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BACKGROUND & AIMS: Hepatitis B virus (HBV) contains three viral surface proteins, large, middle and small hepatitis B surface protein (LHBs, MHBs, SHBs). Proportions of LHBs and MHBs are lower in patients with inactive versus active chronic infection. Interferon alfa may convert HBeAg-positive chronic hepatitis B (CHB) to an inactive carrier state, but prediction of sustained response is unsatisfactory. The aim of this study was to test the hypothesis that quantification of MHBs and LHBs may allow for a better prognosis of therapeutic response than total hepatitis B surface antigen (HBsAg) concentration. METHODS: HBs proteins were measured before and during peginterferon alfa-2a therapy in serum from 127 Asian patients with HBeAg-positive CHB. Sustained response was defined as hepatitis B e antigen (HBeAg) seroconversion 24 weeks post-treatment. RESULTS: Mean total HBs levels were significantly lower in responders versus nonresponders at all time points (P0.70). CONCLUSIONS: HBs proteins levels differ by HBV genotype. However, quantification of HBs proteins has no advantage over the already established HBsAg assays to predict response to peginterferon alfa-2a therapy in HBeAg-positive patients.

In human electrophysiology research, the high gamma part of the power spectrum (~>60 Hz) is a relatively new area of investigation. Despite a low signal-to-noise ratio, evidence exists that it contains significant information about activity in local cortical networks. Here, using magnetoencephalography (MEG), we found high gamma activity when comparing data from an n-back working memory task to resting data in a large sample of normal volunteers. Initial analysis of power spectra from 0-back, 2-back, and rest trials showed three frequency bands exhibiting task-related differences: alpha, beta, and high gamma. Unlike alpha and beta, the high gamma spectrum was broad, without a peak at a single frequency. In addition, power in high gamma was highest for the 2-back and lowest during rest, while the opposite pattern occurred in the other bands. Beamformer source localization of each of the three frequency bands revealed a distinct set of sources for high gamma. These included several regions of prefrontal cortex that exhibited greater power when both n-back conditions were compared to rest. A subset of these regions had more power when the 2-back was compared to 0-back, which indicates a role in working memory performance. Our results show that high gamma will be important for understanding cortical processing during cognitive and other tasks. Furthermore, data from human intracortical recordings suggest that high gamma is the aggregate of spiking in local cortical networks, which implies that MEG could serve to bridge experimental modalities by noninvasively observing task-related modulation of spiking rates.

Multipass friction-stir processing was employed to uniformly disperse multiwalled carbon nanotubes (MW-CNTs) within an Al-Mg alloy metal matrix. Decomposition of MW-CNTs occurs in situ as a result of solid-state chemical reactions, forming fullerene (C60) and aluminium carbide (Al4 C3 ) phases during reactive high temperature severe plastic processing. The effects of this decomposition on the microstructural features, dynamic restoration mechanisms and crystallographic microtextural developments are studied for the first time by using electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) analysis. The formation of an equiaxed grain structure with an average size of ∼1.5 μm occurs within the stirred zone (SZ) under the influence of inclusions which hinder grain boundary migration via Zener-Smith pinning mechanisms during the discontinuous dynamic recrystallisation (DDRX). Formation of two strong Cubic and Brass microtextural components in the heat affected zone (HAZ) and thermomechanical affected zone (TMAZ) was noted as compared to the completely random and Cube components found in the base and SZ regions, respectively. The microstructural modification led to hardening and tensile strength improvement for the processed nanocomposite by ∼55% and 110%, respectively with respect to the annealed Al-Mg base alloy.

