Influence of two different solid-liquid separation processes on the settling characteristics of swine effluent.

ABSTRACT: Solid-liquid separation (SLS) in swine manure treatment is an important step due to a substantial amount of organic and inorganic solids that can be removed from liquid wastewater. The aim of this study was to evaluate the efficiency of two mechanical separation processes (screw press and rotary screen) followed by settling and to analyze the composition of liquid fractions. In this sense, total solids (TS), volatile solids (VS), fixed solids (FS), total phosphorous (TP), total Kjeldahl nitrogen (TKN) and total organic carbon (TOC) were analyzed. By combining mechanical separation with settling, the average of TS, VS and FS removal was 75%, 80% and 69%, respectively. Phosphorus removal reached 86%, and TKN achieved a reduction up to 45%. There was no statistical difference among the results obtained using SLS by screw press and rotary screen. It was possible to conclude that SLS process with mechanical devices, followed by settling, generates a suitable effluent to be used on nitrification and denitrification process, producing an effluent with a C/N ratio of 2.6, and the solid fraction is useful to anaerobic digestion

Study of nitrogen consumption by nitrification process.

ABSTRACT: Biological processes are being applied to nitrogen removal from wastewater. The conventional process is based on nitrification followed by denitrification. In nitrification process the ammoniacal nitrogen is oxidized to nitrate and it is strongly influenced by availability of dissolved oxygen. In this context, kinetics studies are an alternative used to evaluate the microorganisms activity by defining substrate (NH3-N) consumption and the influence of others parameters, like oxygen and substrate. The present study aims to evaluate the ammonium consumption rate by nitrification process at three different ammonia concentrations (100, 200 and 300 mg NH3-N L -1 ) at air flow rates of 20, 30, 50, 100, 200 and 500 mLair min−1 L −1 reactor. The kinetics were made by batch tests in an EGSB reactor at temperature of 25ºC for 2h30min. It was visualized that with 100 and 200 mg N-NH3 L - ¹ the substrate concentration was fully consumed. However, at the substrate concentration of 300 mg NH3-N L - ¹ an increase of substrate consumption was observed but ammonia was not entirely consumed. Furthermore, for the three initial ammonia concentrations, the behavior of substrate consumption was similar in function of air flow rate. Additionally, it was possible to conclude that as the supply of oxygen increased, the nitrogen ammoniacal consumption rate also increased

Professional Decision-Making in Research (PDR): The validity of a new measure

In this paper, we report on the development and validity of the Professional Decision-Making in Research (PDR) measure, a vignette-based test that examines decision-making strategies used by investigators when confronted with challenging situations in the context of empirical research. The PDR was administered online with a battery of validity measures to a group of NIH-funded researchers and research trainees who were diverse in terms of age, years of experience, types of research, and race. The PDR demonstrated adequate reliability (alpha = .84) and parallel form correlation (r = .70). As hypothesized, the PDR was significantly negatively correlated with narcissism, cynicism, moral disengagement, and compliance disengagement; it was not correlated with socially desirable responding. In regression analysis, the strongest predictors of higher PDR scores were low compliance disengagement, speaking English as a native language, conducting clinical research with human subjects, and low levels of narcissism. Given that the PDR was written at an eighth grade reading level to be suitable for use with English as a second language participants and that only one-fourth of items focused on clinical research, further research into the possible roles of culture and research ethics training across specialties is warranted. This initial validity study demonstrates the potential usefulness of the PDR as an educational outcome assessment measure and a research instrument for studies on professionalism and integrity in research

Key Features Relevant to Select Antigens and TCR From the MHC-Mismatched Repertoire to Treat Cancer

Adoptive transfer of T cells transgenic for tumor-reactive T-cell receptors (TCR) is an attractive immunotherapeutic approach. However, clinical translation is so far limited due to challenges in the identification of suitable target antigens as well as TCRs that are concurrent safe and efficient. Definition of key characteristics relevant for effective and specific tumor rejection is essential to improve current TCR-based adoptive T-cell immunotherapies. We here characterized in-depth two TCRs derived from the human leukocyte antigen (HLA)-mismatched allogeneic repertoire targeting two different myeloperoxidase (MPO)-derived peptides presented by the same HLA-restriction element side by side comprising state of the art biochemical and cellular in vitro, in vivo, and in silico experiments. In vitro experiments reveal comparable functional avidities, off-rates, and cytotoxic activities for both TCRs. However, we observed differences especially with respect to cytokine secretion and cross-reactivity as well as in vivo activity. Biochemical and in silico analyses demonstrate different binding qualities of MPO-peptides to the HLA-complex determining TCR qualities. We conclude from our biochemical and in silico analyses of peptide-HLA-binding that rigid and high-affinity binding of peptides is one of the most important factors for isolation of TCRs with high specificity and tumor rejection capacity from the MHC-mismatched repertoire. Based on our results, we developed a workflow for selection of such TCRs with high potency and safety profile suitable for clinical translation

