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The glycolipid-anchored glycoprotein CD59 inhibits assembly of the lytic membrane attack complex of complement by incorporation into the forming complex. Absence of CD59 and other glycolipid-anchored molecules on circulating cells in the human hemolytic disorder paroxysmal nocturnal hemoglobinuria is associated with intravascular hemolysis and thrombosis. To examine the role of CD59 in protecting host tissues in health and disease, CD59-deficient (CD59−/−) mice were produced by gene targeting in embryonic stem cells. Absence of CD59 was confirmed by staining cells and tissues with specific antibody. Despite the complete absence of CD59, mice were healthy and fertile. Erythrocytes in vitro displayed increased susceptibility to complement and were positive in an acidified serum lysis test. Despite this, CD59−/− mice were not anemic but had elevated reticulocyte counts, indicating accelerated erythrocyte turnover. Fresh plasma and urine from CD59−/− mice contained increased amounts of hemoglobin when compared with littermate controls, providing further evidence for spontaneous intravascular hemolysis. Intravascular hemolysis was increased following administration of cobra venom factor to trigger complement activation. CD59−/− mice will provide a tool for characterizing the importance of CD59 in protection of self tissues from membrane attack complex damage in health and during diseases in which complement is activated.

The bactericidal effect of high levels of negative ions was studied using a custom-built electrostatic space charge device. To investigate whether the ion-enriched air exerted a bactericidal effect, an aerosol containing Salmonella Enteritidis (SE) was pumped into a sealed plastic chamber. Plates of XLT4 agar were attached to the walls, top, and bottom of the chamber and exposed to the aerosol for 3 h with and without the ionizer treatment. The plates were then removed from the chamber, incubated at 37 degrees C for 24 h, and colonies were counted. An average of greater than 10(3) CFU/plate were observed on plates exposed to the aerosol without the ionizer treatment (control) compared with an average of less than 53 CFU/plate on the ionizer-treated plates. In another series of experiments, the SE aerosol was pumped for 3 h into an empty chamber containing only the ionizer and allowed to collect on the internal surfaces. The inside surfaces of the chamber were then rinsed with 100 ml phosphate-buffered saline that was then plated onto XLT4 plates. While the rinse from the control chamber contained colony counts greater than 400 CFU/ml of wash, no colonies were found in the rinse from the ionizer-treatment chamber. These results indicate that high levels of negative air ions can have a significant impact on the airborne microbial load, and that most of this effect is through direct killing of the organisms. This technology, which also causes significant reduction in airborne dust, has already been successfully applied for poultry hatching cabinets and caged layer rooms. Other potential applications include any enclosed space such as food processing areas, medical institutions, the workplace, and the home, where reduction of airborne and surface pathogens is desired.

In north Queensland, 14 localities were surveyed for mosquito larvae (third and fourth instar) during summer/autumn and winter from 1996 to 1999. Absolute population numbers in subterranean habitats, mainly service manholes and pits (97%) but also some wells, septic tanks, storm drains, and sumps, were expressed as a proportion of total numbers in these sites plus surface sites within a 100-m radius. When correction factors were applied to subterranean samples, the 472,477 larvae mainly of Aedes tremulus (Theobald) group, Aedes notoscriptus (Skuse), and Aedes aegypti (L.) comprised 78% of the total population. In relation to the proportion of the overall immature mosquito population from subterranean habitats (propsub), linear regression coefficients for minimum temperature, relative humidity, and Mesocyclops copepod prevalence were significant for winter data; but for summer, only relative humidity was significant. Linear regression coefficients for Mesocyclops prevalence approached significance (P = 0.061) in summer. When multiple linear regression was used to model propsub, 68% of the variation was accounted for by relative humidity and the prevalence of Mesocyclops. In the drier and cooler towns, increased use of subterranean sites during winter was caused by reduced availability of surface oviposition sites because of the dry season. In the wetter coastal towns, no such restrictions applied and ambient conditions remained more equitable all year round. Mesocyclops were surprisingly common, particularly in these coastal towns. Release of known numbers of Mesocyclops indicated that 3-sweep netting in service manholes was sensitive down to densities of one Mesocyclops per 10 liters, and overall recovery varied from 1 to 4%. In relation to control, service manholes represent a stable habitat for mosquito (7% positive overall) and Mesocyclops populations. If they remained wet, service manholes positive for mosquito immatures or Mesocyclops during summer/autumn had 96% and 85% chance, respectively, of being positive the following winter. Even allowing for the effect of drying, a mosquito-positive manhole had a 79% chance of remaining positive the following winter. In view of the importance of these sites as refuges from adverse ambient conditions, it is proposed that a winter control strategy using Mesocyclops presents a cost-effective control option to reduce the recolonization of surface sites when conditions become more suitable.

