Search

The construction of MITICA, the full-size prototype of the ITER Heating Neutral Beam Injectors (HNBs) is in progress at the Neutral Beam Test Facility (NBTF) located in Padova, Italy. The design of the central control (CODAS) and interlock (CIS) systems is progressing taking into account the requirements coming from the MITICA plant units, in terms of number and type of interface signals, data sampling frequency values, operating states, protection actions and required reaction times and reliability. As the HNBs will be ITER components, additional requirements derive from the ITER plant control design handbook that specifies the design criteria and standard technologies to be applied to ITER plant systems. A distinction must be made in MITICA between plant units that will be part of the HNB, such as the power supply systems, and plant units that are auxiliaries, such as the gas and vacuum system. In the NBTF these components shall interface with MITICA CODAS and CIS, whereas in ITER they will be autonomous plant systems providing services to the HNB. The distinction reported above suggests defining the architecture of MITICA Instrumentation and Control (I&C) as split into the following functional blocks: i) HNB plant system including components that will be part of the HNB; ii) Service plant system including all operational plant units that need control in the NBTF but are implemented outside the ITER HNB; iii) Diagnostics plant system; iv) Central I&C (CODAS and CIS). The paper presents the requirements for MITICA CODAS and CIS and derives from these the system architecture. The design of CODAS and CIS is discussed with reference to the lesson learned in the implementation of SPIDER CODAS and CIS (the NBTF ion source test bed) and to the technologies suitable for the implementation.

In this work, a deep learning approach has been developed to carry out road detection by fusing LIDAR point clouds and camera images. An unstructured and sparse point cloud is first projected onto the camera image plane and then upsampled to obtain a set of dense 2D images encoding spatial information. Several fully convolutional neural networks (FCNs) are then trained to carry out road detection, either by using data from a single sensor, or by using three fusion strategies: early, late, and the newly proposed cross fusion. Whereas in the former two fusion approaches, the integration of multimodal information is carried out at a predefined depth level, the cross fusion FCN is designed to directly learn from data where to integrate information; this is accomplished by using trainable cross connections between the LIDAR and the camera processing branches. To further highlight the benefits of using a multimodal system for road detection, a data set consisting of visually challenging scenes was extracted from driving sequences of the KITTI raw data set. It was then demonstrated that, as expected, a purely camera-based FCN severely underperforms on this data set. A multimodal system, on the other hand, is still able to provide high accuracy. Finally, the proposed cross fusion FCN was evaluated on the KITTI road benchmark where it achieved excellent performance, with a MaxF score of 96.03%, ranking it among the top-performing approaches.

The ITER Plasma Control System (PCS) approaching the second phase of development is now more deeply investigating alternative solutions for the various controls aimed at operations up to 15MA with low auxiliary heating in L-mode. The control functions in the PCS are strictly linked to the performance of the ITER actuators and diagnostics. The capabilities of those systems need to be carefully validated against the control needs. System and performance requirements shall be consistent with the control schemas and where limitations or restrictions are identified, it is necessary to provide alternative solutions. To guarantee this consistency, a set of interface documents is being prepared. Those interfaces for each of the plant systems that can impact the PCS activities detail the requirements specifically needed for control and report also the functional relationship between the two systems. The PCS has also to consider areas not actively part of plasma control that might affect or limit PCS operations (i.e. forces in the superconducting coils). This paper reports the main outcome from the interfaces definition. The actuator boundaries and plant systems constraints impacting the PCS design will be presented. For the sensors the challenge is the derivation of real-time measurement requirements in relation to the separate diagnostic requirements and their respective interface with the PCS. The complex organization of data integration with the PCS will be discussed.

The SPIDER central interlock is a centralized electronic system to coordinate the protection functions within the SPIDER experiment (Source for the Production of Ions of Deuterium Extracted from an RF plasma), i.e. the full-size ion source prototype of the ITER Neutral Beam Injector. Due to the system time requirements, the SPIDER central interlock has been implemented by using PLCs for the slow functions (100 ms reaction time from fault detection to protection command emission) and National Instruments CompactRIO for the fast functions (10 μs from fault detection to command emission). The paper describes in detail the system hardware and software implementation. The results of the first tests and commissioning are reported with particular focus on the implementation, execution, and performance of the interlock fast functions.

Background The COVID-19 pandemic has highlighted the need for rapid, cost effective and easy-to-use diagnostic tools for SARS-CoV-2 infections that can be used in point of care settings to limit disease transmission. Objective We evaluated two rapid antigen immunochromatographic tests, Abbott Panbio™ COVID-19 Ag Rapid Test (Panbio) and Zhejiang Orient Gene/Healgen Biotech Coronavirus Ag rapid test cassette (Orient gene) for detection of infectious SARS-CoV-2. Results The tests were evaluated on nasopharyngeal samples taken from individuals having respiratory and/or COVID-19 related symptoms, which had been analyzed for SARS-CoV-2 RNA using real-time PCR. In total 156 PCR-positive, and 130 (Panbio) and 176 (Orient Gene) PCR-negative samples were analyzed. Overall sensitivity and specificity were 71.8% and 100% for Panbio and 79.5% and 74.4% for the Orient Gene test respectively. The false positives by the Orient Gene test were verified as SARS-CoV-2 negative by in-house real-time PCR assay and were negative for the four seasonal coronaviruses. Subgroup analysis revealed that the antigen tests had high sensitivity for samples with Ct-values 88%) and for samples containing infectious viruses as determined by cultivation on Vero cells, 94.1% and 97.1% for the Panbio and Orient gene tests, respectively. Furthermore, both tests had a sensitivity of 27 was shown to contain infectious virus. Conclusion The results indicate that the rapid antigen tests, especially the Panbio tests may be a valuable tool to detect contagious persons during the ongoing pandemic.

