Behaviour of doxycycline, oxytetracycline, tetracycline and flumequine during manure up-cycling for fertilizer production.

The fate of four widely used veterinary antibiotics (doxycycline, flumequine, oxytetracycline and tetracycline) during manure upcycling was investigated at laboratory and pilot scale. The pilot was operated continuously, while the laboratory scale in batch mode. Both set-ups consisted of anaerobic digestion, ammonia stripping and a solid liquid separation step. A partial nitritation anammox process was used to treat the laboratory scale effluent. In the pilot installation, pig manure as feed, natural occurring antibiotics levels were reduced by 92% for doxycycline, 88% for flumequine, 95% for oxytetracycline and 100% for tetracycline. In the laboratory scale set-up, antibiotic free sludge was used and the four substances were spiked. The input antibiotics concentration was reduced by 85% for doxycycline, 46% for flumequine, 97% for oxytetracycline and 100% for tetracycline. In both set-ups the centrifuge cake was identified as the major emission pathway for residual antibiotics. Manure upcycling, while producing fertilizers, can be considered effective in reducing the residual antibiotic load.

Nitrous oxide emissions of a mesh separated single stage deammonification reactor.

It is widely accepted that partial nitrification by ANAMMOX has the potential to become one of the key processes in wastewater treatment. However, large greenhouse gas emissions have been panobserved in many cases. A novel mesh separated reactor, developed to allow continuous operation of deammonification at smaller scale without external biomass selection, was compared to a conventional single-chamber deammonification sequencing batch reactor (SBR), where both were equally-sized pilot-scale reactors. The mesh reactor consisted of an aerated and an anoxic zone separated by a mesh. The resulting differences in the structure of the microbial community were detected by next-generation sequencing. When both systems were operated in a sequencing batch mode, both systems had comparable nitrous oxide emission factors in the range of 4% to 5% of the influent nitrogen load. A significant decrease was observed after switching from sequencing batch mode to continuous operation.

Validation of a KHV antibody enzyme-linked immunosorbent assay (ELISA).

Koi herpesvirus (KHV) causes KHV disease (KHVD). The virus is highly contagious in carp or koi and can induce a high mortality. Latency and, in some cases, a lack of signs presents a challenge for virus detection. Appropriate immunological detection methods for anti-KHV antibodies have not yet been fully validated for KHV. Therefore, it was developed and validated an enzyme-linked immunosorbent assay (ELISA) to detect KHV antibodies. The assay was optimized with respect to plates, buffers, antigens and assay conditions. It demonstrated high diagnostic and analytical sensitivity and specificity and was particularly useful at the pond or farm levels. Considering the scale of the carp and koi industry worldwide, this assay represents an important practical tool for the indirect detection of KHV, also in the absence of clinical signs.

New hybrid reactor concept incorporating a filter mesh for nitritation-anammox treatment of sludge return liquid.

A new approach to perform partial nitritation-anammox in a single tank was investigated. The tank incorporated a mesh (opening size 1.0 × 1.2 mm) as permeable barrier to create two distinct reaction zones (aerated and anoxic). The study reports on the operation and optimization of a 13 L laboratory scale reactor to treat sludge reject water with an NH4-N concentration of ∼750 mg·L-1. Performance throughout 250 days at increasing nitrogen loading rates is presented. The maximum loading rate applied was 1.5 kg NH4-N·m-3·d-1 at a hydraulic retention time of 12 h. Typical composition of the effluent was ∼50 mg·L-1 NH4-N; <5-10 mg·L-1 NO2-N and ∼60 mg·L-1 NO3-N. The corresponding average N removal rates were 85% for total nitrogen and 90% for NH4-N, respectively. Process control was very simple. It comprised only regulation of the aeration rate to maintain a pre-set pH (7.1) in the nitritation zone. Performance data clearly indicate that the investigated reactor configuration offers distinct advantages over currently installed processes. It demonstrated high robustness without the need for sophisticated process control. Apparently, the use of a permeable mesh to establish different reaction conditions in a single reactor provides new features of high potential.

Asymptomatic anal sexually transmitted infections in HIV-positive men attending anal cancer screening.