Dust has been shown to be an important mechanism for airborne transmission of disease-causing agents. Although there are a variety of treatments that can reduce airborne dust, most of them are not practical in areas such as caged layer rooms where dust levels can be relatively high. In this study, an electrostatic space charge system was shown to be very effective on both artificial and naturally generated dust in a caged layer room. Duplicated trials of the system showed a reduction in average concentration of artificially generated dust ranging from 72 to 91% by ionizer treatment - depending on the initial concentration. The treatment reduced concentration of naturally generated dust from mature White Leghorn chickens in cages by an average of 52%. These results show that use of an electrostatic space charge system can significantly reduce dust in caged layer areas, resulting in a lower potential for respiratory problems of workers as well as chickens in these areas.

Serological surveillance can be an important component for egg quality assurance programs geared toward controlling problems with Salmonella enterica serovar Enteritidis (S. enteritidis) within a flock. Serum is the primary sample source for the procedures, although egg yolk antibody assays have become popularity in recent years. However, these assays tend to be labor intensive, requiring procedures for extracting antibodies from the yolk followed by assaying the samples. We describe an adaptation of the agar gel precipitin (AGP) test for use in detecting antibodies to S. enteritidis deposited in egg yolks of infected hens. Yolk or sera from infected birds were administered to wells cut into seven-well clusters in an agar gel plate, and detection antigen was added to the center well. The agar gels were incubated for 24 h and then examined for the presence of precipitin lines formed by the interaction of antibody with antigen. Three different antigens were tested: S. enteritidis flagella, SEF14 (a 14-kDa fimbrial protein produced ostensibly by S. enteritidis), and a sodium deoxycholate extract of whole S. enteritidis organism. Flagella and the organism extract detected antibodies to S. enteritidis in the yolk and sera, whereas SEF14 was not reactive. Positive reactions were observed in serum 1 wk postchallenge, whereas in yolks, this was further delayed by 1 wk. The sensitivity of the test was slightly less than the standard microagglutination assay, although specificity was slightly higher, as indicated by results from sera and yolks from birds infected with Salmonella enterica serovar Typhimurium. Simplicity and low labor requirements of the assay would allow for the potential testing of several hundred egg samples within a day, which would make up for test shortcomings due to sensitivity. The AGP test could be an important tool for individuals using serological testing to monitor the S. enteritidis situation within their flocks or as a rapid screen for vaccine responses. The assay could also be used in tandem with other AGP tests to screen for the presence of multiple avian pathogens.

We present X-ray emission line equivalent width images of the bright Galactic supernova remnant Cassiopeia A for the elements Si, S, Ar, Ca, and Fe using a 50,000 s observation with the Advanced CCD Imaging Spectrometer on the Chandra X-ray Observatory. The images essentially identify the bulk of detectable ejecta of these elements over a wide range of surface brightness, and show morphologies distinctly different from that of the broadband X-ray emission and of the 4-6 keV continuum emission. The Si, S, Ar, and Ca maps, while different in turn from those of Fe, show that these X-ray emitting ejecta are distributed similarly to the fast optical ejecta knots, and clearly delineate the X-ray counterpart of the northeast optical jet. Low surface brightness regions just outside the bright shell in the north and west are also shown to have strong line emission. The strong Fe emission is exterior to that of other elements in the east, as previously noted, but is generally coincident elsewhere. The projected interior has relatively little emission traced by high line equivalent widths.

The ability to repair promutagenic damage resulting from exposure to carcinogens is a critical factor in determining quantitative relationships in carcinogenesis, including the target cell for neoplasia. One major pathway for the repair of alkylating agent-induced DNA damage involves removal of alkylated bases by N -methylpurine-DNA-glycosylase (MPG), the first enzyme in base excision repair. We have measured the expression level of MPG mRNA in liver, lung, and kidney of Sprague–Dawley rats as a function of age. A quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) method was used to measure cellular MPG mRNA. MPG mRNA was readily detectable in each tissue analyzed and the age-dependent and tissue specific expressions were not statistically different. The lowest amount of mRNA was measured in preweanling liver and the highest amounts were found in preweanling lung and kidney. Since MPG is reported to be responsible for excision of 1, N 6 -ethenoadenine and N 2 ,3-ethenoguanine, two promutagenic DNA adducts of vinyl chloride (VC) and vinyl fluoride (VF), we examined the regulation of this enzyme after carcinogen exposure. Expression of MPG was induced in rat liver by these carcinogens. In order to determine the repair capacity in different cell populations of liver, we measured MPG gene expression in isolated hepatocytes and nonparenchymal cells (NPC). The amount of MPG mRNA was 4.5–5 times higher in hepatocytes than in NPC of control rats. Induction of MPG expression was observed in hepatocytes of VF exposed-rats but not in NPC. The expression of MPG in NPC was only 15% of that of the hepatocytes from exposed rats. Western blots of MPG protein confirmed the cell type differences, but did not show increased protein in exposed vs. control liver and hepatocytes. Since metabolism of VC and VF requires CYP2E1, an enzyme exhibiting much greater activity in hepatocytes, formation of etheno adducts preferentially occurs in hepatocytes. These data suggest that cellular differences in the repair of N -alkylpurines may be a critical mechanism in the development of cell specificity in VC carcinogenesis.

