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A magnetic vector hysteresis model is presented using play hysterons as building blocks. The main difference compared to earlier play based magnetic hysteresis models is that instead of forming a superposition of plays with different coercivities, this work uses a set of identical plays which are connected in a chain so that the output of one play acts as input to the next. Like models using a superposition, this yields far more complex minor loop behavior than a single play is capable of. Comparisons are made with measurements on a nonoriented electric steel for BH curves and alternating and rotational losses, showing satisfactory agreement. The approach is found to have both advantages and disadvantages compared to models using superpositions of plays. The problem of determining model parameters becomes simpler and the model can be reversed so either magnetic field or magnetization may be used as known variable. On the other hand, there is no apparent connection to underlying physical processes.

Purpose: the pathophysiologic mechanisms explaining differences in clinical outcomes following COVID-19 are not completely described. This study aims to investigate antibody responses in critically ill patients with COVID-19 in relation to inflammation, organ failure and 30-day survival. Methods: All patients with PCR-verified COVID-19 and gave consent, and who were admitted to a tertiary Intensive care unit (ICU) in Sweden during March–September 2020 were included. Demography, repeated blood samples and measures of organ function were collected. Analyses of anti-SARS-CoV-2 antibodies (IgM, IgA and IgG) in plasma were performed and correlated to patient outcome and biomarkers of inflammation and organ failure. Results: A total of 115 patients (median age 62 years, 77% male) were included prospectively. All patients developed severe respiratory dysfunction, and 59% were treated with invasive ventilation. Thirty-day mortality was 22.6% for all included patients. Patients negative for any anti-SARS-CoV-2 antibody in plasma during ICU admission had higher 30-day mortality compared to patients positive for antibodies. Patients positive for IgM had more ICU-, ventilator-, renal replacement therapy- and vasoactive medication-free days. IgA antibody concentrations correlated negatively with both SAPS3 and maximal SOFA-score and IgM-levels correlated negatively with SAPS3. Patients with antibody levels below the detection limit had higher plasma levels of extracellular histones on day 1 and elevated levels of kidney and cardiac biomarkers, but showed no signs of increased inflammation, complement activation or cytokine release. After adjusting for age, positive IgM and IgG antibodies were still associated with increased 30-day survival, with odds ratio (OR) 7.1 (1.5–34.4) and 4.2 (1.1–15.7), respectively. Conclusion: In patients with severe COVID-19 requiring intensive care, a poor antibody response is associated with organ failure, systemic histone release and increased 30-day mortality.

the pathophysiologic mechanisms explaining differences in clinical outcomes following COVID-19 are not completely described. This study aims to investigate antibody responses in critically ill patients with COVID-19 in relation to inflammation, organ failure and 30-day survival.All patients with PCR-verified COVID-19 and gave consent, and who were admitted to a tertiary Intensive care unit (ICU) in Sweden during March-September 2020 were included. Demography, repeated blood samples and measures of organ function were collected. Analyses of anti-SARS-CoV-2 antibodies (IgM, IgA and IgG) in plasma were performed and correlated to patient outcome and biomarkers of inflammation and organ failure.A total of 115 patients (median age 62 years, 77% male) were included prospectively. All patients developed severe respiratory dysfunction, and 59% were treated with invasive ventilation. Thirty-day mortality was 22.6% for all included patients. Patients negative for any anti-SARS-CoV-2 antibody in plasma during ICU admission had higher 30-day mortality compared to patients positive for antibodies. Patients positive for IgM had more ICU-, ventilator-, renal replacement therapy- and vasoactive medication-free days. IgA antibody concentrations correlated negatively with both SAPS3 and maximal SOFA-score and IgM-levels correlated negatively with SAPS3. Patients with antibody levels below the detection limit had higher plasma levels of extracellular histones on day 1 and elevated levels of kidney and cardiac biomarkers, but showed no signs of increased inflammation, complement activation or cytokine release. After adjusting for age, positive IgM and IgG antibodies were still associated with increased 30-day survival, with odds ratio (OR) 7.1 (1.5-34.4) and 4.2 (1.1-15.7), respectively.In patients with severe COVID-19 requiring intensive care, a poor antibody response is associated with organ failure, systemic histone release and increased 30-day mortality.

According to the WHO, there is an urgent need for better control of viral diseases. Re-positioning existing safe-in-human antiviral agents from one viral disease to another could play a pivotal role in this process. Here, we reviewed all approved, investigational and experimental antiviral agents, which are safe in man, and identified 59 compounds that target at least three viral diseases. We tested 55 of these compounds against eight different RNA and DNA viruses. We found novel activities for dalbavancin against echovirus 1, ezetimibe against human immunodeficiency virus 1 and Zika virus, as well as azacitidine, cyclosporine, minocycline, oritavancin and ritonavir against Rift valley fever virus. Thus, the spectrum of antiviral activities of existing antiviral agents could be expanded towards other viral diseases., Highlights • 339 approved, investigational and experimental safe-in-human antivirals were identified. • 59 compounds, which target ≥3 viral diseases, were selected. • 55 of the 59 compounds were tested against 8 RNA and DNA viruses. • 7 compounds were found to possess novel antiviral activities.