BACKGROUND: HIV-positive men who have sex with men (HIV+MSM) have an increased risk for anal dysplasia and for sexually transmitted infections (STIs). OBJECTIVES: We determined the positivity rates of Chlamydia trachomatis (CT), Neisseria gonorrhoea (NG), Mycoplasma genitalium (MG) and syphilis in HIV+MSM participating in an anal cancer screening programme. METHODS: In total, 852 intra-anal swabs were collected from 503 HIV+MSM between 2012 and 2014. Anal cytology and polymerase chain reaction assays for human papillomavirus (HPV), CT, NG and MG detection were performed. The syphilis status was determined serologically. Risk factors for STIs were explored by multiple logistic regression analysis. RESULTS: In total 20·7% (104 of 503) of the patients had an STI other than HPV within the study period. The most common was CT, found in 10·9%, followed by NG (8·9%) and MG (4·2%). Early syphilis was detected in 4·6% and past syphilis in 44·5% of the HIV+MSM. Eighteen patients (3·6%) had more than one STI episode, and 90·6% of the 127 cases of STIs were asymptomatic. Age, anal HPV infection, abnormal anal cytology and previous syphilis were risk factors for STI. CONCLUSIONS: Anal STIs are frequent and mostly asymptomatic in HIV+MSM participating in anal cancer screening. STI screening should be incorporated into anal cancer screening programmes for HIV+MSM.

The amino-terminal domain of ORF149 of koi herpesvirus is preferentially targeted by IgM from carp populations surviving infection.

Recombinantly expressed fragments of the protein encoded by ORF149 (pORF149), a structural protein from the common- and koi-carp-infecting cyprinid herpesvirus-3 (CyHV-3) that was previously shown to be antigenic, were used to obtain evidence that its amino-terminal part contains immunodominant epitopes in fish populations that survived the infection. To obtain such evidence, nonspecific binding of carp serum tetrameric IgM had to be overcome by a novel ELISA protocol (rec2-ELISA). Rec2-ELISA involved pre-adsorption of carp sera with a heterologous recombinant fragment before incubation with pORF149 fragments and detection with anti-carp IgM monoclonal antibodies. Only in this way was it possible to distinguish between sera from uninfected and survivor carp populations. Although IgM from survivors recognised pORF149 fragments to a lesser degree than whole virus, specificity was confirmed by correlation of rec2- and CyHV-3-ELISAs, inhibition of rec2-ELISA by an excess of frgIIORF149, ELISA using IgM-capture, Western blotting, and reduction of reactivity in CyHV-3-ELISA by pre-adsorption of sera with frgIIORF149. The similarity of IgM-binding profiles between frgIORF149 (amino acid residues 42-629) and frgIIORF149 (42-159) and their reactivities with previously described anti-CyHV-3 monoclonal antibodies confirmed that most pORF149 epitopes were localised in its amino-terminal part.

The male ScreenING Study: prevalence of HPV-related genital and anal lesions in an urban cohort of HIV-positive men in Germany.

BACKGROUND: Human papillomaviruses (HPV) induce condylomata, anogenital cancers and their precursor lesions as anal or penile intraepithelial neoplasia (AIN/PIN). HIV-positive individuals have an increased risk for the development of anogenital HPV-induced lesions. OBJECTIVE: Estimation of the prevalence of HPV-related anogenital benign and malignant lesions in HIV-infected men attending a screening programme. METHODS: Four hundred HIV-positive men [98% men who have sex with men (MSM)] were enrolled in this prospective study from 2008 to 2011. All patients received an inspection of the anogenital region, digital rectal examination, high-resolution anoscopy (HRA), anal cytology, anal/penile histology if required, and HPV-typing of anal and penile swabs. RESULTS: At baseline, 75% (n = 302) of the men had abnormal anal cytological/histological results. 41% presented with low-grade (n = 164), 24% with high-grade anal dysplasia (n = 95) and two men with invasive anal cancer. 2.3% had PIN (n = 9) and one patient had penile cancer at baseline. Throughout the study period, 75% had anal dysplasia (low-grade n = 177, high-grade n = 125), 3.3% (n = 13) had PIN and two further patients developed anal cancer. Within the study period, 52.8% (n = 211) had condylomata (49% anal, 15% penile, 11% anal plus penile condylomata). At baseline, 88.5% of anal and 39.3% of penile swabs were HPV-DNA positive, and 77.8% of anal and 26.5% of penile swabs carried high-risk HPV-types. HPV16 was the most frequent HPV-type. CONCLUSION: HIV-positive MSM have a high risk for HPV-induced condylomata, (pre)malignant anogenital lesions and anogenital cancers. Screening for HPV-induced dysplasia is crucial to avoid progression to invasive carcinomas. Additionally, HPV-vaccination recommendations should be extended to high-risk populations.

Assessment of the state of the art of technologies for the processing of digestate residue from anaerobic digesters.