This paper focuses on the update step of Bayesian nonlinear filtering. We first derive the unscented Gaussian likelihood approximation filter (UGLAF), which provides a Gaussian approximation to the likelihood by applying the unscented transformation to the inverse of the measurement function. The UGLAF approximation is accurate in the cases where the unscented Kalman filter (UKF) is not and the other way round. As a result, we propose the adaptive UGLAF (AUGLAF), which selects the best approximation to the posterior (UKF or UGLAF) based on the Kullback-Leibler divergence. This enables AUGLAF to outperform both the UKF and UGLAF.

The neutral beam (NB) system for ITER is composed of two heating neutral beam injectors (HNBs) and a diagnostic neutral beam injector (DNB). A third HNB can be installed as a future up-grade. This paper will present the design development of the components between the injectors and the tokamak; the so-called ‘front end components’: the drift duct consists of the NB bellows and the drift duct liner, the vacuum vessel pressure suppression system box (VVPSS box), the absolute valve, and the fast shutter. These components represent the key links between the ITER tokamak and the vessels of the NB injectors. The design of these components is demanding due to the different loads that these components will have to stand. The paper will describe the different design solutions which have to be implemented regarding the primary vacuum confinement, the power handling capability and the remote maintenance operations. The sizes of the components are determined by the large cross section of the neutral beam. The power handling capability is driven by the anticipated re-ionization of the neutral beam and the electromagnetic fields in this region. The drift duct bellows (with an inner diameter of 2.5 m) shall guarantee a leak tight vacuum enclosure during the vertical and radial displacements of the ITER vacuum vessel. The conductance of the VVPSS box must be maximized in the available space. The absolute valve remains a challenging development. The total leak rate through the valve must be ≤1 × 10−8 Pa m3/s when the valve is closed. Due to the radiation environment, the seals of the gate valve will be metallic. An R&D program has been launched to develop a suitable metallic seal solution with the required dimensions. The maximum allowed closing time for the fast shutter shall be less than 1 s. For all these components the leak tightness will be guaranteed by a welded lip seal and the mechanical stability by bolted structures.

CEA has undertaken tests to study the resilience of copper electrodes in vacuum against energetic high-voltage breakdowns using external capacitors to provide the energy. Earlier tests succeeded in dissipating a maximum of 150 J in a 30 mm gap, limited by the equivalent series resistance (ESR) in the external capacitors. Using new ones with an ESR that is a factor of 10 lower it was unsuccessfully tried to produce breakdowns at 200 kV over the 85 mm gap, despite the use of a UV flash lamp and a “field enhancement ring” (FER) that locally increased the electric field on the cathode by 50%. Consequently, the breakdowns had to be produced by raising the voltage to 300–350 kV while maintaining the gap at 85 mm. During these tests, single breakdowns dissipated up to 1140 J in the 85 mm vacuum gap. Inspection of the electrodes revealed that substantial amounts of copper appear have been evaporated from the anode and deposited on to the cathode. Also electrode deconditioning occurred.

The HV bushing has a function of a bulk head between insulation gas (SF6) of 0.6 MPa and vacuum, which is needed to insulate −1 MV in vacuum in ITER heating neutral beam (NB) injection system. Mechanical analyses were carried out to verify the mechanical integrity of the HV bushing composed of five-stage double-layered insulator columns with large brazed ceramic ring and fiber reinforced plastic (FRP) ring of which non-metallic material is required to satisfy a safety factor of ≥3.5. As for the FRP ring required sustaining the pressure load, seismic load and dead weight, it was confirmed that isotropic fiber cloth FRP rings having sufficient strength against shear stress should be used. The shape and fixation area of the Kovar sleeve were modified to lower the stress at the brazing area having vacuum leak tightness and pressure tightness against the air filled at 0.6 MPa. As a result, a design of the insulator for the HV bushing was established satisfying the requirement.

Group A rotavirus (RVA) is the most common cause of severe gastroenteritis in young children globally, and responsible for a significant number of deaths in African countries. While vaccines are available, trials have shown a lesser efficacy in Africa. One of the reasons could be the prevalence and/or emergence of unusual or novel RVA strains, as many strains detected in African countries remain uncharacterized. In this study, we characterized RVA positive specimens from two remote rural areas in Burkina Faso, West Africa. In total 56 RVA positive specimens were subgrouped by their VP6 gene, and G-and P typed by PCR and/or sequencing of the VP7 and VP4 genes, respectively. Notably, we found a high prevalence of the unusual G6P[6]SGI strains (23%). It was the second most common constellation after G9P[8]SGII (32%); and followed by G1P[8]SGII (20%) and G2P[4]SGI (9%). We also detected a G8P[6]SGI strain, for the first time in Burkina Faso. The intra-genetic diversity was high for the VP4 gene with two subclusters within the P[8] genotype and three subclusters within the P[6] genotype which were each associated with a specific G-type, thereby suggesting a genetic linkage. The G6P[6]SGI and other SGI RVA strains infected younger children as compared to SGII strains (p

While the clinical importance of human rotavirus (RV) disease is well recognized and potent vaccines have been developed, our understanding of how human RV causes diarrhoea, vomiting and death remains unresolved. The fact that oral rehydration corrects electrolyte and water loss, indicates that enterocytes in the small intestine have a functional sodium-glucose co-transporter. Moreover, RV infection delays gastric emptying and loperamide appears to attenuate RV diarrhoea, thereby suggesting activation of the enteric nervous system. Serotonin (5-HT) receptor antagonists attenuate vomiting in young children with gastroenteritis while zinc and enkephalinase inhibitors attenuate RV-induced diarrhoea. In this review we discuss clinical symptoms, pathology, histology and treatment practices for human RV infections and compile the data into a simplified disease model.