IL-33 represents a potential link between the airway epithelium and induction of a Th2-type inflammatory response in asthma. However, the association with markers of eosinophilic airway inflammation has not previously been reported in patients with steroid-free asthma.To describe the relationship between airway IL-33 and markers of eosinophilic airway inflammation, as well potential triggers of IL-33, in mild, steroid-free asthma.IL-33 mRNA expression and IL-33 immunoreactivity were measured in bronchial biopsies from patients with asthma untreated with inhaled steroids and healthy individuals. Furthermore, fractional exhaled nitric oxide (FeNO) and eosinophils in sputum and BAL were measured, as well as airway hyperresponsiveness to mannitol and methacholine. Epithelial integrity was assessed by computerized image analysis on haematoxylin-stained sections, and TLR mRNA expression by PCR.A total of 23 patients with asthma and 10 healthy individuals were examined (age: 24 years (20-40); females: 53%). The level of IL-33 mRNA expression was significantly higher in patients with asthma compared to healthy individuals (Median (IQR) 1.12 (0.78) vs. 0.86, P = 0.04). There was a positive correlation between IL-33 mRNA expression and the level of FeNO (r = 0.56, P = 0.01), whereas there was no association with airway or blood eosinophils. IL-33 expression was unrelated to loss of epithelial integrity, but correlated with an increased expression of TLR2 and TLR4 (TLR2: r = 0.47, P = 0.04; TLR4: 0.68, P 0.001), as well allergy to house dust mites (HDMs).In mild untreated asthma, the expression of IL-33 mRNA in bronchial mucosa is related to innate immune activation and allergic sensitization to HDM, rather than epithelial damage, and correlates with FeNO. These findings suggest that in mild allergic asthma, IL-33 may represent a link between innate immune activation and FeNO production.

BACKGROUND: Airway hyperresponsiveness (AHR) to inhaled mannitol is associated with indirect markers of mast cell activation and eosinophilic airway inflammation. It is unknown how AHR to mannitol relates to mast cell phenotype, mast cell function and measures of eosinophilic inflammation in airway tissue. We compared the number and phenotype of mast cells, mRNA expression of mast cell associated genes and number of eosinophils in airway tissue of subjects with asthma and healthy controls in relation to AHR to mannitol.METHODS: AHR to inhaled mannitol was measured in 23 non-smoking, corticosteroid-free asthmatic individuals and 10 healthy controls. Mast cells and eosinophils were identified in mucosal biopsies from all participants. Mast cells were divided into phenotypes based on the presence of chymase. mRNA expression of mast cell associated genes was measured by real-time PCR.RESULTS: The proportion of submucosal MCTC was higher in asthmatic individuals with AHR to mannitol compared with asthmatic individuals without AHR (median: 40.3% vs. 18.7%, p=0.03). Increased submucosal MCTC numbers were associated with increased levels of mRNA for TSLP and CPA3 in asthmatics. Reactivity to mannitol correlated significantly with eosinophils in submucosa (r(s): 0.56, p=0.01).CONCLUSION: AHR to inhaled mannitol is associated with an altered submucosal mast cell profile in asthmatic individuals. This mast cell profile is associated with increased levels of TSLP and CPA3. The degree of AHR to mannitol is correlated with the degree of eosinophilic inflammation in the airway submucosa.CAPSULE SUMMARY: Airway hyperresponsiveness to mannitol and methacholine is associated with an increased proportion of chymase-positive mast cells in airway submucosa, which in turn correlated to the expression level of TSLP and CPA3. Finally, airway hyperresponsiveness to mannitol, but not methacholine, is related to submucosal eosinophilic inflammation. This article is protected by copyright. All rights reserved.

Irreversible thermal demagnetization effects can sometimes play a significant role in, for instance, rotating Preisach model (PM) machines. Modeling such phenomena requires field simulation methods such as finite element (FE) analysis in combination with a temperature-dependent vector hysteresis model. This paper explores the feasibility of applying a formalism for temperature-dependent structural hysteresis to magnetics. The net magnetization is expressed as a superposition of contributions from plays. By allowing the anhysteretic curve and the coercivity to depend on temperature, irreversible thermal effects resembling experiments emerge automatically without additional assumptions or adjustable parameters. Incorporating this temperature dependence has negligible impact on the computational efficiency or complexity of the model.