Anaerobic digestion is widely used as an important source of renewable energy. With the increasing number and capacity of biogas plants also, adequate treatment technologies for whole digestate - the residue from anaerobic digestion - are gaining attention. In this study the state of the art of digestate processing is analysed, and currently used treatment schemes and the various technological processes involved are evaluated. The study combines data and experiences from existing large-scale digestate processing facilities in Austria, Germany, Switzerland and Italy, as well as know-how from technology providers and relevant research projects. However, the field of digestate processing is still quite new and little detailed information about the performance of different technologies at industrial scale is available. Digestate processing is gaining importance since digestate utilisation can become an important bottleneck when increasing biogas production. In addition, the production of renewable fertiliser from digestate is increasingly of interest to replace fossil fertilisers. This study is the first profound attempt to establish an assessment of the state-of-the-art technologies in use.

Anaerobic digestion of stillage fractions - estimation of the potential for energy recovery in bioethanol plants.

Stillage processing can require more than one third of the thermal energy demand of a dry-grind bioethanol production plant. Therefore, for every stillage fraction occurring in stillage processing the potential of energy recovery by anaerobic digestion (AD) was estimated. In the case of whole stillage up to 128% of the thermal energy demand in the process can be provided, so even an energetically self-sufficient bioethanol production process is possible. For wet cake the recovery potential of thermal energy is 57%, for thin stillage 41%, for syrup 40% and for the evaporation condensate 2.5%. Specific issues for establishing AD of stillage fractions are evaluated in detail; these are high nitrogen concentrations, digestate treatment and trace element supply. If animal feed is co-produced at the bioethanol plant and digestate fractions are to be reused as process water, a sufficient quality is necessary. Most interesting stillage fractions as substrates for AD are whole stillage, thin stillage and the evaporation condensate. For these fractions process details are presented.

Effects of pioglitazone versus simvastatin on biomarkers of inflammation in patients on high cardiovascular risk.

High levels of fetuin-A has been linked to cardiovascular disease, possibly via modulating low-grade systemic inflammation. We performed a subanalysis from the PIOSTAT study to investigate a possible link between fetuin-A and the inflammatory biomarker hs-CRP. 66 nondiabetic individuals at cardiovascular risk were randomized to either pioglitazone, simvastatin, or the combination of both, and followed for 12 weeks. At study endpoint, correlations between serum fetuin-A, hs-CRP, blood lipids, PAI-1, MMP-9, HOMA-IR, and liver transaminases were investigated by Spearman rank correlation. Changes in fetuin-A concentration did not correlate to changes in hs-CRP (r=0.19, p=0.16). A positive correlation was found for change of HOMA-IR value (r=0.33, p=0.01) and for the AST/ALT ratio (p<0.05). Our data suggest that the previously observed correlation between elevated circulating fetuin-A and hs-CRP in epidemiological studies may not reflect a causal relationship in nondiabetic patients on high cardiovascular risk.

Novel avian influenza virus vaccines.

Current vaccines against avian influenza (AI) virus infections are primarily based on classical inactivated whole-virus preparations. Although administration of these vaccines can protect poultry from clinical disease, sterile immunity is not achieved under field conditions, allowing for undetected virus spread and evolution under immune cover. Therefore, there is an urgent need for a robust and reliable system of differentiation between infected and vaccinated animals. Moreover, current AI vaccines must be administered individually, requiring the handling of excessively large numbers of animals, which makes it difficult to obtain high vaccine coverage. Consequently, AI vaccines conferring solid immunity that could be used for mass application would be advantageous. Several approaches are being pursued to improve existing vaccines and develop novel vaccines, all of which will be covered in this overview.

Pilot plant experiences using physical and biological treatment steps for the remediation of groundwater from a former MGP site.

The production of manufactured gas at a site in Vienna, Austria led to the contamination of soil and groundwater with various pollutants including PAHs, hydrocarbons, phenols, BTEX, and cyanide. The site needs to be remediated to alleviate potential impacts to the environment. The chosen remediation concept includes the excavation of the core contaminated site and the setup of a hydraulic barrier to protect the surrounding aquifer. The extracted groundwater will be treated on-site. To design the foreseen pump-and-treat system, a pilot-scale plant was built and operated for 6 months. The scope of the present study was to test the effectiveness of different process steps, which included an aerated sedimentation basin, a submerged fixed film reactor (SFFR), a multi-media filter, and an activated carbon filter. The hydraulic retention time (HRT) was 7.0 h during normal flow conditions and 3.5h during high flow conditions. The treatment system was effective in reducing the various organic and inorganic pollutants in the pumped groundwater. However, it was also demonstrated that appropriate pre-treatment was essential to overcome problems with clogging due to precipitation of tar and sulfur compounds. The reduction of the typical contaminants, PAHs and BTEX, was more than 99.8%. All water quality parameters after treatment were below the Austrian legal requirements for discharge into public water bodies.