BACKGROUND: Previous studies showed controversial results for the influence of pregnancy-related and perinatal factors on subsequent respiratory and atopic diseases in children. The aim of this study was to assess the association between perinatal variables and the prevalence of asthma, bronchial hyperreactivity (BHR), flexural eczema (FE), allergic rhinitis, and sensitization in childhood and early adulthood. METHODS: The studied population was first examined in Munich and Dresden in 1995/1996 at age 9-11 years. Participants were followed until age 19-24 years using questionnaires and clinical examinations. Associations between perinatal data and subsequent atopic diseases were examined using logistic regression analyses adjusting for potential confounders. RESULTS: Cesarean section was statistically significantly associated with BHR in early adulthood (odds ratio 4.8 [95% confidence interval 1.5-15.2]), while assisted birth was associated with presence of asthma symptoms in childhood (2.2 [1.2-3.9]), FE symptoms (2.2 [1.2-4.3]) and doctor's diagnosis of atopic dermatitis (1.9 [1.0-3.4]) in childhood, and sensitization in early adulthood (2.2 [1.1-4.3]). Lower birth length (1.9 [1.1-3.2]), lower birthweight (0.5 [0.3-0.9]), and higher birthweight (0.6 [0.4-1.0]) were predictive of sensitization in early adulthood compared to average birth length and birthweight, respectively. None of the other perinatal factors showed statistically significant associations with the outcomes. CONCLUSIONS: Our results indicate that children who are born by cesarean section and especially by assisted birth, might be at greater risk for developing asthma, FE, and sensitization and should hence be monitored. Prenatal maternal stress might partly explain these associations, which should be further investigated.

In September 2010, an outbreak of acute hepatitis B virus (HBV) infections in a nursing home was notified to public health authorities in Northern Germany. To identify the route of transmission and prevent further cases a retrospective cohort study was conducted. Blood samples of residents were tested for serologic markers of HBV infection and HBV subgenotypes and sequences were analyzed. Outbreak-related cases were defined as residents of the nursing home with detection of hepatitis B surface antigen (HBsAg) and the HBV DNA sequence of the outbreak strain in 2010. Information on possible risk factors as patient care, invasive diagnostic, and therapeutical procedures was collected using a standardized questionnaire. Risk ratios (RR) and 95% confidence intervals (CI) were estimated with exact Poisson regression and binomial regression. Sixty-four residents were included in the study, 5 of them were outbreak-related cases, 12 had a past HBV infection. The outbreak strain belonged to HBV genotype D2 (HBsAg subtype ayw3, Ala118) which is not prevalent in Germany but in Eastern Europe. All cases (median age 81) were female, had diabetes, blood glucose monitoring, and chiropody. In multivariable analysis only blood glucose monitoring was associated with HBV infection (RR = 22, 95%CI 3.0-∞). Blood glucose monitoring was reported to be done by nursing home staff with patient-based reusable lancet devices. In nursing home settings the use of single use lancets for blood glucose monitoring is recommended strongly to prevent transmission. National guidelines on the handling of point-of-care devices and reusable equipment in long-term care facilities should be developed.

Nonprofit organizations are as susceptible to crisis as any organization as exemplified by Livestrong's attempts to outlive Lance Armstrong's downfall and Planned Parenthood (PP) overcoming Susan G. Komen for the Cure's (SGK) policy to defund organizations under investigation. The public battles held on social media during crises such as these have forced organizations onto new battlegrounds. Supporters for each of these nonprofits proudly shared their thoughts via tweets (e.g. #IstandwithPP) and status updates, as the organizations raced to control the situation. PP had tweeted SGK's policy change creating a bevy of support while sending SGK into a reversal that is still costing racers. Surveys were distributed following Armstrong's performance-enhancing drug use confession and SGK's funding policy announcement to determine attitudes toward giving after organizational crisis. The Theory of Planned Behavior (TPB) was used to assess the strength of attitude, social norms, and perceived behavioral control on the intent to donate to these organizations. The use of TPB expands nonprofit marketing horizons by helping better understand stakeholder intentions and their causes. On the basis of the findings, best practices for nonprofits handling crisis were identified. In particular, organizations need to know their target audiences, know what will make supporters remain, look at crises as opportunities for renewal, be honest, and apologize when appropriate. Copyright © 2014 John Wiley & Sons, Ltd.