Rationale The alveolar pathology in chronic obstructive pulmonary disease (COPD) involves antigen-driven immune events. However, the induction sites of alveolar adaptive immune responses have remained poorly investigated. Objectives To explore the hypothesis that interfaces between the alveolar lumen and lymphoid aggregates (LAs) provide a structural basis for increased alveolar antigen uptake in COPD lungs. Methods Lung samples from patients with mild (Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage I), moderate–severe (GOLD II–III), and very severe (GOLD IV) COPD were subjected to detailed histological assessments of adaptive immune system components. Never smokers and smokers without COPD served as controls. Results Quantitative histology, involving computerised three-dimensional reconstructions, confirmed a rich occurrence of alveolar-restricted LAs and revealed, for the first time, that the vast majority of vascular or bronchiolar associated LAs had alveolar interfaces but also an intricate network of lymphatic vessels. Uniquely to COPD lungs, the interface epithelium had transformed into a columnar phenotype. Accumulation of langerin (CD207) + dendritic cells occurred in the interface epithelium in patients with COPD but not controls. The antigen-capturing capacity of langerin + dendritic cells was confirmed by increased alveolar protrusions and physical T cell contact. Several of these immune remodelling parameters correlated with lung function parameters. Conclusions Severe stages of COPD are associated with an emergence of remodelled and dendritic cell-rich alveolar–lymphoid interfaces. This novel type of immune remodelling, which predicts an increased capacity to respond to alveolar antigens, is suggested to contribute to aggravated inflammation in COPD.

Background: A unique feature of alveolar mast cells is their low high-affinity IgE receptor (FceRI) expression. Recent discoveries in uncontrolled asthma suggest that the appearance of FceRI-expressing alveolar mast cells may be a novel disease-specific feature of allergic asthma. This study investigates whether increased FceRI-expressing alveolar mast cells are present in patients with mild allergic asthma or even in non-asthmatic allergic rhinitis patients (AR) who have developed bronchial hyperactivity (BHR). Methods: Bronchial and alveolar tissues were obtained from healthy controls, AR patients with or without BHR, and AR patients with concurrent asthma. Samples were processed for immunohistochemical identification of MC(T) and MC(TC) and expression of FceRI and surface-bound IgE. Results: Bronchial mast cell expression of FceRI was high in all groups. In contrast, in the alveolar tissue, the expression of FceRI on mast cells was low in healthy controls and in the AR patient groups, whereas a high expression was present in AR patients with concurrent asthma (P = 0.006 compared to controls). The asthmatics had a 29-fold increase in numbers (P = 0.006) and a 19-fold increase in proportion (P = 0.007) of alveolar mast cells that expressed surface-bound IgE. Conclusions: The present data show that alveolar mast cells in patients with mild atopic asthma, but not atopic patients with AR, have turned into a highly FceRI- and IgE-expressing phenotype. These data support the hypothesis that increased FceRI expression on alveolar mast cells is a novel disease-specific feature of allergic asthma that is important for understanding asthma phenotypes and designing new therapeutic strategies. (Less)

The efficiency of a biologically activated carbon system for treating wastewater polluted with petroleum products was examined and the effects of process parameters on its efficacy were evaluated. In each experiment 17 alkylated and 19 non-alkylated polycyclic aromatic hydrocarbons (PAHs) and total petroleum hydrocarbons (TPHs, C(10)-C(40)) were extracted using semipermeable membrane devices from wastewater before and after treatment. The acquired data during experiments were analyzed using principal component analysis (PCA). The treatment system robustly removed dissolved PAHs across the studied ranges of the process parameters, providing overall removal efficiencies of 96.9-99.7% for the sum of 36 PAHs. However, the major contributor to their removal was sorption rather than biodegradation, and despite the general efficiency of the process there was up to a 9-fold range in the sums of quantified PAHs in the effluents between experiments. Combinations of long process contact time (24 h) with high temperature (24 degrees C) and moderate oxygen concentration (6-7 mg O(2) L(-1)) resulted in good removal of bioavailable PAHs. The removal of TPHs was more dependent on biological activities during the wastewater treatment, and consequently more dependent on the process parameters. In addition, small but significant proportions of PAHs were volatilized and released during the wastewater treatment.