The concentrations of boron in the Aire and Calder which have been measured in order to validate the GREAT-ER model have been used to derive a predicted environmental concentration (PEC) for boron in the Aire catchment in Yorkshire. The data have been obtained from 33 sites, with monthly sampling over a 2-year period. The 90th percentile of the means of measured concentrations (242 microg l(-1)) is higher than the 90th percentile predicted by the GREAT-ER model (186 microg l(-1)), if river stretches are normalised by their flow volumes, and unpolluted headwaters are included in the catchment averaging procedure. However, if the river stretches are normalised by the length of the respective stretch, and unpolluted headwaters are included, a lower regional PEC of 28 microg l(-1) is obtained. If normalisation by stretch length is appropriate for regional risk assessment, then the 90th percentile of the means of the measured data will overpredict the regional boron concentration in a catchment such as the Aire, with a low natural level of boron in the headwaters. Monitoring data for boron in the effluents from sewage treatment works in the Aire catchment, and for boron in the Went and Rother catchments, with a higher background boron level, are also given.

Experiments were conducted to test several methods for estimating low temperature thresholds for seed germination. Temperature responses of nine weeds common in annual agroecosystems were assessed in temperature gradient experiments. Species included summer annuals (Amaranthus albus, A. palmeri, Digitaria sanguinalis, Echinochloa crus-galli, Portulaca oleracea, and Setaria glauca), winter annuals (Hirschfeldia incana and Sonchus oleraceus), and Conyza canadensis, which is classified as a summer or winter annual. The temperature below which development ceases (Tbase) was estimated as the x-intercept of four conventional germination rate indices regressed on temperature, by repeated probit analysis, and by a mathematical approach. An overall Tbase estimate for each species was the average across indices weighted by the reciprocal of the variance associated with the estimate. Germination rates increased linearly with temperature between 15 degrees C and 30 degrees C for all species. Consistent estimates of Tbase were obtained for most species using several indices. The most statistically robust and biologically relevant method was the reciprocal time to median germination, which can also be used to estimate other biologically meaningful parameters. The mean Tbase for summer annuals (13.8 degrees C) was higher than that for winter annuals (8.3 degrees C). The two germination response characteristics, Tbase and slope (rate), influence a species' germination behaviour in the field since the germination inhibiting effects of a high Tbase may be offset by the germination promoting effects of a rapid germination response to temperature. Estimates of Tbase may be incorporated into predictive thermal time models to assist weed control practitioners in making management decisions.

This study examined the association between social relationship facilitation and affect. Young adults who did not know one another engaged in brief, get-acquainted conversations. Participants rated their positive affect and negative affect before and after conversations. After conversations, participants also rated their self-disclosure, social attraction to partners, and contribution to the conversation relative to their partners. In support of the hypotheses, positive affect increased from before to after conversations, and greater self-disclosure and social attraction predicted the increase in positive affect. A greater contribution, however, did not predict the increase in positive affect but did predict the significant decrease in negative affect. These results support Baumeister and Leary's (1995) proposed need for social relationships in which positive affect accompanies relationship facilitation.

The sky will soon be populated with a fleet of new X- and gamma-ray satellites with extraordinary capabilities. This paper is meant to introduce these new missions,Chandra, XMM, and Astro-E, which will provide a large fraction of our high energy “space observatory” functionality for the next decade.

The present study applied a script methodology from cognitive psychology to investigate schema content for threat in samples of individuals with spider phobia (n = 17), individuals with blood/injury phobia (n = 17), and nonanxious individuals (n = 30). Participants listed prototypical sequences of events, or scripts, that most people experience in threatening situations involving spiders or blood. Phobic participants generally listed similar events as nonanxious participants, although some deviant events characterized the aggregated script for the blood situation composed by spider phobics and the aggregated script for the spider situation composed by blood/injury phobics. Scripts for the scenario that corresponded to phobic participants' primary domain of fear reflected more discomfort than scripts composed by individuals in the other two groups. The results generally suggest that individuals with specific phobias have normative knowledge for feared situations, although underlying phobia proneness may facilitate the reporting of deviant schema content and affective tone in mildly threatening situations.