The particle filter (PF) has emerged as a powerful tool for solving nonlinear and/or non-Gaussian filtering problems. When some of the states enter the model linearly, this can be exploited by using particles only for the "nonlinear" states and employing conditional Kalman filters for the "linear" states; this leads to the Rao-Blackwellised particle filter (RBPF). However, it is well known that the PF fails when the state of the model contains some static parameter. This is true also for the RBPF, even if the static states are marginalised analytically by a Kalman filter. The reason is that the posterior density of the static states is computed conditioned on the nonlinear particle trajectories, which are bound to degenerate over time. To circumvent this problem, we propose a method for targeting the posterior parameter density, conditioned on just the current nonlinear state. This results in an RBPF-like method, capable of recursive identification of nonlinear dynamical models with affine parameter dependencies.

The ITER Neutral Beam (NB) System consists of a 100 keV diagnostic injector (DNB) and two 1 MeV heating and current drive injectors (HNB). Injection will be done in the different phases of the experimental programme, ranging from low activation operation with hydrogen and helium plasmas, deuterium plasmas, and finally full performance operation with deuterium–tritium mixtures. The injectors will be operated in a harsh environment with high levels of neutron and gamma radiation from the torus. A high stray magnetic field from the tokamak is reduced to acceptable levels for the region up-stream of the residual ion dump (RID) by a combination of a passive magnetic shield and active correction and compensation coils (ACCC). This broad range of requirements imposes a high flexibility, a high availability and reliability of the instrumentation and on the diagnostics that will be used.

Objective: There is limited information available regarding the etiology of gastrointestinal infections in Burkina Faso. The aim of this study was to investigate the prevalence and epidemiology of enteric pathogens causing gastroenteritis in young children, with a focus on rotavirus, and to investigate the levels of malnutrition and other clinical factors in association with the severity of diarrhea. less thanbrgreater than less thanbrgreater thanMethods: A prospective study was undertaken from May 2009 to March 2010, covering the rainy and dry seasons, at the Saint Camille Medical Center in Ouagadougou, Burkina Faso. A total of 309 children less than 5 years of age with diarrhea were enrolled and examined for rotavirus, bacterial, and parasitic infections, as well as clinico-epidemiological aspects. less thanbrgreater than less thanbrgreater thanResults: At least one enteropathogen was detected in 57.9% (n = 179) of the children. Of these, 32.4% had rotavirus infections, 16.8% bacterial infections (enteropathogenic Escherichia coli 9.7%, Shigella spp 5.8%, and Salmonella spp 2.3%), and 18.8% parasitic infections (Giardia lamblia 11.3%, Trichomonas intestinalis 6.8%, Entamoeba histolytica/dispar 1.3%). During the cold dry period from December 2009 to February 2010, we observed a large increase in diarrhea cases, which was mainly attributed to rotavirus infections, as 63.8% of these diarrhea cases were positive for rotavirus. In contrast, no rotavirus infection was observed during the rainy season (June-September 2009), when the frequency of parasitic infections was high. Rotavirus and parasitic infections were age-related, with rotavirus being more prevalent in young children (andlt;12 months) and parasites more common in older children (andgt;12 months), while bacteria were equally prevalent among all age groups. Rotavirus infections exhibited more severe symptoms compared to bacteria and parasites, and were associated with fever, vomiting, and severe dehydration. Malnutrition, especially acute malnutrition (wasting), was significantly associated with more severe symptoms in rotavirus-induced diarrhea. The undernourished children also exhibited a prolonged duration of diarrheal episodes. less thanbrgreater than less thanbrgreater thanConclusion: This study demonstrates rotavirus as the main etiological agent in pediatric diarrhea in Burkina Faso, and further shows the great severity of rotavirus-induced diarrhea in undernourished children in Burkina Faso.

Beam experiments and calculations aimed at characterising and suppressing the negative deuterium ion beam halo have been performed at IRFM, CEA-Cadarache. Using a “classic” plasma grid, we established that no halo ( We hypothesized that significant halo originates from negative ions being formed on the metal parts of the plasma grid (as could happen when neutral atoms from the source hit the plasma grid covered with caesium). Based on this hypothesis we tested a new design for the plasma grid, aimed at substantially reducing the halo. The test was successful and the halo was reduced from 8% to 3%. The single beamlet profiles show an asymmetry that is caused by the presence of the electron suppression magnets in the accelerator.

A well established theory proposes that glutamate signalling via the NMDA receptor is compromised in patients with schizophrenia. Deficits related to NMDA receptor signalling can be observed in several brain regions including the prefrontal cortex (PFC), an area extensively linked to the cognitive dysfunction in this disease and notably affected by NMDA receptor antagonists such as phencyclidine (PCP). In addition, a number of studies suggest that normalizing of PFC function could constitute a treatment rationale for schizophrenia. To further study the role of PFC function we investigated the effect of local PFC NMDA receptor blockade on impaired prepulse inhibition (PPI) induced by systemic administration of PCP. Mice received prefrontal injections of PCP (0.01, 0.1 or 1 mM) before PCP treatment (5 mg/kg) and were thereafter tested for PPI. PCP induced deficits in PPI were ameliorated by prefrontal PCP (0.1 mM) treatment whereas PPI was not affected by prefrontal cortex PCP administration per se at any of the doses tested. Taken together, inhibition of NMDA receptors in the PFC does not seem to be enough to impair PPI per se but NMDA receptor mediated signalling in the PFC may be a key factor for the PPI-disruptive effects of global NMDA receptor inhibition. This indicates that targeting PFC NMDA receptor signalling may have potential as a treatment target for schizophrenia although further studies are needed to understand pharmacology and pathophysiological role of PFC NMDA receptors.