The demise of the randomised controlled trial: bibliometric study of the German-language health care literature, 1948 to 2004

BACKGROUND: In order to reduce systematic errors (such as language bias) and increase the precision of the summary treatment effect estimate, a comprehensive identification of randomised controlled trials (RCT), irrespective of publication language, is crucial in systematic reviews and meta-analyses. We identified trials in the German general health care literature. METHODS: Eight German language general health care journals were searched for randomised controlled trials and analysed with respect to the number of published RCTs each year and the size of trials. RESULTS: A total of 1618 trials were identified with a median total number of 43 patients per trial. Between 1970 and 2004 a small but constant rise in sample size from a median number of 30 to 60 patients per trial can be observed. The number of published trials was very low between 1948 and 1970, but increased between 1970 and 1986 to a maximum of 11.2 RCTs per journal and year. In the following time period a striking decline of the number of RCTs was observed. Between 1999 and 2001 only 0.8 RCTs per journal and year were published, in the next three years, the number of published trials increased to 1.7 RCTs per journal and year. CONCLUSION: German language general health care journals no longer have a role in the dissemination of trial results. The slight rise in the number of published RCTs in the last three years can be explained by a change of publication language from German to English of three of the analysed journals

Molecular basis of telaprevir resistance due to V36 and T54 mutations in the NS3-4A protease of the hepatitis C virus

Structural analysis of the inhibitor Telaprevir (VX-950) of the hepatitis C virus (HCV) protease NS3-4A shows that mutations at V36 and/or T54 result in impaired interaction with VX-950, explaining the development of viral breakthrough variants

Ketoamide Resistance and Hepatitis C Virus Fitness in Val55 Variants of the NS3 Serine Protease

ABSTRACT Drug-resistant viral variants are a major issue in the use of direct-acting antiviral agents in chronic hepatitis C. Ketoamides are potent inhibitors of the NS3 protease, with V55A identified as mutation associated with resistance to boceprevir. Underlying molecular mechanisms are only partially understood. We applied a comprehensive sequence analysis to characterize the natural variability at Val55 within dominant worldwide patient strains. A residue-interaction network and molecular dynamics simulation were applied to identify mechanisms for ketoamide resistance and viral fitness in Val55 variants. An infectious H77S.3 cell culture system was used for variant phenotype characterization. We measured antiviral 50% effective concentration (EC 50 ) and fold changes, as well as RNA replication and infectious virus yields from viral RNAs containing variants. Val55 was found highly conserved throughout all hepatitis C virus (HCV) genotypes. The conservative V55A and V55I variants were identified from HCV genotype 1a strains with no variants in genotype 1b. Topology measures from a residue-interaction network of the protease structure suggest a potential Val55 key role for modulation of molecular changes in the protease ligand-binding site. Molecular dynamics showed variants with constricted binding pockets and a loss of H-bonded interactions upon boceprevir binding to the variant proteases. These effects might explain low-level boceprevir resistance in the V55A variant, as well as the Val55 variant, reduced RNA replication capacity. Higher structural flexibility was found in the wild-type protease, whereas variants showed lower flexibility. Reduced structural flexibility could impact the Val55 variant's ability to adapt for NS3 domain-domain interaction and might explain the virus yield drop observed in variant strains

Social presence and dishonesty in retail

Self-service checkouts (SCOs) in retail can benefit consumers and retailers, providing control and autonomy to shoppers independent from staff, together with reduced queuing times. Recent research indicates that the absence of staff may provide the opportunity for consumers to behave dishonestly, consistent with a perceived lack of social presence. This study examined whether a social presence in the form of various instantiations of embodied, visual, humanlike SCO interface agents had an effect on opportunistic behaviour. Using a simulated SCO scenario, participants experienced various dilemmas in which they could financially benefit themselves undeservedly. We hypothesised that a humanlike social presence integrated within the checkout screen would receive more attention and result in fewer instances of dishonesty compared to a less humanlike agent. This was partially supported by the results. The findings contribute to the theoretical framework in social presence research. We concluded that companies adopting self-service technology may consider the implementation of social presence in technology applications to support ethical consumer behaviour, but that more research is required to explore the mixed findings in the current study.<br/