Abutilon theophrasti is one of the worst agricultural weeds in North America, yet it has not reached that status in California in the 80 yr since it was first reported. The research reported here examined the distribution and modeled climatic requirements of A. theophrasti to determine whether it is likely to spread more widely in the state. Herbaria records and weed literature were surveyed to determine the historical occurrences of A. theophrasti in the state; current distribution was assessed through surveys sent to University of California personnel in each county. Combined results showed 42 counties out of 58 with A. theophrasti present historically or currently. A plot of the cumulative number of counties containing A. theophrasti by decade fit a logistic equation. The maximum rate of spread of this species occurred in 1962 and it is likely that its final distribution by county in California is leveling off and not likely to increase further. The climate-matching/mapping software CLIMEX® wa...

Removal of Salmonella Enterica serovar enteritidis (S. enteritidis) circulating in the air can be important in reducing S. enteritidis problems in a flock. One potential method to aid in this removal is the use of a negative air ionizer. Such a device imparts a negative charge on airborne particles, causing them to be attracted to grounded surfaces, therefore, effectively taking them out of circulation. Two experiments were conducted to determine whether such a device could lower levels of S. enteritidis in a room containing infected caged laying hens. In both experiments, the negative air ionizer effectively decreased the room airborne levels of S. enteritidis compared to levels in a room lacking a device. This improvement was particularly evident in Experiment 2, in which the S. enteritidis reduction brought about by the ionizer averaged 96.5% during the last 6 days of the sampling period. Failure to brush dust off the ionizer every other day resulted in reduced efficiency. These results demonstrate the potential efficacy of negative air ionization in removing poultry bacterial pathogens in a layer room situation.

Objectives. The present study applied MacLeod, Mathews & Tata's (1986) dot probe attentional deployment methodology to individuals with specific phobias. Design. Attentional deployment towards spider-related, blood-related, positive, negative, and neutral words was examined. Method. Individuals with either spider phobia (N = 13) or blood/injury phobia (N = 14) and non-anxious controls (N = 14) completed the dot probe attentional deployment task. Results. Individuals with specific phobias did not demonstrate an attentional bias towards phobia-related stimuli relevant to their particular fears. Conclusion. Semantic-based information processing paradigms may not be sufficiently potent to demonstrate biased performance towards threatening stimuli in individuals with mild specific phobias who are otherwise healthy.

Minimum densities of Whitethroats Sylvia communis were estimated from 409 point counts at five sites in the Sahel zone of northern Nigeria during March–April 1995. Higher densities occurred in woodland than on farmland, open rangeland or semi-desert. Within woodland Whitethroats were seen more frequently in Balanites aegyptiaca than would be expected from its relative availability. Balanites aegyptiaca had the densest canopy and highest density of invertebrates, suggesting that the preference of Whitethroats for this tree may be because it offers the best protection from predators, heat and/or the best foraging opportunities. The presence or absence of Whitethroats within a point was, however, best predicted by high tree species diversity rather than foliage volume, canopy volume or tree density (though all of these factors were correlated). It seems likely, therefore, that diverse, relatively undegraded Sahelian woodland is a preferred habitat for Whitethroats during the spring migration period.

The three-dimensional ground state potential energy surfaces for He–Cl2, Ne–Cl2, and Ar–Cl2 have been calculated using the single and double excitation coupled-cluster approach with noniterative perturbational treatment of triple excitations [CCSD(T)]. Calculations have been performed with the augmented correlation consistent triple zeta basis sets supplemented with an additional set of bond functions. Single point calculations for approximate minima have also been performed with several other basis sets including the quadruple zeta basis set (aug-cc-pVQZ) with bond functions. For He–Cl2 and Ar–Cl2 the CCSD(T) results show that the linear configuration is lower in energy than the T-shaped one. For Ne–Cl2 the CCSD(T) approach predicts the T-shaped configuration to be lower in energy. The linear configuration has been found to be more sensitive than the T-shaped one to the changes of the Cl–Cl bond length with the interaction becoming weaker when the Cl–Cl bond length is shortened from its equilibrium value...