Nuclei of Xenopus laevis oocytes grow 100 000-fold larger in volume than a typical somatic nucleus and require an unusual intranuclear F-actin scaffold for mechanical stability. We now developed a method for mapping F-actin interactomes and identified a comprehensive set of F-actin binders from the oocyte nuclei. Unexpectedly, the most prominent interactor was a novel kinesin termed NabKin (Nuclear and meiotic actin-bundling Kinesin). NabKin not only binds microtubules but also F-actin structures, such as the intranuclear actin bundles in prophase and the contractile actomyosin ring during cytokinesis. The interaction between NabKin and F-actin is negatively regulated by Importin-β and is responsive to spatial information provided by RanGTP. Disconnecting NabKin from F-actin during meiosis caused cytokinesis failure and egg polyploidy. We also found actin-bundling activity in Nabkin's somatic paralogue KIF14, which was previously shown to be essential for somatic cell division. Our data are consistent with the notion that NabKin/KIF14 directly link microtubules with F-actin and that such link is essential for cytokinesis., The presence and role of actin filaments in cell nuclei remains incompletely understood. A proteomics approach now reveals a highly distinct set of F-actin-binding proteins in the nucleus, including a novel kinesin family member.

Mass spectrometry (MS) is an important analytical technique for the detection and identification of small compounds. The main bottleneck in the interpretation of metabolite profiling or screening experiments is the identification of unknown compounds from tandem mass spectra. Spectral libraries for tandem MS, such as MassBank or NIST, contain reference spectra for many compounds, but their limited chemical coverage reduces the chance for a correct and reliable identification of unknown spectra outside the database domain. On the other hand, compound databases like PubChem or ChemSpider have a much larger coverage of the chemical space, but they cannot be queried with spectral information directly. Recently, computational mass spectrometry methods and in silico fragmentation prediction allow users to search such databases of chemical structures. We present a new strategy called MetFusion to combine identification results from several resources, in particular, from the in silico fragmenter MetFrag with the spectral library MassBank to improve compound identification. We evaluate the performance on a set of 1062 spectra and achieve an improved ranking of the correct compound from rank 28 using MetFrag alone, to rank 7 with MetFusion, even if the correct compound and similar compounds are absent from the spectral library. On the basis of the evaluation, we extrapolate the performance of MetFusion to the KEGG compound database.

Background Occult hepatitis B virus (HBV) infection (OBI) is identified in 1:1000 to 1:50,000 European blood donations. This study intended to determine the infectivity of blood products from OBI donors. Study Design and Methods Recipients of previous donations from OBI donors were investigated through lookback (systematic retrieval of recipients) or traceback (triggered by clinical cases). Serologic and genomic studies were undertaken on consenting donors and recipients. Multiple variables potentially affecting infectivity were examined. Results A total of 45 of 105 (42.9%) donor-recipients pairs carried antibodies to HBV core (anti-HBc) as evidence of previous HBV infection. Subtracting 15% of anti-HBc population background, the adjusted transmission rate was 28%. Anti-HBc prevalence increased to 28 of 44 (63.8%) in unvaccinated recipients receiving anti-HBs–negative OBI blood products. In contrast, four of 26 (15.4%) recipients of anti-HBs–positive products were anti-HBc positive. Transmission with anti-HBs–negative products depended on volume of plasma transfused (85%-100% with 200 mL of fresh frozen plasma [FFP], 51% with 50 mL in platelet concentrates [PCs], and 24% with 20 mL in red blood cells [RBCs], p

Most hepatitis B virus (HBV) vaccines consist of viral small surface (S) protein subtype adw2 expressed in yeast cells. In spite of good efficacy, HBV-genotype and subtype differences, escape mutants and insufficient Th1 activation remain potential problems. To address these problems, we generated recombinant Semliki Forest virus (rSFV) vectors encoding S protein, subtype adw2 or ayw2, or a fragment of the large surface protein, amino acids 1-48 of the pre-S1 domain, fused to S (pre-S1.1-48/S). The antigen loop in S protein and the selected pre-S1 sequences are known targets of neutralizing antibodies. BALB/c mice were immunized intravenously with 10(7) rSFV particles and 10(8) rSFV particles 3 weeks later. Antibodies induced by rSFV encoding S proteins reacted preferentially with subtype determinants of yeast-derived S antigen but equally well with patient-derived S antigen. Immunization with rSFV encoding pre-S1.1-48/S resulted in formation of pre-S1- and S-specific immunoglobulin G (IgG), while immunization with the isogenic mutant without S start codon induced pre-S1 antibodies only. Neutralizing antibodies were determined by mixing with plasma-derived HBV/ayw2 and subsequent inoculation of susceptible primary hepatocyte cultures from Tupaia belangeri. S/adw2 antisera neutralized HBV/ayw2 as effectively as antisera raised with S/ayw2. The pre-S1 antibodies also completely neutralized HBV infectivity. The IgG1/IgG2a ratios ranged from 0.28 to 0.88 in the four immunized groups and were lowest for the pre-S1.1-48/S vector, indicating the strongest Th1 response. This vector type may induce subtype-independent and S-escape-resistant neutralizing antibodies against HBV.