A chemical and ecotoxicological assessment of treatment of wastewater that had been polluted with petroleum products using only Activated Sludge (AS) and four biologically activated sorbents (BASs), consisting of activated sludge plus: coal-based activated carbon (-C1), coconut shell-based activated carbon (-C2), zeolite (-Z), and anthracite (-A) were conducted. The efficiency and robustness of the four wastewater treatment systems were evaluated by calculating the reduced total petroleum hydrocarbon (TPH) and polycyclic aromatic hydrocarbon (PAH) contents and the acute ecotoxicity of the effluents. The chemical analysis showed that the combined treatment systems were very effective for reducing the total petroleum hydrocarbon and readily bioavailable PAH contents. The most efficient systems were the BAS-C1 and -C2, which removed 60–88% and 99.5–99.6% of TPH and PAH, respectively. The activated sludge-only treatment was the least effective for purifying the wastewater. Chemical oxygen demand was reduced by >90% by all carbon-based BASs (BAS-C1, BAS-C2 and BAS-A). Shifts in the relative composition of the individual PAHs were identified in samples taken before and after treatment. Algal and bacterial bioassays showed that the toxicities of effluents following treatment by all four systems (except AS for algae) were reduced by more than 80% and 90%, respectively. However, crustacean tests indicated that the carbon-based BASs reduced the toxicity [Vtox(50)] only by 19–67%. Our results indicated that the combination of sorption and biodegradation processes have great potential in the treatment of petroleum products polluted wastewater and is less sensitive for inhibitors of the biological process than treatments in which activated sludge alone is used. The assessment of chemical and ecotoxicological endpoints provided valuable information, but contrasting results for one of the assays indicates that further analysis on the capacity of the different treatment systems is warranted.

Semipermeable membrane devices (SPMDs) were exposed at ten sampling points, each representing a different stage in the treatment process, in a municipal sewage treatment plant. Differences in SPMD uptake kinetics of polycyclic aromatic hydrocarbons (PAHs) due to variations in conditions at the sampling sites were evaluated by using five performance reference compounds (PRCs) with log K(ow) values of 4.20 to 6.34. PRC release rate constants (k(e,PRC) values) were calculated for PRCs for which 50-98% of the initial amounts were lost during the sampling period. The k(e,PRC) values were high, ranging from 0.08 to 0.11 day(-1) for the studied PRCs, at sampling site W1 (raw sewage), the only sampling site where significant amounts of the PRCs with log K(ow) values5 were released from the SPMDs. At the other sampling sites, only PRCs with log K(ow) values between 4.20 and 4.50 were released in significant amounts. The release rates at these sites were lowest (0.04 day(-1)) at sampling site W9 (the secondary clarifier) and highest (0.18 day(-1)) at W8 (the active sludge aeration basin). Differences between sampling rates (R(s)) obtained using published laboratory-calibrated data and PRC-corrected R(s) values were visualized by principal component analysis (PCA). The water concentrations of 24 studied PAHs fell substantially during the course of the sewage treatment process. However, low molecular weight PAHs were more effectively removed than high molecular weight PAHs. Significant deviations between actual and estimated water concentrations may arise unless PRC-corrected R(s) values are applied.

Recent survey results for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins) in Baltic Sea sediments from Finland, Sweden and Denmark were merged with previously published Baltic Sea data. Regional distribution of concentration levels, differences in congener patterns, and temporal changes in sediment profiles were examined. One of the main objectives was to study if any major point sources for different PCDD/F congeners could be identified on a regional scale, based on sediment records. The survey confirmed the impact of chlorophenol production derived highly chlorinated PCDF-congeners on the total toxicity in sediments in the Gulf of Finland near the Kymijoki river estuary. Signatures of other point sources or combined point sources pertinent to specific industry branches or particular production processes (such as pulp bleaching, vinyl chloride production, thermal processes) may be discerned. However, the findings did not support any of the known point sources significantly influencing those congeners that are most abundant in Baltic herring and salmon. Instead, regional distributions in the Baltic Sea indicate that atmospheric deposition may act as a major source for those congeners and especially for 2,3,4,7,8-PeCDF. There were clear indications of declines in levels in sediment in some areas, but generally the levels of highly chlorinated PCDD/Fs on the northern coast of the Gulf of Finland were still high when compared with other areas of the Baltic Sea. Major areas with data gaps cover the south-eastern and eastern coastal regions of the Baltic Proper and the southern Gulf of Finland.

Semipermeable membrane devices (SPMDs) are previous termanext term widely used passive sampling methodology for both waterborne and airborne hydrophobic organic contaminants. The exchange kinetics ...

Field concentrations of polychlorinated biphenyls (PCBs) were measured in sediment and nine marine soft bottom invertebrate species. Lipid- and organic carbon normalised biota-sediment accumulation factors (BSAFs) were determined for 29 nonplanar and 11 coplanar congeners. To investigate whether the bioaccumulation was in thermodynamic equilibrium with the sediment, the determined BSAFs were compared to theoretically calculated ones to obtain a BSAFdet./BSAFtheor-ratio. Large interspecific variations were found: one suspension feeding and one deposit feeding species of brittle stars (Amphiura filiformis and A. chiajei), and one predatory polychaete (Glycera rouxii) had ratios>1 for congeners with logKow>6.5. In these species there was also a linear relationship between logKow and BSAF, both for coplanar and for planar congeners but with lower values for coplanar ones. For other species the pattern was more scattered. Only the deposit feeding polychaete Melinna cristata had BSAFdet./BSAFtheor-ratios