IRFM (CEA Cadarache) and JAEA Naka have entered into a collaboration in order to test a Single Gap, Single Aperture (SINGAP) [H.P.L. de Esch, R.S. Hemsworth, P. Massmann, Updated physics design ITER-SINGAP accelerator, Fusion Eng. Des. 73 (2005) 329.] accelerator at the JAEA Megavolt Test Facility (MTF) at Naka, Japan. Whereas at the CEA testbed the acceleration current was limited to 0.1 A, at JAEA 0.5 A is available. This allows the acceleration of 15 H − beamlets in SINGAP to be tested and a direct comparison between SINGAP and Multi Aperture, Multi Grid (MAMuG) [M. Taniguchi, T. Inoue, N. Umeda, M. Kashiwagi, K. Watanabe, H. Tobari, M. Dairaku, K. Sakamoto, Acceleration of ampere class H − ion beam by MeV accelerator, Rev. Sci. Instrum. 79 (2008) 02C110.] to be made. High voltage conditioning in the SINGAP configuration has been quite slow, with 581 kV in vacuum achieved after 140 h of conditioning. With 0.25 Pa of H 2 gas present in the accelerator 787 kV could be achieved. The conditioning curve for MAMuG is 200 kV higher. SINGAP beam optics appears in agreement with calculation results. A beamlet divergence better than 5 mrad was obtained. SINGAP accelerates electrons to a higher energy than MAMuG. Measurements of the power intercepted on one of the electron dumps have been compared with EAMCC code [G. Fubiani, H.P.L. de Esch, A. Simonin, R.S. Hemsworth, Modeling of secondary emission processes in the negative ion based electrostatic accelerator of the International Thermonuclear Experimental Reactor, Phys. Rev. ST Accel. Beams 11 (2008) 014202.] calculations. Based on the experiments described here, electron production by a SINGAP accelerator scaled up to ITER size was estimated to be too high for comfort.

Denna artikel har har blivit nominerad till EARLI publication award. Vinnare utses i Amsterdam den 25 augusti. This article has been nominated to the EARLI publication award. The winner will be announced in Amsterdam on the 25th of August.

Noroviruses have emerged as a major cause of acute gastroenteritis in humans of all ages. Despite high infectivity of the virus and lack of long-term immunity, volunteer and authentic studies has suggested the existence of inherited protective factors. Recent studies have shown that histo-blood group antigens (HBGAs) and in particular secretor status controlled by the α1,2fucosyltransferase FUT2 gene determine susceptibility to norovirus infections, with nonsecretors (FUT2-/-), representing 20% of Europeans, being highly resistant to symptomatic infections with major strains of norovirus. Moreover, the capsid protein from distinct strains shows different HBGA specificities, suggesting a host-pathogen co-evolution driven by carbohydrate-protein interactions. © 2006.

Obesity has been proposed to be a result of an imbalance in the physiological system that controls and maintains the body energy homeostasis. Several G-protein coupled receptors (GPCRs) are involved in the regulation of energy homeostasis. To investigate the importance of GPCR12, mice deficient of this receptor (GPCR12 KO) were studied regarding metabolism. Expression of GPCR12 was found primarily in the limbic and sensory systems, indicating its possible involvement in motivation, emotion together with various autonomic functions, and sensory information processing. GPCR12 KO mice were found to have higher body weight, body fat mass, lower respiratory exchange ratio (RER), hepatic steatosis, and were dyslipidemic. Neither food intake nor energy in faeces was affected in the GPCR12 KO mice. However, lower energy expenditure was found in the GPCR12 KO mice, which may explain the obesity. In conclusion, GPCR12 is considered important for the energy balance since GPCR12 KO mice develop obesity and have lower energy expenditure. This may be important for future drugs that target this receptor.

Accurate vehicle motion models are of essential importance for modern car safety systems, as they enable more precise tracking and prediction of the traffic. During normal driving, the driver controls the vehicle almost completely, yet, standard models, such as the constant acceleration kinematic model, fail to acknowledge the impact of the driver. In this paper, we propose a modified version of the above mentioned model, in which the effect of the driver is introduced as an additional acceleration. To calculate this acceleration, we approximate the driver with an optimal regulator, and derive an optimal trajectory through which the acceleration can be found. Our definition of an optimal trajectory, is such that resulting path should be both comfortable, safe, fast and legal. Simulations indicate that the new model can lead to significant gains in both tracking and prediction performance.

Latent inhibition (LI) is a behavioural procedure used to evaluate the potential propsychotic and antipsychotic properties of psychoactive drugs. In the present study, a conditioned taste aversion (CTA) procedure was used to investigate the effects of the nitric oxide (NO) synthase inhibitor, N G -nitro- l -arginine methyl ester (L-NAME), and the psychotomimetic drugs, phencyclidine (PCP) and d-amphetamine (d-AMP) on LI. PCP (2 mg/kg) and d-AMP (0.5 mg/kg) were both found to enhance LI in this procedure. The effect of d-AMP on LI was less pronounced and this drug also caused a weak disruption of taste aversion conditioning. Pretreatment with L -NAME (10 mg/kg) blocked the LI enhancing effect of PCP on LI but not that of d-AMP. L -NAME by itself caused an attenuation of LI. L -NAME has been shown to block also other behavioural and biochemical effects of PCP in previous studies and these results and the present findings suggest that at least some of the effects PCP are dependent on NO and possibly also that some NOS inhibitors may exert antipsychotic properties.

It is well recognized that the hypothalamus is of central importance in the regulation of food intake and fat mass. Recent studies indicate that it also plays an important role in the regulation of bone mass. Melanin concentrating hormone (MCH) is highly expressed in the hypothalamus and has been implicated in regulation of energy homeostasis. We developed MCHR1 inactivated mice to evaluate the physiological role of this receptor. Interestingly, the MCHR1−/− mice have osteoporosis, caused by a reduction in the cortical bone mass, while the amount of trabecular bone is unaffected. The reduction in cortical bone mass is due to decreased cortical thickness. Serum levels of c-telopeptide, a marker of bone resorption, are increased in MCHR1−/− mice, indicating that the MCHR1−/− mice have a high bone turnover osteoporosis. In conclusion, the MCHR1−/− mice have osteoporosis, indicating that MCHR1-signalling is involved in a tonic stimulation of bone mass.