Arundo donax L. (giant reed) is an invasive perennial plant that has spread widely in riparian areas in California, where it has altered wildlife habitats, created a fire hazard, compromised water conservation efforts, and affected flood control. Currently, physical removal is the primary means of controlling this weed, which is ineffective because of prolific asexual reproduction from an extensive rhizome system. We conducted controlled experiments on the sprouting potential of vegetative propagules, effects of storage duration and conditions on sprouting, and survival and growth of propagules in various soil types and moisture regimens. Sprouting and regrowth varied greatly with propagule type and size and with treatment and duration of storage after removal from the plant. Over 90% of stem and rhizome pieces with at least one node sprouted. Stem sprouting was affected by prior storage duration, temperature and moisture, whereas only storage duration and moisture affected rhizome sprouting. Sprouting was reduced by drying propagules at 30 °C for 1 week and by storage in a soil slurry. After 16 weeks, even propagules maintained optimally in moist soil showed reduced sprouting. Rhizome pieces sprouted readily from a soil depth of 25 cm, whereas stem pieces sprouted from less than 10 cm. Responsiveness of asexual reproduction in A. donax to environmental cues suggests that mechanical control can be improved by careful timing and treatment of cut biomass pieces to minimize or inhibit sprouting.

Electrostatic space chargers were used to impart a negative charge to airborne dust particles and thereby cause them to be attracted to grounded surfaces. To determine whether negative air ionization could affect the airborne transmission of Salmonella enteritidis, chicks were housed in four controlled-environment isolation cabinets in which airflow was directed across an unoccupied central area from one ("upstream") group of birds to another ("downstream") group. Negative air ionizers were installed in two of these cabinets. In three replicate trials, groups of chicks were placed in the upstream ends of the transmission cabinets and orally inoculated with S. enteritidis at 1 wk of age. On the following day, 1-d-old chicks were placed in the downstream ends of the cabinets. When chicks were sampled at 3 and 8 d postinoculation, S. enteritidis was found on the surface of 89.6% of the downstream chicks from cabinets without negative air ionizers, but on only 39.6% of the downstream chicks in the presence of the ionizers. Similarly, S. enteritidis was recovered from the ceca of 53.1% of sampled downstream chicks in cabinets without ionizers, but from only 1.0% of the ceca of chicks in cabinets in which ionizers were installed. The presence of the ionizers was also associated with reduced levels of circulating airborne dust particles. Reducing airborne dust levels may thus offer an opportunity to limit the spread of S. enteritidis infections throughout poultry flocks.

To evaluate the effects of maintenance treatment and durability of gains after treatment discontinuation, responders to either phenelzine (PZ) or cognitivebehavioral group therapy (CBGT) from an acute trial comparing these two treatments as well as pill placebo and a psychotherapy control (educational supportive group therapy) were enrolled into maintenance and treatment-free follow-up phases. Experimental design: Responders to an acute trial contrasting PZ and CBGT entered a six-month maintenance phase. Patients who continued to respond through the maintenance phase entered a six-month treatment free phase. Patients receiving pill placebo or educational supportive group therapy in the acute trial did not enter the long term study. Principal observations: PZ patients entered maintenance more improved than CBGT patients, and nonrelapsing PZ patients maintained their superior gains throughout the study. Relapse during maintenance did not differ between treatments. However, PZ patients showed a trend toward greater relapse during treatment-free follow-up. There was a greater relapse among patients with generalized social phobia with phenelzine. Conclusions: PZ and cognitive-behavioral group therapy may differ in their long term effects. The superiority seen with PZ on some measures in the acute study persisted in patients who maintained their gains over the course of maintenance and treatment-free follow-up. However, CBGT may lead to a greater likelihood of maintaining response after treatment has terminated. Replication with larger samples is needed, as is a study of the acute and long-term efficacy of combined PZ and CBGT. Depression and Anxiety 10:89‐98, 1999. © 1999 Wiley-Liss, Inc.

This article is concerned with penalty methods for solving optimal Dirichlet control problems governed by the steady-state and time-dependent Navier-Stokes equations. We present, in two different versions, the penalized methods for solving the steady-slate Dirichlet control problems. These approaches are implemented and compared numerically. We also generalize the penalty methods to the time-dependent case. Scmidiscrete and fully discrete approximations of time-dependent Dirichlet control problems are discussed and implemented. Numerical results for solving both the steady-state and the time dependent Dirichlet control problems are reported.