Semipermeable membrane devices (SPMD) represent a passive sampling technology that is becoming widely used for monitoring of surface waters pollution. While "classic" procedures employ dialysis to recover target compounds from exposed SPMDs, in the present study analytes were isolated from cut membrane together with sequestering medium (triolein) using hexane as an extraction solvent. This approach allowed us to reduce the time needed for accomplishment of isolation step from 48 h to only 1 h. Automated gel permeation chromatography (GPC) clean-up is employed in the following step to separate triolein from analytes fraction. Musk compounds (MCs), polychlorinated biphenyls (PCBs), brominated flame retardants (BFRs) and several other persistent organochlorine compounds (OCs) were determined in the respective fraction by GC method employing selective detectors (MSD, ECD). As shown in a series of analyses of SPMDs deployed in various aquatic ecosystems, high recoveries and good repeatability of results together with a possibility to obtain the information on the pollution of sampling site at the day of sample arrival to laboratory make this newly implemented procedure an interesting alternative to time consuming dialysis.

The gas phase polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs in the atmosphere of five European countries (Austria, the Czech Republic, Poland, Slovakia and Sweden) were measured simultaneo ...

Alterations of cytokine responses are thought to favor the establishment of persistent hepatitis C virus (HCV) infections, enhancing the risk of liver cirrhosis and hepatocellular carcinoma. Here we demonstrate that the expression of the HCV core (C) protein in stably transfected T cells correlates with a selective reduction of interleukin-2 (IL-2) promoter activity and IL-2 production in response to T-cell receptor triggering, whereas the activation of IL-4, IL-10, gamma interferon, and tumor necrosis factor alpha was moderately increased. This altered cytokine expression profile was associated with a perturbation of mitogen-activated protein (MAP) kinase responses. Extracellular regulated kinase and p38 were constitutively phosphorylated in C-expressing cells, while triggering of the costimulatory c-Jun N-terminal kinase (JNK) signaling cascade and activation of the CD28 response element within the IL-2 promoter appeared to be impaired. The perturbations of MAP kinase phosphorylation could be eliminated by cyclosporine A-mediated inhibition of nuclear factor of activated T cells, suggesting that the inactivation of JNK signaling and hyporesponsiveness to IL-2 induction were downstream consequences of C-induced Ca2+flux in a manner that mimics the induction of clonal anergy.

The bactericide triclosan and methyl triclosan, an environmental transformation product thereof, were detected in lakes and in a river in Switzerland at concentrations of up to 74 and 2 ng L(-1), respectively. Both compounds were emitted via wastewater treatment plants (WWTPs), with methyl triclosan probably being formed by biological methylation. A regional mass balance for a lake (Greifensee) indicated significant removal of triclosan by processes other than flushing. Laboratory experiments showed that triclosan in the dissociated form was rapidly decomposed in lake water when exposed to sunlight (half-life less than 1 h in August at 47 degrees latitude). Methyl triclosan and nondissociated triclosan, however, were relatively stable toward photodegradation. Modeling these experimental data for the situation of lake Greifensee indicated that photodegradation can account for the elimination of triclosan from the lake and suggested a seasonal dependence of the concentrations (lower in summer, higher in winter), consistent with observed concentrations. Although emissions of methyl triclosan from WWTPs were only approximately 2% relative to those of triclosan, its predicted concentration relative to triclosan in the epilimnion of the lake increases to 30% in summer. Passive sampling with semipermeable membrane devices (SPMDs) indicated the presence of methyl triclosan in lakes with inputs from anthropogenic sources but not in a remote mountain lake. Surprisingly, no parent triclosan was observed in the SPMDs from these lakes. Methyl triclosan appears to be preferentially accumulated in SPMDs under the conditions in these lakes, leading to concentrations comparable to those of persistent chlorinated organic pollutants.