Enhanced ammonium removal from liquid anaerobic digestion residuals in an advanced sequencing batch reactor system.

When treating effluents from anaerobic processing of organic wastes, the challenge lies in the large quantity of recalcitrant COD and in the high nitrogen content. The data presented in this study illustrate an advanced SBR concept that is able to significantly reduce the organic load. It was found that undigested mashed bio-waste bypassing the anaerobic digestion is highly suitable as an external carbon source to compensate deficiencies of readily biodegradable BOD required for denitrification. In order to utilize the carbon source as efficiently as possible, the SBR was operated in a mode by which nitrification/denitrification is achieved by a shortcut process using nitrite. This procedure reduced the requirement of an external carbon source to only 5% (v/v). Moreover, through an optimized SBR sequence for an influent concentration of 14,000 mg COD/l and 3,800 mg TN/l, nearly complete removal of nitrogen (>95%) was achieved. The average removal rates for COD and BOD were 83% and 86%, respectively. The applied hydraulic retention time (HRT) of the SBR was 6.8 days. The elevated temperature of 30-41 degrees C in the reactor as a result of the high biological activity was advantageous in terms of enhanced reaction kinetics and also provided better process stability.

Ammonium removal from anaerobic digester effluent by ion exchange.

The effluent of a 500 kW biogas plant is treated with a solid separation, a micro filtration and a reverse osmosis to achieve nutrient recovery and an effluent quality which should meet disposal quality into public water bodies. After the reverse osmosis, the ammonium concentration is still high (NH(4)-N = 467 mg/l), amongst other cations (K+ = 85 mg/l; Na+ = 67 mg/l; Mg2+ = 0.74 mg/l; Ca2+= 1.79 mg/l). The aim of this study was to remove this ammonium by ion exchange. Acidic gel cation exchange resins and clinoptilolite were tested in column experiments to evaluate their capacity, flow rates and pH. Amberjet 1,500 H was the most efficient resin, 57 BV of the substrate could be treated, 1.97 mol NH4-N/l resin were removed. The ammonium removal was more than 99% and the quality of the effluent was very satisfactory (NH4-N < 2 mg/l). The breakthrough of the observed parameters happened suddenly, the order was sodium-pH-ammonium-potassium. The sharp increase of the pH facilitates the online control, while the change in conductivity is less significant. A regeneration with 3 bed volumes of 2 M HCl recovered 91.7% of the original cation exchange capacity.

Effects of partial maize silage substitution with microalgae on viscosity and biogas yields in continuous AD trials.

The microalga Acutodesmus obliquus was investigated as a feedstock in semi-continuously fed anaerobic digestion trials, where A. obliquus was co-digested with pig slurry and maize silage. Maize silage was substituted by both 10% and 20% untreated, and 20% ultrasonicated microalgae biomass on a VS (volatile solids) basis. The substitution of maize silage with 20% of either ultrasonicated and untreated microalgae led to significantly lower biogas yields, i.e., 560 dm³ kg-1 VScorr in the reference compared to 516 and 509 dm³ kg-1VScorr for untreated and ultrasonicated microalgae substitution. Further, the viscosities in the different reactors were measured at an OLR of 3.5 g VS dm-3 d-1. However, all treatments with microalgae resulted in significantly lower viscosities. While the mean viscosity reached 0.503 Pa s in the reference reactor, mean viscosities were 53% lower in reactors where maize was substituted by 20% microalgae, i.e. 0.239 Pa s, at a constant rotation speed of 30 rpm. Reactors where maize was substituted by 20% ultrasonicated microalgae had a 32% lower viscosity, for 10% microalgae substitution a decrease of 8% was measured. Decreased viscosities have beneficial effect on the bioprocess and the economy in biogas plants. Nonetheless, with regard to other parameters, no positive effect on biogas yields by partial substitution with microalgae biomass was found. The application of microalgae may be an interesting option in anaerobic digestion when fibrous or lignocellulosic substances lead to high viscosities of the digested slurries. High production costs remain the bottleneck for making microalgae an interesting feedstock.

Cyanobacteria Biorefinery - Production of poly(3-hydroxybutyrate) with Synechocystis salina and utilisation of residual biomass.