The objective of the GREAT-ER project is to develop and validate a powerful and accurate aquatic chemical exposure prediction tool for use within the EU environmental risk assessment schemes. Current techniques to estimate regional PECs use a generic multimedia `unit world' approach and do not account for spatial and temporal variability in landscape characteristics, river flows and/or chemical emissions. Hence, the results are merely applicable on a generic screening level since these models do not offer a realistic prediction of actual steady-state background concentrations. In addition, the default EU generic regional environment (EU Technical Guidance Documents, 1996) only allows treatment for 70% of the waste water mass loading, leaving 30% of mass loading to this generic region untreated. A new database, model and software system will be developed to calculate the distribution of predicted environmental concentrations (PEC), both in space and time, of down the drain chemicals in European surface waters on a river and catchment area level. Data on dissolved oxygen, biological oxygen demand and ammonia will also be used to assess water quality and to provide data for calibration and validation. The system will use Geographical Information Systems (GIS) for data storage and visualization, combined with simple mathematical models for prediction of chemical fate. Hydrological databases and models will be used to determine flow and dilution data. This refined exposure assessment tool should greatly enhance the accuracy of current local and regional exposure estimation methods. The new exposure assessment methodology will integrate specific environmental information and be worked out in a geographically-referenced framework, ultimately on a pan-European scale. This research project is carried out on behalf of ECETOC, and sponsored by the Environmental Risk Assessment Steering Committee (ERASM) of the Association Internationale de la Savonnerie, de la Detergence et des Produits d'Entretien (A.I.S.E.) and the Comite Europeen de Agents de Surface et Intermediares Organiques (CESIO) in cooperation with the UK Environment Agency.

Socially anxious people often report high negative affect (NA) and low positive affect (PA). This mood state may be associated with elevated or undesired social evaluation, such as interactions with unfamiliar people or poor quality communication. In this study, high and low anxious undergraduates completed structured diaries assessing interaction partner familiarity, quality of communication, PA, and NA after conversations in their natural environment. Results supported hypotheses of higher NA and lower quality of communication intheanxiousgroup. In addition, quality of communication and familiarity were differently related to NA in the high versus low anxious groups. Results suggest that social-interaction parameters affect high anxious individuals' mood. Implications of the current social interaction based results are contrasted with time-interval diary research.

The results of a linear alkylbenzene sulphonate (LAS) monitoring exercise carried out during August and September, at six different trickling filter sewage treatment plants in the Aire and Calder catchments in the UK are described. The average LAS concentration in flow proportional, composite, crude sewage was 3.25 mg l−1 and ranged from 1.10 to 5.58 mg l−1. Based on consumer usage data and boron measurements these results indicate that up to 60% of the LAS was removed in the sewers prior to reaching the sewage treatment plants. The concentration of LAS in flow proportional, composite final effluents from well-operated plants ranged from 4 to 460 μg l−1, with an average value of 240 μg l−1. Removal through the plants ranged from 70–99% with mean values of 90.7, 93.4, 93.0, 74.6, 97.3 and 92.4% for the six plants. A simple model is described which can be used to accurately predict the diel variation in LAS concentrations in the final effluent when measured influent concentrations, flow and settling tank volumes are known.

Based on concomitant time-series analyses, the results of this study support distinct social interaction correlates for the mood dimensions of negative affect (NA) and positive affect (PA). Participants (N = 25) completed structured diaries three times daily for 4 weeks assessing their PA, NA, and participation in five types of social interaction. A significant number of participants' data series evidenced significant positive correlations between PA and fun/active and necessary/informational types of social interaction, and between NA and arguing/confronting and receiving help/support, during synchronous diary periods. Providing help/support was not related to NA or PA. No hypothesized time-lagged relations between mood and social interaction variables were present suggesting that, if these associations exist, they may be at intervals shorter than the one third day recording frequency used in this study. Results are discussed in the context of research on mood, social interaction, and time-series analysis.

An extensive monitoring programme was conducted in seven Dutch municipal sewage treatment plants to determine the environmental concentrations of the main types of surfactants, including linear alkylbenzene sulphonate (LAS), alcohol ethoxylates (AE), alcohol ethoxy sulphates (AES), alcohol sulphates (AS) and soap. All surfactants were removed by more than 99% during sewage treatment. The concentrations of the surfactants in the treated sewage averaged 39 μg/l for LAS, 6.2 μg/l for AE, 6.5 μg/l for AES, 5.7 μg/l for AS and 174 μg/l for soap. The measured effluent concentrations were used to determine the frequency distribution of surfactants in the receiving river water. In addition the monitoring study demonstrated that a significant part of the surfactants were degraded in the sewer.

Salmonella pullorum is a host-adapted pathogen of poultry previously thought to be nonmotile and nonflagellated. We discovered that motility can be induced in this organism under special medium conditions, and this motility was observed in 39 of 44 S. pullorum isolates tested. The migration appeared to occur only on the medium surface and not within the medium itself, indicating that swimming may not be responsible for this event. Agar concentration, carbohydrate concentration and type, and temperature of incubation all affected the motility. Flagellar stains and transmission electron micrographs of the motile S. pullorum culture showed long fibrous appendages resembling flagella extending from the cells, but these appendages were thinner and less numerous than the flagella observed on Salmonella enteritidis. Antisera to G flagellar antigens reacted strongly with the induced-motility S. pullorum culture, indicating that G epitopes were expressed on these cells. These results indicate that, contrary to the paradigm which held that S. pullorum is nonmotile and nonflagellated, motility can be induced in S. pullorum and that the organism appears to have the capacity to produce flagella.