Background Asthmatic patients have higher microbiome diversity and an altered composition, with more Proteobacteria and less Bacteroidetes compared with healthy control subjects. Studies comparing airway inflammation and the airway microbiome are sparse, especially in subjects not receiving anti-inflammatory treatment. Objective We sought to describe the relationship between the airway microbiome and patterns of airway inflammation in steroid-free patients with asthma and healthy control subjects. Methods Bronchoalveolar lavage fluid was collected from 23 steroid-free nonsmoking patients with asthma and 10 healthy control subjects. Bacterial DNA was extracted from and subjected to Illumina MiSeq sequencing of the 16S rDNA V4 region. Eosinophils and neutrophils in the submucosa were quantified by means of immunohistochemical identification and computerized image analysis. Induced sputum was obtained, and airway hyperresponsiveness to mannitol and fraction of exhaled nitric oxide values were measured. Relationships between airway microbial diversity and composition and inflammatory profiles were analyzed. Results In asthmatic patients airway microbial composition was associated with airway eosinophilia and AHR to mannitol but not airway neutrophilia. The overall composition of the airway microbiome of asthmatic patients with the lowest levels of eosinophils but not asthmatic patients with the highest levels of eosinophils deviated significantly from that of healthy subjects. Asthmatic patients with the lowest levels of eosinophils had an altered bacterial abundance profile, with more Neisseria , Bacteroides , and Rothia species and less Sphingomonas , Halomonas , and Aeribacillus species compared with asthmatic patients with more eosinophils and healthy control subjects. Conclusion The level of eosinophilic airway inflammation correlates with variations in the microbiome across asthmatic patients, whereas neutrophilic airway inflammation does not. This warrants further investigation on molecular pathways involved in both patients with eosinophilic and those with noneosinophilic asthma.

Surface sediment, amphipods (Monoporeia affinis), isopods (Saduria entomon) and fourhorn sculpins (Oncocottus quadricornis) were collected at two coastal stations in the Gulf of Bothnia, one in the Bothnian Bay and the other in the Bothnian Sea. The objective was to study the concentrations, composition profiles, bioaccumulation features and spatial differences of organochlorine compounds such as hexachlorocyclohexanes (HCHs), DDTs, hexachlorobenzene (HCBz), chlordanes (CHLs), dieldrin, Mirex and polychlorinated biphenyls (PCBs). All groups of compounds were found in every sample investigated, with the exception of Mirex that was not detected in the sediment samples. The concentrations for e.g. PCBs and CHLs ranged from 700 to 2400 and 70 to 400 ng/g lipid in the specimens. For the corresponding sediments the results were 9.0-9.3 ng/g dw for PCBs and 0.54-0.57 ng/g dw for CHLs, respectively. Bioaccumulation differences between the species with regard to both degree of and type of compound were observed. The highest accumulation potential was found for the cyclodiene compounds including CHLs and Mirex in isopod. Finally, there were only small concentration and bioaccumulation differences between the two stations.

The purpose of the study was to evaluate the hepatic 7-ethoxyresorufin O -deethylase (ERO D)-induction and whole fry immunohistochemical staining of cytochrome P4501A1 in two different salmonid species exposed by microinjection to the lipid soluble components extracted from feral Baltic salmon ( Salmo salar ) roe predicted to develop the larval mortality syndrome M74. In both salmon and brown trout ( Salmo trutta ), a dose-dependent induction of the hepatic EROD-activity was recorded. No dose-dependent induction was seen in groups exposed to different concentrations of the lipophilic substances extracted from farmed roe. The immunohistochemical study revealed an exposure-dependent induction of cytochrome P4501A1 in the liver and in endothelial tissue in both salmon and brown trout.

Blue mussel, flounder, perch and lamprey from the Gulf of Gdansk accumulate many tetra- through hepta-CNs. Highest concentrations in fishes and lamprey are PCN congeners such as nos. 42, 52, 60, 61 and 69, which do not have vicinal (adjacent) carbon atoms unsubstituted with chlorine (NVC-Cl PCNs) and seem to be relatively resistant in the marine environment. In mussel, chloronaphthalenes such as nos. 3840, 33/34/37, 2843 and 47 dominate, i.e. the congeners, which have two or three vicinal carbon atoms unsubstituted with chlorine (DVC-Cl and TVC-Cl PCNs). PCNs with two vicinal carbon atoms unsubstituted with chlorine (DVC-Cl PCNs) are less abundant in fish and lamprey than NVC-Cl members, while those congeners with three (TVC-Cl PCNs) or four (QVC-Cl PCNs) vicinal carbon atoms unsubstituted are present as only minor compounds or are absent. Congener-specific data obtained using a non-destructive sample extraction and clean-up method coupled to HRGC-HRMS can be useful to explain potential species- or site-specific differences of the pollution pattern with PCNs. Most of the hexa-CNs, both hepta-CNs and some penta- and tetra-CNs show their high potency for bioaccumulation in flounder when related to mussel as their food.

To identify potential sources and accumulation features concentrations, profiles, and patterns of polychlorinated naphthalene (PCN) residues were determined in sediment, mussel, crab, plankton, and...