BACKGROUND: Fresh-frozen plasma (FFP) may contain antibodies to hepatitis B surface antigen (HBsAg, anti-HBs). These anti-HBs may lead to a misinterpretation of the actual hepatitis B immune status. Furthermore, they may not only confer protection against hepatitis B virus (HBV), but may also favor the selection of HBsAg mutants. CASE REPORT: We report a case of de novo HBV infection in a HBV-naive recipient with alcoholic liver disease, who received a liver from a donor with antibodies to hepatitis B core antigen (HBcAg, anti-HBc) and anti-HBs. RESULTS: A lookback investigation revealed the following: 1) Due to anti-HBs passively acquired through FFP, the recipient was considered immune to HBV and did not receive anti-HBV prophylaxis. 2) Within 1 year after transplantation he developed hepatitis B in absence of any elevated liver enzymes after the anti-HBs by FFP declined. 3) Despite an infection with HBV-containing wild-type HBcAg, the patient did not seroconvert to anti-HBc positivity. 4) The replicating HBV encoded two HBsAg mutations, first sQ129R and 4 months later sP127S. They map to the highly conserved "alpha" determinant of the HBsAg loop. CONCLUSION: 1) Passive transfer of anti-HBs from FFP led to an erroneous pretransplant diagnosis of HBV immunity when the patient was in fact HBV-naive. 2) HBsAg mutations might have been selected in escape from donor's actively produced anti-HBs and the recipient's anti-HBs by FFP might have favored this selection. 3) It is doubtful whether hepatitis B immunoglobulin could have prevented the reactivation. 4) Antiviral prophylaxis would have been crucial.

Summary. Seroconversion from hepatitis B surface antigen (HBsAg) to antibodies against HBsAg (anti-HBs) usually indicates resolution of hepatitis B virus (HBV) infection. Here, two HBV-infected patients with seroconversion to anti-HBs were found to be persistently positive for HBeAg and HBV DNA. Immunohistology of liver biopsies confirmed the expression of HBV proteins in the liver of one patient. The neutralizing ability of anti-HBs in patient sera was demonstrated by blocking HBV infection of primary tupaia hepatocytes. Analysis of the HBsAg-encoding region of HBV isolates from patients indicated the coexistence of heterogeneous HBV genomes in patients. The majority of recombinant variant HBsAg was reactive in HBsAg assays and was able to bind to anti-HBs. Circulating immune complexes (CIC) of HBsAg in patient sera could be detected by polyethylene glycol precipitation and trypsin digestion. Thus, neutralizing anti-HBs may appear in chronic HBV carriers for long periods but does not necessarily lead to complete viral clearance.