We illustrate the current status of the application of computer modelling methods to catalytic systems by taking recent examples from modelling of both long range and local structural properties of microporous materials, surface structures of oxides, sorption in zeolites, host-template interactions in aluminophosphates and reaction mechanisms on oxide surfaces and at acid sites in zeolites. We emphasise the role of modelling techniques in the interpretation of experimental studies in catalysis.

Older leghorn hens, more than 50 weeks of age, were divided into three groups designated 1, unmolted controls; 2, molted; or 3, molted treated with lactose. Forced molt was induced by 14 days of feed removal. Lactose was provided to the hens in group 3 as 2.5% (wt/vol) of the daily drinking water. Each hen in all groups was challenged orally with 10 5 Salmonella enteritidis (SE) cells on day 7 of feed removal. The study was repeated in three replicated trials. The concentrations of acetic, propionic, and total volatile fatty acids (VFA) in the cecal contents of the molted hens in groups 2 and 3 decreased significantly (P < 0.05) on days 6 and 14 of molt compared with the unmolted controls. Forced molt had no apparent effect on pH or on the oxidation-reduction potential of the ceca. Compared to the unmolted controls, SE cecal and spleen and liver colonization was significantly increased (P < 0.05) in the molted hens in group 2. Compared to the molted hens in group 2, SE cecal and spleen and liver colonization was significantly decreased (P < 0.05) in two of three trials in the hens in group 3 provided with lactose. The results suggested that the increased susceptibility of molting hens to SE colonization may be associated with decreased fermentation and production of VFA by cecal bacteria or by a depletion of the number of VFA-producing bacteria present in the ceca. The results further suggest that providing lactose in the drinking water during molting may significantly enhance resistance to SE colonization.

An all solid-state high power microwave system comprised of a photoconductive semiconductor switch (PCSS) and nonlinear transmission line (NLTL) is presented. A single 50 kV 4H-Silicon Carbide (SiC) PCSS switches 7 ns (FWHM) pulses with 2 ns risetime into the gyromagnetic NLTL. The PCSS achieves sub-ohm resistance when illuminated by approximately 3 mJ of laser energy emitted from a tripled Nd:YAG laser (355 nm). Utilizing a fiber optic based optical triggering system enabled generating a train of laser pulses, and burst-mode operation with 65 MHz pulse repetition frequency was achieved. The NLTL sharpens the fast rising pulse from the PCSS and produces MW-class rf power levels at 2-4 GHz. Microwave generation is achieved through stimulation of damped gyromagnetic precession when the static and pulsed external magnetic fields interact with the magnetic moments of the nonlinear ferromagnetic material. The acting nonlinear material is a NiZn composite with dimensions 3 mm × 6 mm (ID × OD). The system is terminated with a wideband antenna consisting of a coaxial to parallel-plate conversion balun which is then immediately flared to provide a linearly-flared TEM horn antenna. The entire length of the compact HPM system measures 1.15 m. Radiation results for single shot and burst-mode operation are presented as well as demonstration of operational frequency control.

Summary form only given. Recent work on Coaxial Ferrimagnetic Nonlinear Transmissions Lines (NLTL) has been focused on developing an array of NLTLs for use as a solid-state High Power Microwave (HPM) source. The pulsed output of an NLTL requires a combiner that enables combining transient signals at voltage levels up to 50 kV. Existing combiner designs found in literature require resonant structures to achieve efficient power combination, an approach that fails for the short pulse transient signals generated by the NLTL. The novel coaxial combiner is an in-plane structure designed to combine two 50 Ω NLTLs into a single 25 Ω coaxial output which then uses a linear taper to transition back to 50 Ω. The combiner design was simulated using a transient Finite Element Method (FEM) model in COMSOL Multiphysics® and experimental results are compared with simulation. A four-way radial combiner based on the in-plane two-way design is simulated and the field stresses are examined to determine possible operational voltage levels for the four-way design.

Coaxial Ferrimagnetic Nonlinear Transmission Lines (NLTL) are utilized as all solid state High Power Microwave (HPM) sources with virtually fixed phase relationship between input voltage pulse and output rf wave. Since the output power of a single NLTL at a given frequency, and of a given size, is limited by the effect of line dimensions as well as charge voltage on operating frequency, we employ an NLTL array to achieve higher power levels. To operate in microwave generation mode the ferrite domains are aligned along the axial direction of the NLTL using a biasing magnetic field generated by a dc current driven solenoid. This biasing method also provides a means of controlling the line delay by adjusting the magnetization of the ferrites using an auxiliary delay coil. By utilizing the delay coil and the primary biasing coil together on an NLTL, the operating frequency can be locked at a given frequency while the delay of the line can be independently adjusted. The relationship between the delay coil field and the corresponding temporal delay is investigated, and two NLTLs fed by identical voltage pulse shapes are combined using the phase control method described.