Three-spined sticklebacks were exposed to 20 polychlorinated biphenyls (PCBs) through gastrointestinal intake. The PCBs, viz. 2,2{prime},3,4-TeCB, 2,2{prime},4,6{prime}-TeCB, 2,3,3{prime},5{prime}-TeCB, 2,3,4,4{prime}-TeCB, 2,3{prime},4,5{prime}-TeCB, 3,3{prime},4,5-TeCB, 2,2{prime},3,4{prime},6-PeCB, 2,2{prime},4,4{prime},5-PeCB, 2,2{prime},4,6,6{prime}-PeCB, 2,3,3{prime},5,6-PeCB, 2,3,4,4{prime},6-PeCB, 3,3{prime}4,4{prime}5-PeCB, 2,2{prime},3,4,5,6{prime}-HxCB, 2,2{prime},4,4{prime},5,5{prime}-HxCB, 3,3{prime},4,4{prime},5,5{prime}-HxCB, 2,2{prime},3,3{prime},4,5,6-HpCB, 2,2{prime},3,4,4{prime},6,6{prime}-HpCB, 2,2{prime},3,4{prime},5,6,6{prime}-HpCB, 2,3,3{prime},4,4{prime},5,6-HpCB, and 2,3,3{prime},4{prime},5,5{prime},6-HpCB, were selected by means of a full factorial design in combination with principal component analyses based on several physicochemical properties of tetra- through hepta-PCBs. After exposure to the training set, pooled samples of the sticklebacks were analyzed by GC-MS after lipid determination and cleanup using Florisil open-column chromatography. Bioaccumulation factors (BAFs) were calculated on a lipid basis by dividing the PCB concentrations in the fish by the respective concentrations in the feed. Higher chlorinated PCBs showed, in general, higher bioaccumulation than the lower chlorinated congeners. Polychlorinated biphenyls with vicinal hydrogens in the meta- and para-positions exhibited low bioaccumulation. Finally, 18 of the 20 measured BAFs were used to calculate a multivariate quantitative structure-activity relationship (QSAR) by means of partial least squares fitting to latent structures. By applying this QSAR, the bioaccumulation potentials of 136 nontested tetra- through hepta-PCB congeners were predicted.

Levels of PCBs in the aquatic environment of the Gulf of Bothnia: Benthic species and sediments

In 1974, abnormally high mortality was recorded among yolk-sac fry of Baltic salmon (Salmo salar) originating from feral females manually stripped and fertilized with milt from feral males. The cause of this mortality, designated M74, is unknown. The hypothesis is that xenobiotic compounds responsible for reproduction failure in higher vertebrates in the Baltic Sea also interfere with reproduction in Baltic salmon. The significance of M74 should not be underestimated, because the syndrome has caused up to 75% yearly mortality of developing Baltic salmon yolk-sac larvae in a fish hatchery dedicated to production of smolt during the last two decades. The author cannot exclude the possibility that only a relatively low number of naturally spawned eggs develop normally because of M74. No individual pollutant has been shown to be responsible for the development of M74 syndrome. However, a higher total body burden of organochlorine substances may be responsible for the M74 syndrome. The presence of induced hepatic cytochrome P450 enzymes in both yolk-sac fry suffering from M74 and adult feral females producing offspring affected by M74 supports this hypothesis. In addition, the P450 enzyme activity in offspring from feral fish is higher than the activity in yolk-sac fry from hatchery-raised fish,more » suggesting that feral Baltic salmon are influenced by organic xenobiotics.« less

Samples of striped bass, crabs and lobsters were collected in Newark Bay and the New York Bight. The fish muscle and the hepatopancreas and meat from the crabs were subjected to congener specific analysis. All samples were found to be contaminated by 2,3,7,8-tetraCDD and a series of other highly hazardous 2,3,7,8-substituted congeners as well as less hazardous PCDDs and PCDFs. A value exceeding 6000 ppt wet tissue weight of 2,3,7,8-tetraCDD was found in a sample of crab hepatopancreas, which seems to be the highest value so far reported in a food product. The crab meat, on the other hand, contained only 100 ppt. In general the crustaceans contained many congeners, while the fish samples contained only 2,3,7,8-substituted compounds. An unknown compound, possibly a tetrachlorodibenzothiophene, was the dominating peak in most of the crustacean samples.

Statistical mechanics is employed to derive magnetic and magnetostrictive bulk properties of soft magnetic materials dominated by domain wall motion. The material is divided into an ensemble of volumes with uniform magnetization, each one much smaller than a typical domain but much larger than one atom. The energy for such a volume element is assumed to consist of an internal energy: the interaction with the external magnetic field and a mean field interaction with the surrounding medium. The volume fractions of discrete mesoscopic magnetizations in the medium are derived from Boltzmann statistics. The bulk magnetization is the weighted average of the mesoscopic values. Magnetostriction is treated in a similar way. Calculations are compared with two-dimensional measurements on grain-oriented silicon–iron.