A. Pruss, G. Caspari, D.H. Kruger, J. Blumel, C.M. Nubling, L. Gurtler, W.H. Gerlich. Tissue donation and virus safety: more nucleic acid amplification testing is needed. Transpl Infect Dis 2010: 12: 375–386. All rights reserved Abstract: In tissue and organ transplantation, it is of great importance to avoid the transmission of blood-borne viruses to the recipient. While serologic testing for anti-human immunodeficiency virus (HIV)-1 and -2, anti-hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg), anti-hepatitis B core antigen (HBc), and Treponema pallidum infection is mandatory, there is until now in most countries no explicit demand for nucleic acid amplification testing (NAT) to detect HIV, hepatitis B virus (HBV), and HCV infection. After a review of reports in the literature on viral transmission events, tissue-specific issues, and manufacturing and inactivation procedures, we evaluated the significance of HIV, HCV, and HBV detection using NAT in donors of various types of tissues and compared our results with the experiences of blood banking organizations. There is a significant risk of HIV, HCV, and HBV transmission by musculoskeletal tissues because of their high blood content and the high donor–recipient ratio. If no effective virus inactivation procedure for musculoskeletal tissue is applied, donors should be screened using NAT for HIV, HCV, and HBV. Serologically screened cardiovascular tissue carries a very low risk of HIV, HCV, or HBV transmission. Nevertheless, because effective virus inactivation is impossible (retention of tissue morphology) and the donor–recipient ratio may be as high as 1:10, we concluded that NAT should be performed for HIV, HCV, and HBV as an additional safety measure. Although cornea allografts carry the lowest risk of transmitting HIV, HCV, and HBV owing to corneal physiology, morphology, and the epidemiology of corneal diseases, NAT for HCV should still be performed. If the NAT screening of a donor for HIV, HCV, and HBV is negative, quarantine storage of the donor tissue seems dispensable. In view of numerous synergistic effects with transfusion medicine, it would be advantageous for tissue banks to cooperate with blood bank laboratories in performing virological tests.

BACKGROUND AND OBJECTIVES The aim of this study was to replace the 1st World Health Organization International Standard for hepatitis B virus DNA for nucleic acid amplification technique (NAT)-based assays (code 97/746) with a new International Standard. Two lyophilized preparations freeze dried from the same bulk were evaluated in the original collaborative study (coded 97/746 and 97/750, and termed AA and BB, respectively, in the original study). This present study re-evaluates these two preparations in terms of potency and real-time stability. MATERIALS AND METHODS The 1(st) International Standard (97/746) and the second lyophilized preparation (97/750) were coded Samples 1 and 2, respectively, in the present study. The samples were distributed to six laboratories and assayed on four separate occasions. Accelerated thermal degradation samples of the two preparations were examined after long-term storage at 4 degrees C and 20 degrees C for more than 51 months. RESULTS Data were returned from a total of nine different NAT-based assays, five in qualitative format and four in quantitative format. The results of this study confirm the results of the original collaborative study, with no significant differences being found in estimated international units (IU)/ml or polymerase chain reaction-detectable units/ml for the 1(st) International Standard (Sample 1 in this study) and the proposed replacement preparation, Sample 2 (97/750). Real-time and accelerated degradation studies indicate that both samples are very stable. Storage of both preparations at 20 degrees C for more than 51 months resulted in no detectable degradation. CONCLUSIONS On the basis of the data presented in this collaborative study, Sample 2 (code 97/750) was established as the 2nd International Standard for hepatitis B virus DNA for NAT-based assays with a potency of 10(6) IU/ml (500,000 IU/vial).

Five blood donors with occult persistent and one donor with an early window phase HBV infection were identified. They were negative in regular HBsAg screening and had low levels of HBV DNA that were probably not detectable by current mini-pool nucleic acid amplification testing. In four donors several mutations were found located in the HBs antigen loop. In three donors the mutations were predominantly outside the "a" determinant; one donor had a wild type HBsAg sequence. Fifty-five recipients of donations from the persistently infected donors could be tested for previous or ongoing HBV infection and of them 53% (29/55) were anti-HBc positive. Based on the prevalence of anti-HBc in Germany (7%), it was assumed that four of those recipients had already been positive before transfusion. In 22 cases, it was assumed that they acquired infection by the donations, but the infection remained asymptomatic and was resolved. In three cases transmission was proven by the time course of the acute infection and sequence identity The resulting infection was fatal and associated with immunological disorders at the time of transmission: in one case sepsis and in the othertwo cases immunosuppression. In a further asymptomatic case of proven transmission from the early window phase donation passively administered anti-HBs could not prevent spread of wildtype HBV but antiviral treatment lead to resolution. Surprisingly the typical acute hepatitis B was not observed in a single one of the 26 cases of assumed or proven transmission.