The SINGle Aperture—SINgle GAP (SINGAP) acceleration concept has been developed as a simplified alternative to the Multi-Aperture, Multi-Grid (MAMuG) acceleration of the ITER Neutral Beam reference design. The objective of the present experiments is to demonstrate reliable multi-second acceleration of a D − beam to 1 MeV (∼100 mA, 200 A/m 2 ), relevant to the ITER neutral beam injection (NBI) requirements. During the previous studies it has been demonstrated that the SINGAP concept works and good quality 860 keV H − beams (43 mA, 1 s) and 630 keV D − beams (106 mA, 1 s) have been produced. In the present R&D programme another attempt has been made to reach the full beam energy and increase the extracted beam current density with a refurbished 1 MV epoxy insulator/bushing. Refurbishment had become necessary after the top two of the nine epoxy rings making up the insulator had been perforated and carbonised due to high voltage discharges. The best results achieved during the present campaign are 914 keV D − beams (58 mA, 1 s) with a D − current density of 30 A/m 2 and 600 keV D − beams (76 mA, 1 s) with a D − current density of 70 A/m 2 . These results are world records. The beam optics is largely as expected from the modelling with the Vector Fields OPERA 3D code.

The immunogenicity and protective efficacy of inactivated rotavirus vaccine administered intramuscularly with lipid adjuvants; MPL (monophosphoryl lipid A from Salmonella minnesota) or L3 (monooleate/lauric acid) was evaluated in an infant mouse model. Purified and formalin-inactivated rhesus rotavirus (I-RRV) combined with one of the adjuvants were administered to female balb/c mice at 0, 4 and 8 weeks. High serum IgG antibody titers developed in all vaccinated groups; I-RRV (GMT 45524+/-9819), I-RRV-MPL (GMT 190637+/-64250) and I-RRV-L3 (GMT 126266+/-27553). The formalin-inactivation procedure preserved neutralizing epitopes and elicited high neutralizing antibody titers; I-RRV (GMT 43053 S.E.M.+/-4189), I-RRV-MPL (GMT 66398 S.E.M.+/-20202) and I-RRV-L3 (GMT 60887 S.E.M.+/-10750). All offsprings to immunized dams were protected against clinical diarrhea upon oral challenge with RRV. The IgG1/IgG2a ratio was in all immunized groups approximately 1 suggesting development of a balanced Th1/Th2 response.

Urine separating sewerage systems have been promoted since urine contributes the major amounts of nitrogen (80%) and phosphorous (55%) to household wastewater, while only constituting 1% of the volume. To evaluate potential health risks from enteric viruses in stored urine used in agriculture, source-separated urine (pH 9) was challenged with rhesus rotavirus and Salmonella typhimurium phage 28B and their persistence followed over time. No significant inactivation of either rotavirus or the phage occurred at 5°C during 6 months of storage, while the mean T90 values at 20°C were estimated at 35 and 71 days for rotavirus and the phage, respectively. In pH controls (pH 7), the inactivation of rotavirus was similar to that in urine at both temperatures, whereas no decay of the phage occurred at either 5 or 20°C. Therefore, rotavirus inactivation appeared to be largely temperature-dependent, whereas there was an additional virucidal effect on the phage in urine at 20°C (pH 9). Hence, risks from enteric viruses are likely to be dictated by the proportion of faecal cross-contamination and the urine storage time and temperature. If stored at 20°C for at least 6 months, urine may be considered safe to use as a fertilizer for any crop.

The effect of neonatal brain infection of herpes simplex virus type 1 (HSV-1) on the development of sensorimotor function in the rat was investigated using an acoustic startle paradigm. Intracerebral inoculation of HSV-1 at day 2 after birth, but not at day 4, caused a significant delay in the development of prepulse inhibition of acoustic startle. A decrease in prepulse inhibition was shown at 37, 46 and 58 days of age in these rats compared to control rats. No evidence was obtained for other behavioural dysfunctions such as differences in sensorimotor reactivity, sensorimotor response habituation, spontaneous locomotor activity, rearing activity or stereotyped behaviour. Prepulse inhibition of acoustic startle is an accepted model of sensorimotor gating in the CNS, a function which has been shown diminished in schizophrenic persons. The present results suggest that early viral infections during a neurone-susceptible period may contribute to the development of this deficit.

In 1997, the JET device was operated for an extensive campaign with deuterium–tritium (D–T) plasmas (the DTE1 campaign). A comprehensive network of machine protection systems was necessary so that this experimental campaign could be executed safely without damage to the machine or release of activated material. This network had been developed over many years of JET deuterium plasma operation and therefore the modifications for D–T operation was not a significant problem. The DTE1 campaign was executed successfully and safely and the machine protection systems proved reliable and robust and, in the limited cases where they were required to act, functioned correctly. The machine protection systems at JET are described and their categorisation and development over time are summarised. The management, commissioning and operational experience during DTE1 are discussed and some examples of fault scenarios are described. The experience with protection systems at JET highlights the importance of correct design and philosophy decisions being taken at an early stage. It is shown that this experience will be invaluable data input to the safe operation of future large fusion machines.

Two small-scale double emulsion techniques for incorporation of formaldehyde-inactivated rotavirus particles (FRRV) into poly(lactide-co-glycolide) (PLG) microspheres were developed and optimised. The effects of high-speed homogenisation versus vortex mixing on the double emulsion stability, microsphere size, entrapment efficiency and in vitro release of FRRV in the second emulsification step were studied. A stable double emulsion was verified only when using vortex mixing in this step. Slow removal of the organic phase allowed measurement of the size of the emulsion droplets and subsequent prediction of the size of the resulting microspheres. Microspheres in the size range of 1-10 microm were prepared using both techniques. The homogenisation technique was sensitive to changes in the operating time, the emulsification energy and the volume of the outer aqueous phase, while the vortex technique was more robust. Rotavirus was released in vitro in a triphasic manner with both techniques. The more robust vortex technique was selected for preparation of PLG microspheres containing rotavirus for in vivo studies. After immunisation of mice with a single intramuscular injection, the PLG-FRRV microspheres elicited an IgG antibody response in serum detected by ELISA equally high as that elicited with FRRV alone. These results indicate that the antigenicity of FFRV was retained after incorporation into PLG microspheres using the vortex technique.