At the Center for Pulsed Power and Power Electronics, previous coaxial ferrimagnetic Nonlinear Transmission Lines (NLTL) relied solely on pressurized Sulfur Hexafluoride (SF6) as high-voltage insulating dielectric medium [1]. While the use of SF6 provides the necessary electric insulation, there are drawbacks including gas storage and pressure fittings that increase system size and add to the design complexity of the NLTLs themselves. Hence it was deemed necessary to evaluate solid dielectric materials as an alternative. Initial attempts utilized a standard high voltage (HV) epoxy to pot the NLTL assembly. This method was effective at producing magnetic precession in the NLTL; however, there was a reduction in output power due to the high loss tangent of the epoxy. Sylgard 184, commonly used in solar cells, has also found use as an HV potting material. Per datasheet, its loss tangent is an order of magnitude lower compared to standard HV epoxy at 1 kHz. Samples of HV epoxy and Sylgard 184 were tested in a microwave cavity resonator at 3GHz, which yielded their respective loss tangents. The performance of an NLTL potted with Sylgard 184 is compared to that of the HV epoxy NLTL and the earlier SF6 insulated NLTL.

The design of a scalable, burst-mode rapid capacitor charger and a high power battery system will be discussed. The design is scalable up to 40 kW output power and operates at 50 k V. The system is powered by a Lithium Ion Polymer (LiPo) battery pack and includes a battery management system. The topology is derived from a 5 kV, 3 kJ/s battery power capacitor charger that was previously demonstrated. This smaller charger occupied a volume of 1.5 L including batteries and demonstrated a 2 kW/L average power density over a 1 s burst. This power density is five to ten times higher than commercially available systems. The performance of this previous design was limited by strict form factor restrictions (1.5 L, 6" diameter). The new design is intended to match or exceed the power density of the previous design due to reduced form factor restrictions. Electrical and mechanical design, component selection, and circuit simulations will be presented.

Before pharmaceutical products are evaluated in humans, it is essential that they undergo a rigorous safety assessment using in vitro models and studies in preclinical species. Once products progress into the clinic, additional preclinical studies are needed to support further clinical testing. Although regulatory guidelines provide a good framework for the types of studies that should be performed, there are some areas where it is unclear how these should be applied to microbicides, what study designs should be used, whether certain tests are relevant or if additional assays are appropriate. In this chapter we provide an overview of the key issues for the preclinical development of microbicides, and describe the purpose of each of the tests along with the key considerations to be taken into account when designing the individual safety studies as well as the overall preclinical program.

Studies have identified endoglin as a biological marker that is overexpressed on the microvessels of certain solid cancers (breast, colorectal cancer, and head and neck squamous cell cancers). There is, at present, no immunohistochemical marker that can discriminate between lymph node-negative and or lymph node-positive breast cancer tissue.The expression of endoglin was quantified by immunohistochemistry and assessment of microvessel density in 53 surgical specimens. These were comprised of breast tumor tissue that had not spread to the regional lymph nodes (lymph node-negative breast tumor tissue: 20 specimens), breast tumor tissue had spread to regional lymph nodes (lymph node-positive breast tumor tissue: 21 specimens), and normal breast tissue as a control (12 specimens).Significant difference was observed between the expression of endoglin on microvessels of lymph node-negative and lymph node-positive breast cancer tissue (p0.05). This significant difference was shown to be due to endoglin expression on lymphatic vessels (p0.02), rather than on blood vessels (p0.05).These findings are the first to suggest that endoglin expression on breast tumor lymphatic vessels may have diagnostic potential as a discriminator between lymph node-negative and lymph node-positive breast cancer. Further studies would be required to confirm this.

Before pharmaceutical products are evaluated in humans, it is essential that they undergo a rigorous safety assessment using in vitro models and studies in preclinical species. Once products progress into the clinic, additional preclinical studies are needed to support further clinical testing. Although regulatory guidelines provide a good framework for the types of studies that should be performed, there are some areas where it is unclear how these should be applied to microbicides, what study designs should be used, whether certain tests are relevant or if additional assays are appropriate. In this chapter we provide an overview of the key issues for the preclinical development of microbicides, and describe the purpose of each of the tests along with the key considerations to be taken into account when designing the individual safety studies as well as the overall preclinical program.