Semipermeable membrane devices (SPMDs) are passive samplers used to measure the vapor phase of organic pollutants in air. This study tested whether extremely high wind-speeds during a 21-day sampling increased the sampling rates of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), and whether the release of performance reference compounds (PRCs) was related to the uptakes at different wind-speeds. Five samplers were deployed in an indoor, unheated, and dark wind tunnel with different wind-speeds at each site (6-50 m s(-1)). In addition, one sampler was deployed outside the wind tunnel and one outside the building. To test whether a sampler, designed to reduce the wind-speeds, decreased the uptake and release rates, each sampler in the wind tunnel included two SPMDs positioned inside a protective device and one unprotected SPMD outside the device. The highest amounts of PAHs and PCBs were found in the SPMDs exposed to the assumed highest wind-speeds. Thus, the SPMD sampling rates increased with increasing wind-speeds, indicating that the uptake was largely controlled by the boundary layer at the membrane-air interface. The coefficient of variance (introduced by the 21-day sampling and the chemical analysis) for the air concentrations of three PAHs and three PCBs, calculated using the PRC data, was 28-46%. Thus, the PRCs had a high ability to predict site effects of wind and assess the actual sampling situation. Comparison between protected and unprotected SPMDs showed that the sampler design reduced the wind-speed inside the devices and thereby the uptake and release rates.

Although the hepatitis C virus (HCV) genome is synthesized by the virus-encoded RNA-dependent RNA polymerase NS5B, other viral and cellular factors are assumed to be required for template-specific initiation and regulation of RNA-synthesis. The cellular protein La, which normally associates with RNA polymerase III transcripts, also interacts with the 5'- and 3'-untranslated regions of several RNA viruses, including HCV. To investigate whether other viral gene products may be involved in this interaction, we constructed an HCV cDNA expression library in bacteriophage T7 allowing portions of the HCV polyprotein to be displayed on the phage surface. Screening of the phage library against La resulted in selection of clones displaying the N-terminal region of HCV NS5A. Co-precipitation of full-length and truncated forms of recombinant NS5A with La revealed that the N-terminal region of NS5A was both necessary and sufficient for binding to La. Although this region of NS5A is essential for HCV replication, the role of the NS5A-La interaction in the infected cell remains to be established.

Semipermeable membrane devices (SPMDs) were deployed at six sites in the Bangkok region, Thailand, to investigate spatial variations in atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs). Sampling sites affected by various levels of traffic intensity were studied. In addition, PAH levels were determined in a common human food plant (water spinach) harvested from canals and ponds in the sampling areas. Significant differences in atmospheric PAH concentrations between sites were found, with 10 times higher PAH levels in the urban areas compared to the rural areas. Increasing concentrations of 1-methylphenanthrene relative to phenanthrene were found in the urban air close to the city center, indicating that traffic probably contributed to the higher PAH concentrations detected. Due to SPMD's passive sampling technique, their long-term operation and high ability to detect spatial differences, they proved to be suitable for semiquantitative field studies of PAHs. The PAH compounds sampled with SPMDs were mainly associated with gaseous PAHs, while both gas phase and particle-bound PAHs were detected in the plant samples. The relative abundance ratios of some PAHs in the plants were not well correlated with the ratios detected in the SPMDs, indicating that gas-phase exposure made low contribution to the PAH concentrations in the plants. However, similarities in the profiles of 3-ring PAHs between the SPMD and plant samples indicate that gas-phase exchange occurs between the atmosphere and the plants.

To obtain accurate design tools for applications involving giant magnetostrictive materials, magnetomechanical hysteresis effects should be taken into account. The problem consists of determining the magnetization and mechanical strain from the combined past history of magnetic field and mechanical stress. In this work, coupled magnetomechanical hysteresis has been modeled by using simple path‐dependent differentials to accumulate the past history in functions related to the magnetization and strain through material‐dependent parameters. By using anhysteretic curves and a few additional parameters to characterize a material, major, and minor loops with respect to both field and stress have been calculated for Terfenol‐D and have shown good agreement with experiments.

A phenomenological inherently vector hysteresis model employing simple differentials as a means of keeping track of the past history of the magnetic field is proposed. This results in a simple and computationally fairly efficient formulation for vector hysteresis of any dimension. An expression for determining model parameters from experimental data or from the Preisach function is given. The model exhibits rotational hysteresis and reduction of remanent magnetization by an orthogonal field and reduces to the classical Preisach model in one dimension. Details concerning the numerical implementation are discussed and computational examples demonstrating model properties are presented.

Magnetic hysteresis effects have been included in a finite‐element description of a magnetic circuit by using the classical vector Preisach model for the constitutive relation between H and B. The influence of an external electric circuit is taken into account by adding equations derived from Faraday’s law. Computational results are presented for a magnetic circuit used in a magnetostrictive device.

A voltage #x2010;fed magnetostrictive drive element is modeled. The model involves the Terfenol rod, a magnetizing coil, permanent magnets, a magnetic circuit, and predicts displacements and stress ...