1. 1. The present experiments examined the effects of the nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), on some behavioural and biochemical effects of phencyclidine (PCP) and d-amphetamine (AMPH) in rats. Observation of behaviour was performed using a subjective scoring system. 2. 2. PCP (4 mg/kg) increased locomotor activity, rearing, sniffing, grooming and stereotyped behaviour, and decreased stillness. PCP also increased forepaw myoclonus, forepaw treading, head weaving, licking and chewing behaviour. Most of these behaviours were significantly suppressed by pretreatment with L-NAME (10 mg/kg). 3. 3. AMPH (1 mg/kg) exerted different effects on behaviour. It increased locomotor activity, rearing, sniffing, and stereotyped behaviour, and decreased stillness and grooming, but failed to affect the other behavioural items observed. Pretreatment with L-NAME did not counteract these effects. 4. 4. Ex vivo biochemical analysis indicated that PCP increased the tissue concentration of the dopamine (DA) metabolites, dihydroxyphenyl acetic acid (DOPAC) and homovanillic acid (HVA), in the ventral striatum (i.e., the nucleus accumbens and olfactory tubercles) and frontal cortex but not in the dorsal striatum. DA was not significantly affected in any of these regions. Furthermore, PCP increased the tissue concentration of the serotonin (5-HT) metabolite, 5-hydroxyindole acetic acid (5-HIAA), in a similar manner, while 5-HT was not affected. These biochemical effects were significantly counteracted by pretreatment with L-NAME. 5. 5. AMPH decreased tissue DOPAC concentration in the dorsal striatum, an effect which was not sensitive to pretreatment with L-NAME. However, the combined treatment with L-NAME and AMPH increased tissue DA concentration in all three regions investigated. 6. 6. The neurochemical and behavioural effects of PCP and AMPH were further investigated in an experimental model which allowed measurement of prepulse inhibition (PPI) of acoustic startle in parallel with in vivo microdialysis sampling of extracellular DA concentration in the brain of awake, freely moving animals. 7. 7. Both PCP (2 mg/kg) and AMPH (2 mg/kg) caused a significant decrease in PPI of similar magnitude and duration. These behavioural effects were accompanied by a significant increase in extracellular DA concentration in the nucleus accumbens (PCP: 213 ± 21% of basal concentration; AMPH: 563±117%). 8. 8. The decrease in PPI caused by PCP was blocked by pretreatment with L-NAME, but the change in DA concentration was not. Neither of these measures were significantly affected by L-NAME in AMPH-treated rats. 9. 9. In conclusion, this study shows that several behavioural and biochemical effects of PCP are prevented by pretreatment with the NOS inhibitor, L-NAME, while the effects of AMPH are less sensitive to this pretreatment. These observations emphasise the involvement of nitric oxide in the pharmacological effects of PCP.

To analyze sorting and compartmentalization of molecules in neuronal endomembranes, the distribution of endogenous proteins associated with the endoplasmic reticulum (ER), intermediate compartment, the Golgi apparatus in cultures of dorsal root ganglion (DRG), and hippocampal neurons was compared with that of newly synthesized ER-associated rotavirus proteins. The endogenous ER-retained immunoglobulin heavy chain binding protein, protein disulfide isomerase, and a peptide containing the KDEL amino acid sequence appeared in the soma and dendrites up to their first branching, but not in axons. However, two other endogenous ER-associated proteins, calreticulin and calnexin, occurred in axons as well as in the somatodendritic domains. The ER-associated rotavirus proteins, VP7 and NSP4, were widely distributed in cell bodies and dendrites. The former appeared also in axons and its localization partially overlapped with that of calreticulin and calnexin. One intermediate compartment protein, ER-Golgi-intermediate compartment-protein-53 (ERGIC-53), extended beyond the first division of the dendrites and did not, as the small guanosine 5'-triphosphate (GTP)-binding protein rab2, appear in axons. The location of rab2 to small vesicles was distinct from that of rotavirus VP7. Cis/medial Golgi cistern proteins were restricted to the cell bodies and proximal dendrites. This study emphasizes the marked heterogeneity in the targeting to axons and dendrites of proteins associated with ER and intermediate compartments. Therefore, the composition of axonal ER-retained molecules differs from that in the soma and this variation may reflect differences in functions between the ER compartments. Viral proteins are useful reporters for such heterogeneities and rotavirus VP7 may be a tool to reveal sorting signals for targeting of vesicular proteins to axons via a nonclassical Golgi-independent mechanism. Such signals may also determine viral targeting to different regions of the brain.

In this study we have used an expression system based on Semliki Forest virus (SFV) to study assembly and intracellular localization of certain capsid proteins of rotavirus in neurons and mammalian epithelial cells. The complete genes of vp2 (vp2A) and vp6 (vp6A) of group A rotavirus (SA-11) and gene 5 encoding vp6 (vp6C) of porcine group C rotavirus (strain Cowden/AmC-1) were inserted into an SFV expression replicon. Transfection of BHK-21 cells with in vitro -made SFV transcripts resulted in a high level of expression of the heterologous genes. Cotransfection with helper RNA encoding the SFV structural proteins, but lacking the genomic RNA packing signal, resulted in production of recombinant infectious virus. Immunological and biochemical analysis revealed that vp6 was expressed to high levels in primary neurons and mammalian epithelial cells and that vp6 was retained as an authentic homotrimer, stabilized by noncovalent interactions with native antigenic determinants. Thin section electron microscopy analysis revealed that vp6 alone assembled into viroplasm-like structures in the cytoplasm. While coexpression of vp2 and vp6 of group A rotavirus resulted in formation of single-shelled-like particles, no evidence of intracellular assembly was found, suggesting that other viral proteins are required for intracellular formation of single-shelled particles. A notable observation was that the vp6 proteins of group A and C rotaviruses showed different immunofluorescence patterns in BHK-21 cells; vp6C displayed an intense punctate immunofluorescence pattern, while vp6A was characterized by a pronounced filamentous staining in close vicinity to the cytoskeleton.

