was to determine whether specific immunotherapy can prevent the development of asthma and reduce bronchial hyperresponsiveness in children with seasonal allergic rhinoconjunctivitis.METHODS: From 6 pediatric allergy centers, 205 children aged 6 to 14 years (mean age, 10.7 years) with grass and/or birch pollen allergy but without any other clinically important allergy were randomized either to receive specific immunotherapy for 3 years or to an open control group. All subjects had moderate to severe hay fever symptoms, but at inclusion none reported asthma with need of daily treatment. Symptomatic treatment was limited to loratadine, levocabastine, sodium cromoglycate, and nasal budesonide. Asthma was evaluated clinically and by peak flow. Methacholine bronchial provocation tests were carried out during the season(s) and during the winter.RESULTS: Before the start of immunotherapy, 20% of the children had mild asthma symptoms during the pollen season(s). Among those without asthma, the actively treated children had significantly fewer asthma symptoms after 3 years as evaluated by clinical diagnosis (odds ratio, 2.52; P CONCLUSION: Immunotherapy can reduce the development of asthma in children with seasonal rhinoconjunctivitis.

Aquatic humic solutes were separated in parallel by the non-ionic macroporous DAX-8 and XAD-8 resins from four different fresh water sources. On average, the sorptive power of the DAX-8 resin does not differ systematically from that of the XAD-8 resin. The DAX-8 resin seems to have more precise column characteristics compared with the XAD-8 resin. There was no significant difference between the major elemental compositions of the parallel humic-solute bulks obtained by these two resins. According to the (13)C NMR spectroscopy the content and quality of aliphatic carbons, especially those representing terminal methyl groups or methylene carbons, were the most systematic and powerful discriminating factors between the humic extracts obtained by these two resins. Generally speaking the DAX-8 and XAD-8 resins seem to isolate humic-solute bulks almost equally, although the content of aliphatics is slightly greater for the former, producing mixtures with similar structural compositions for general purposes. The structural composition and quantity of the humic-solute mixture isolable with a weakly basic DEAE-cellulose anion exchange resin differs partially from any humic fraction obtained by non-ionic sorbing solids. The environmental impact was also visible on the quality of the structural fine-chemistry of the different humic isolates obtained both by the DAX-8 and XAD-8 resins.

Evidence of immune system aberrations in patients with epilepsy includes antiphospholipid antibody positivity in adult patients with epilepsy with a prevalence of 19–26% and in 13% of children with partial epilepsy. Also immunoglobulin A deficiency has been reported to exist in up to 25% of epilepsy patients. The possible role of immune mechanisms in the pathogenesis of childhood epilepsy is clinically supported by the effectiveness of immunomodulatory treatments in cases with catastrophic childhood epilepsies. We analyzed a set of various autoantibodies in 50 consecutive children with epilepsy and in 20 healthy control subjects. None of the children had any clinical signs of immune system disorders. The main result was a significantly ( P =0.011) higher prevalence of antiphospholipid antibodies in the study group (44%) compared with controls (10%). These antibodies were unexpectedly common (71–80%) in children with multiple seizure types associated often with symptomatic etiology, early onset and high frequency of seizures. There was no evidence of the antiphospholipid positivity being induced by certain AEDs (e.g. phenytoin or carbamazepine). Even though the significance of these autoantibodies remains unknown, their increased prevalence indicates that immune system mediated mechanisms may have a role in the manifestation of epilepsy in some children.

In this study, we criticize the notion of bradyphrenia and argue that "slowness of thought" in Parkinson"s disease (PD) must be analyzed as slowness of different information-processing stages and that unselected patients should not be used in experimental studies. We selected 32 patients with a long history of PD and 50 control subjects. Sixteen patients had mild cognitive deterioration (not dementia) and 16 patients had preserved cognitive capacities; otherwise the groups were matched. By using computerized tests, we investigated three separate stages: automatic and controlled processing and motor programming. The results indicate that patients with mild cognitive deterioration are slower than patients with preserved cognitive capacities or controls in automatic visual and in controlled processing but not in motor programming. We conclude that the slowing of controlled processing reflects the disruption of central neural networks, that a long history of PD does not necessitate cognitive slowing, and that PD is not a neuropsychologically serviceable category.

The non-cephalic reference electrode (NCRE) of Stephenson and Gibbs (1951) was applied to test the commonly used reference points in evoked potential experiments. Considerable evoked activity to visual stimuli was found in nine out of fourteen subjects at the ear lobe. As a reference the NCRE had definite advantages in these cases since it was free from any stimulus-locked activity. In the auditory and somatosensory modality the NCRE did not show significant advantages over the already established reference points. On the other hand, somatosensory stimulation evoked a short latency potential at the NCRE.