The kinetics of hepatitis B virus (HBV) and its surface antigen (HBsAg) during acute hepatitis has not yet been studied accurately in a representative number of patients. The influence of coinfecting hepatitis viruses during the acute phase of infection is not known. Three to four serum samples from 21 patients with acute HBV monoinfection and 27 with coinfection were taken at intervals of 6-10 days and analyzed for the number of HBV genome equivalents (ge) by real time polymerase chain reaction (PCR) and for HBsAg quantity using Laurell electrophoresis. Log HBV ge/ml decreased during the follow-up from 6.8 +/- 1.1 to 5.1 +/- 1.0 to 4.2 +/- 0.8 to 3.3 +/- 1.1 (mean +/- SD). The half-life times of HBV ge increased from 1.6 days at the beginning to 4 days at the end. HBsAg decreased much slower: from 38 to 23 to 12 to 3.8 microg/ml. Half-life time was around 8 days at the beginning and 5.7 days at the end, but 11 patients showed a rapid elimination of HBsAg and HBV DNA. Hepatitis C virus (HCV) coinfection did not change the kinetics of HBV ge and HBsAg significantly. A moderate but significant suppression of HBV ge levels was observed in hepatitis D virus (HDV) coinfected patients. HBsAg levels were, however, enhanced in this cohort. In conclusion, the data suggest that expression and elimination of HBV is in most patients with acute hepatitis B not altered by coinfecting hepatitis viruses. The initial decrease of HBV ge and HBsAg in serum appears to be caused by decay or non-specific removal in the absence of replacement.

Background and objectives Twenty-two laboratories from nine countries participated in an international collaborative study to establish a World Health Organization (WHO) international standard for hepatitis B virus (HBV) DNA nucleic acid amplification techniques (NAT). Materials and methods Three samples, AA, BB (both of which were lyophilized) and CC (which was a liquid preparation), were analysed using several different NAT assays. The mean HBV DNA content of each sample was determined from the study. Results Despite the range of assays (commercial and in-house) used by participants, there was good agreement among the overall mean ‘equivalents’/ml obtained by the different assays, except for one laboratory (laboratory 4). The variation in estimates of log10‘equivalents’/ml was 1·75–1·25 for the three samples if results from laboratory 4 were excluded. The mean log10‘equivalents’/ml for all laboratories were 6·42 for sample AA, 6·30 for sample BB and 5·03 for sample CC (exclusion of results from laboratory 4 made little difference). The difference in titres between the two lyophilized samples (AA and BB) was not statistically significant but the titre of the frozen sample (CC) was significantly lower. Material AA (code 97/746) was accepted as the first WHO international standard for HBV DNA NAT assays and assigned a potency of 106 international units (IU)/ml. Conclusions The titres (genome equivalents/ml) of three HBV preparations were determined by several laboratories using different NAT assays. This study enabled the establishment of an international standard, 97/746, for HBV DNA NAT assays.

In areas with low hepatitis B virus (HBV) endemicity such as most parts of Europe and the United States “anti-HBc alone” is found in 10–20% of all individuals with HBV markers, i.e., 1–4% of the population. In about 10% of these individuals HBV DNA is detected by PCR, the proportions varying greatly depending on the population studied, being highest in individuals coinfected with hepatitis C virus (HCV) (above 35%) and HIV (above 85%). A small proportion of individuals with “anti-HBc alone” are in the window phase of an HBV infection or in a stage of late HBV immunity. For the large proportion of these individuals this is not the case and they are thought to have an unresolved HBV-infection or a chronic infection in a late or “low grade” productive state. Currently, limited studies have been performed concerning the clinical aspects of individuals with “anti-HBc alone” and suspected chronic HBV infection. The majority of these individuals seem to be healthy. Some chronic carriers with “anti-HBc alone,” however, do present signs of chronic hepatitis. Individuals with “anti-HBc alone” are potentially infectious. This is exemplified by a few case reports of HBV transmission to sexual contacts, perinatal transmission between mother and newborns and in blood recipients. Recommendations are given in relation to both the diagnostic and therapeutic procedures in the individuals with “anti-HBc alone” and in the blood banking and transplantation services. J. Med. Virol. 62:450–455, 2000. © 2000 Wiley-Liss, Inc.