Rotavirus is one of very few viruses that utilizes the endoplasmic reticulum (ER) for maturation. The maturation process is unique not only because it involves translocation of subviral particles across the ER membrane, but also because mature virus is thought to be retained in the ER until cell lysis. Brefeldin A (BFA) is a compound that blocks protein export from the ER to the Golgi complex and causes disruption of the Golgi complex with relocation of resident Golgi proteins to the ER. We found that BFA had a pronounced effect on rotavirus assembly and oligosaccharide processing. Single-step growth experiments demonstrated that BFA reduced infectious progeny rotavirus yield by 99.9%. Immunohistochemical staining with monoclonal antibodies showed that all examined VP4, VP6, VP7, and NS28 epitopes remained unaffected by BFA. A novel observation from pulse–chase experiments was that BFA-treatment rapidly increased the molecular weight of the ER-associated VP7 followed by endo-β-N-acetylglucosaminidase H (endo H) resistance. A novel observation was also that thetrans-ER NS28 protein remained endo H sensitive through the course of BFA-treatment, but that the molecular weight varied during chase. Electron microscopy analysis revealed that BFA interfered in the transition from the intermediate enveloped particle to the mature double-shelled virus.

Schizophrenic patients are deficient in various neurologic measures reflecting information processing. One such measure in prepulse inhibition (PPI) of acoustic startle, in which schizophrenics display less inhibition than normal subjects. PPI is also diminished in rats treated with psychotomimetic drugs such as amphetamine and phencyclidine. PPI has been suggested as a model relevant for studying the pathophysiology of schizophrenia. We studied the effect of a variety of antipsychotics and putative antipsychotics and some key reference compounds on the acoustic startle response (ASR) and PPI. Some, but not all, antipsychotics tested (mainly selective dopamine D2 antagonists) enhanced PPI. Remoxipride and clozapine, both of which are antipsychotics, and the very potent and highly selective D2 antagonist, NCQ-298, did not. It is concluded that enhanced PPI in otherwise untreated rats does not reflect antipsychotic efficacy. We further noted that the effect on PPI was independent of the effect on ASR.

We have cloned and sequenced a carboxylesterase from rat liver and purified the corresponding protein from rat blood. The cDNA encodes the entire mature serum esterase protein. It is apparently identical to cDNAs cloned from rat liver by several groups (Long, R. M., Satoh, H., Martin, B. M., Kimura, S., Gonzales, F. J., and Pohl, L. R. (1988) Biochem. Biophys. Res. Commun. 156, 866-873; Takagi, Y., Morohashi, K.-i., Kawabata, S.-i., Go, M., and Omura, T. (1988) J. Biochem. (Tokyo) 104, 801-806; and Robbi, M., and Beaufay, H. (1992) Biochem. Biophys. Res. Commun. 183, 836-841). However, the identification of the protein encoded by this cDNA has not been previously reported. The COOH-terminal -TEHT sequence found in the rat serum carboxylesterase does not possess retention properties and is therefore responsible for its secretion and presence in the circulation. The rat serum carboxylesterase was purified to apparent homogeneity by affinity chromatography on immobilized antibody to rat liver microsomal acyl-CoA thioesterase followed by ion exchange chromatography. The purified protein, with a M(r) of approximately 70,000, was cleaved in situ in a polyacrylamide gel with trypsin, and two peptides were isolated and sequenced. Sequence analysis showed that both peptides were identical only to the corresponding deduced amino acid sequence of the cloned cDNA. Antibodies raised to the COOH-terminal amino acid sequence deduced from the cDNA cross-reacted with the purified rat serum carboxylesterase. Changes in serum esterase activity levels followed changes in protein mass in rat serum and changes in liver mRNA levels in response to various nutritional conditions while total liver esterase activity was essentially unchanged. The above experiments confirm the identity of the protein isolated from rat sera with the cDNA cloned from rat liver and suggest a function for the serum esterase in lipid metabolism.

A two-bottle, free-choice paradigm was used to investigate the influence of the serotonergic (5-HT) system on ethanol intake in genetically heterogeneous Wistar rats. Systemic administration of the 5-HT 1A agonist ipsapirone (1.25–5.0 mg/kg) caused a dose-dependent decrease in ethanol preference and intake, while the 5-HT 2 antagonist ritanserin (1.25–5.0 mg/kg) and the 5-HT 3 antagonists ondansetron (0.01–1.0 mg/kg) and granisetron (0.5–1.0 mg/kg) failed to alter ethanol consumption. The effect of ipsapirone treatment on ethanol intake was more pronounced in high-preferring animals than in low-preferring. A closer look at the microstructure of the rat's drinking behaviour by means of a microcomputer-controlled data acquisition system showed that ipsapirone treatment caused a significant decrease in the number of licks recorded at the ethanol-containing bottle and a decrease in the time spent at this bottle. Furthermore, ipsapirone treatment caused a significant increase in the number of breaks in licking behaviour recorded at this bottle. The drinking behaviour at the water-containing bottle was not affected by the ipsapirone treatment. Neither was the rat's eating behaviour altered by this treatment. These findings support the hypothesis that the 5-HT system is involved in the regulation of ethanol intake, with special emphasis on the involvement of the 5-HT 1A receptor subtype, and may indicate that central reward-mediating mechanisms are influenced.

In vivo voltammetry at electrochemically pretreated carbon fibre electrodes was used to investigate the effect of ageing on extracellular ascorbate (AA) concentration in the rat brain. Recordings from the nucleus accumbens in 3-, 6- and 18-month-old Sprague-Dawley rats revealed an age-related decrease in basal extracellular AA concentration. The mean AA current measured in 18-month-old rats was less than 10% of the current measured in 3-month-old rats. Systemic administration of ethanol (1.0 g/kg, i.p.) caused an increase in the AA signal measured in this area in all 3 age groups tested. However, the effect on AA was significantly less pronounced in 18-month-old rats. Further analysis of the AA signal revealed a gradual increase in AA release during terminal anoxia. Also in this case the effect on AA was significantly less pronounced in 18-month-old rats. This difference was also observed in the caudate putamen, another dopamine (DA) rich area in the brain. No significant difference in AA release was observed in the frontal cortex where the DA concentration is low. The increase in AA was followed by a pronounced increase in extracellular DA in the nucleus accumbens and caudate putamen. This release of DA was accompanied by a prompt reversal of the AA signal possibly explained by a DA-dependent autoxidation of AA. These results suggest a role for brain AA in the process of ageing.

An in vivo voltammetry technique was used to monitor the extracellular ascorbate (AA) concentration in the nucleus accumbens and striatum of unanesthetized, freely moving rats. A single injection of ethanol, 1.0 g/kg intraperitoneally (IP), induced a significant increase in extracellular AA concentration in both the nucleus accumbens and striatum. This effect was dose dependent within a dose range from 0.5–2.0 g/kg. 4-Methylpyrazole (50 mg/kg, IP), which inhibits alcoholdehydrogenase, could not prevent the increase in AA concentration, evoked by ethanol. Furthermore, systemic administration of acetaldehyde (20 mg/kg, IP), the main metabolite of ethanol, did not have any effect on the level of AA in the nucleus accumbens or striatum. These results show that ethanol can alter the brain extracellular AA levels and that this effect seems to be attributed to ethanol itself and not to acetaldehyde. Consequently, these results indicate that a role for AA in the action of ethanol in the brain should be considered.

In vivo voltammetry at electrochemically pretreated carbon fibre electrodes was used to investigate the effect of intracerebroventricular (i.c.v.) administration of N-methyl-D-aspartic acid (NMDA) on neuronal activity in rat nucleus accumbens. Infusion of a low dose of NMDA (1 nmol) was followed a few minutes later by rapid changes in both Peak 1 and Peak 2 heights indicating large but short-lived increases in the extracellular concentrations of ascorbate and catecholamines, respectively. These responses did not seem to be dependent on the dose infused since infusion of NMDA for a longer time period neither changed the amplitude nor the time-course of these effects. The increase in Peak 2 height was resistant to pargyline pretreatment indicating that this response mainly reflected the release of dopamine. The administration of NMDA was followed by behavioural activation in the animals but not convulsions. Co-administration of the competitive NMDA receptor antagonist, CPP (1 nmol), completely blocked these effects while the acetylcholine receptor antagonist, atropine (1.5 nmol), and the GABA receptor antagonist, picrotoxin (1 nmol), failed in this respect. The phenomenon spreading depression is discussed as a possible explanation of these results.

Spontaneously hypertensive rats of the Okamoto strain (SHR) were compared with normotensive rats of the Wistar-Kyoto strain (WKY) on the acoustic startle response in rats prepared for simultaneous blood pressure recordings. Blood pressure was continuously recorded by means of an indwelling cannula in the caudal tail artery. The presentation of the startle stimulus caused a blood pressure response in both strains consisting of an initial increase in blood pressure followed by a decrease and after that a longer lasting, but less pronounced second increase in pressure. The startle-elicited increase in blood pressure was significantly elevated in SHRs and at the same time the acoustic startle response was depressed as compared to WKY rats. These data indicate a dissociation between cardiovascular and behavioral reactivity in the SHR.

When subjected to capillary gas chromatography, picolinyl ester derivatives of fatty acids were shown to have as good chromatographic properties as the corresponding methyl esters. By using a capillary column of medium polarity (Supelcowax 10), excellent resolution with respect to chain length, degree of unsaturation and positional isomers was obtained without any serious problems with a disturbed background due to column bleed in the mass spectrometric interpretation of diagnostic ions. These features permitted a simple one-step procedure to be carried out for the characterization of fatty acids with respect to molecular weight, number of double bonds and positional isomers. The usefulness of the technique for the identification of the fatty acids in borage seed oil (Borago officinalis) was demonstrated. In addition to γ-linolenic acid, the most important fatty acid in borage seed oil from a commercial standpoint, a further fourteen different fatty acids could be positively identified.

Tail pinch in the rat gives rise to a well characterised pattern of behaviour which includes gnawing, licking and eating. We have used both in vivo voltammetry and microdialysis to monitor neurochemical changes which accompany the behavioural response to a 5-min tail pinch. Tail pinch resulted in a increase of extracellular 5-hydroxytryptamine and a smaller and more delayed increase of 5-hydroxyindole acetic acid in the hippocampus. In the striatum there was a rise of both extracellular dopamine and ascorbate. With a recently developed constant potential voltammetric technique we can continuously monitor changes in extracellular ascorbate. Using this technique we found a very rapid rise in ascorbate current during a 5-min tail pinch; the current began to decline as soon as the clip was removed. The high time resolution of the technique also allowed us to record similar ascorbate changes during a 0.5-s tail pinch.

The (+) and (-) isomers of 3-(3-hydroxyphenyl)-N-propylpiperidine (3-PPP) (2–32 mg/kg) were tested for their effects on the acoustic startle response in the rat and these effects were compared with those of apomorphine and haloperidol. Both startle amplitude and startle latency were recorded. (+)-3-PPP produced a dose-dependent prolongation of startle latency. No other significant effects of the 3-PPP isomers were observed. Apomorphine (0.75–3 mg/kg) produced a dose-dependent increase in startle amplitude concurrent with a dose-dependent prolongation of startle latency. Both these effects were blocked by haloperidol. Haloperidol by itself produced a significant decrease in startle amplitude at the highest dose used (1.6 mg/kg). These and other data suggest that activation of both dopamine D-1 and dopamine D-2 receptors is essential for the stimulatory effects of dopamine receptor agonists on the acoustic startle response in the rat.