Since the beginning of blood transfusions concomitant transmission of viral hepatitis has been a frequent and serious side-effect. A first measure to reduce the frequency of transmission was the screening of blood donors for elevated levels of liver enzymes in the blood, which was introduced in Germany in the 1960s, but not in most other countries. After the discovery of hepatitis B virus (HBV), donors in all countries have been screened since the 1970s for its surface antigen (HBsAg). When it was realized that there was at least one other type of virus that was even more frequently transmitted, screening for liver enzymes and HBV antibodies (anti-HBc) was introduced as a surrogate marker in most, but not all, countries in the 1980s. Furthermore, donors at risk for parenterally transmitted viruses were excluded. The discovery of the hepatitis C virus (HCV) genome and the development of sensitive anti-HCV assays has meant that reliable detection of persistently infected HCV carriers has been possible since 1991. Recently infected donors, however, are infectious for several weeks or months before anti-HCV is detectable. Therefore, starting in April 1999 all donations in Germany have to be tested, by nucleic acid amplification tests, for the presence of HCV RNA, although preliminary experience shows that such recent HCV infections are very rare. Newly detected viruses, named GBV-C or HGV and TTV, have been detected in patients with non-A-E post-transfusion hepatitis, but their association with the disease seems to be coincidental. These viruses cause persistent viraemia and are quite prevalent world-wide, but do not cause any known disease. At present, transfusion-transmitted hepatitis has been virtually eliminated, and any improvement in safety will be very small and will require huge costs.

Different approaches for studying low-energy (meV) reactive ion-molecule collisions in molecular beams are presented. In particular, differences in the photoionization (REsonant Multi-Photon Ionization / REMPI, Pulsed Field Ionization / PFI) experiments using single molecular beams vs. merged and crossed beams are discussed. We address the question of the proper determination of cross sections and rate constants in single beam experiments and the factors that influence the width of the collision energy distributions. We identify space charge effects as the dominant contribution under our experimental conditions. Problems pertinent to state-selected primary ion preparation with narrow energy distributions are highlighted. In light of the detailed data analysis, the derived relations are applied to the four-center reaction H2+ + H2 H3+ + H, which was studied in single and merged molecular beam experiments. We present merged beam data for the absolute reaction cross section for primary ions created in a storage ion source in the energy range from 5 meV up to 5 eV and relative state-selected cross sections for different vibrational and rotational ion states (v = 0,1; j = 0–4) generated by (3+1) REMPI for a mean collision energy of about 10 meV.

Light steel-frame building systems are becoming more prevalent in commercial, industrial and residential construction in New Zealand. Tested fire resistance ratings are generally available for non-load-bearing systems, but not for load-bearing applications. This study investigates the performance of load-bearing light steel-frame systems exposed to fire. Methods are presented for calculating the reduction of steel strength and stiffness at elevated temperatures, and for predicting the deflections resulting from temperature gradients and P-Δ effects. Heat transfer modelling by computer is used to predict steel framing temperatures for systems exposed to the standard ISO 834 time–temperature curve and real fires. Three full-scale furnace tests were carried out to evaluate analytical predictions. A design procedure is proposed.

The synthesis and characterization of seven tailor-made highly fluorous porphyrin derivatives are described, as large perfluoroalkyl-functionalized organic molecules are the most complex objects for which the quantum wave nature has been observed so far. We have found, in particular, that tetrakis(pentafluorophenyl)porphyrin is a suitable starting point for a modular synthesis that is geared towards porphyrin derivatives with many peripheral fluorous chains. This allows us to tailor and optimize the sublimation features of these compounds for molecule interferometry. We have analyzed the evaporation process of one member of the series by determining the enthalpy of evaporation, as the creation of a sufficiently intense, slow molecular beam is crucial for quantum interference experiments. We present the quantum fringe pattern of a second member of the series, which we could obtain in a Kapitza?Dirac?Talbot?Lau interferometer.