This study evaluates a biorefinery concept for producing poly(3-hydroxybutyrate) (PHB) with the cyanobacterial strain Synechocystis salina. Due to this reason, pigment extraction and cell disruption were investigated as pre-treatment steps for the harvested cyanobacterial biomass. The results demonstrated that at least pigment removal was necessary to obtain PHB with processable quality (weight average molecular weight: 569-988kgmol-1, melting temperature: 177-182°C), which was comparable to heterotrophically produced PHB. The removed pigments could be utilised as additional by-products (chlorophylls 0.27-1.98mgg-1 TS, carotenoids 0.21-1.51mgg-1 TS, phycocyanin 0-127mgg-1 TS), whose concentration depended on the used nutrient source. Since the residual biomass still contained proteins (242mgg-1 TS), carbohydrates (6.1mgg-1 TS) and lipids (14mgg-1 TS), it could be used as animal feed or converted to biomethane (348 mn3 t-1VS) and fertiliser. The obtained results indicate that the combination of photoautotrophic PHB production with pigment extraction and utilisation of residual biomass offer the highest potential, since it contributes to decrease the environmental footprint of the process and because biomass could be used in a cascading way and the nutrient cycle could be closed.

Maximizing the production of butyric acid from food waste as a precursor for ABE-fermentation.

The current study reports on the maximization of butyric acid production from food waste using a mixed microbial fermentation. In semi-continuous fermentations the effect of three different pH values (5.5, 7.0 and 9.0), three different temperatures (37°C, 55°C and 70°C) and two levels of hydraulic retention time (HRT, 2days and 6days) on the formation of butyric acid as well as total volatile fatty acid production (tVFA) were investigated. Overall, pH5.5 provided the lowest butyric acid concentrations regardless of the temperature and the HRT. At mesophilic temperature (37°C) alkaline conditions (pH9.0) lead to a strong incline of tVFA as well as butyric acid concentration probably due to a decreased solubilization of the substrate. However, most efficient in terms of butyric acid production was the fermentation conducted at 55°C and pH7 where a butyric acid concentrations of 10.55g/L (HRT 2days) and 13.00g/L (HRT 6days) were achieved. Additional experiments at 70°C showed declining butyric acid production. Increase of the HRT from 2days to 6days provided an increment of butyric acid concentration throughout almost all experimental settings. However, regarding volumetric productivity the increase in concentration does not compensate for the bigger reactor volume required to establish a higher HRT. At pH7 and 55°C the resulting volumetric production rates were 5.27g/L∗d at a HRT 2days and only 2.17g/L∗d at a HRT of 6days.

A novel processing method for injection-molded polyether-urethane scaffolds. Part 1: processing.

A large-scale scaffold processing method with injection molding has been successfully developed. Water was used as afoaming agent for the new technique. NaCl was used as a porogen to achieve an open-cell structure. Organic solvents, which are common foaming agents for polyurethane, where not used. Toxic remains in the polymer were therefore prevented. Pore size and porosity was adjustable through process parameters. A parameter study showed that an increase in injection pressure, plasticize speed, cylinder, and mold temperature raised the mean pore diameter. The porosity also could be mended by the cylinder and mold temperature, in addition to NaCl concentration. It was possible to produce scaffolds with a porosity of 64 +/- 3%, a pore size distribution from 30-450 microm, and a mean pore diameter of 270 +/- 90 microm. The interconnective pores were found to lie between 5 and 58 microm.

Processing recommendations for using low-solids digestate as nutrient solution for poly-ß-hydroxybutyrate production with Synechocystis salina.

Within the last decades, environmental pollution with persistent plastics steadily increased; therefore the production of biodegradable materials like poly-ß-hydroxybutyrate (PHB) is essential. Currently, PHB is produced with heterotrophic bacteria from crops. This leads to competition with food and feed production, which can be avoided by using photoautotrophic cyanobacteria, as Synechocystis salina, synthesizing PHB from CO2 at nutrient limitation. This study aims to increase the economic efficiency of PHB production with cyanobacteria by using nutrients from anaerobic digestate. First, growth and PHB production of S. salina in digestate fractions (supernatant and permeate, with/without precipitating agents) and dilutions thereof and then the scale-up (photobioreactor, 200 L working volume) were evaluated. With precipitated and centrifuged digestate diluted 1/3 the highest biomass (1.55gL-1) and PHB concentrations (95.4mgL-1), being 78% of those in mineral media, were achieved. In the photobioreactor-experiments biomass (1.63gL-1) and PHB concentrations (88.7mgL-1), being 79% and 72% of those in mineral medium, were reached, but in a cultivation time 10days longer than in mineral medium. The possibility to use digestate as sustainable and low cost nutrient solution for microalgae cultivation and photoautotrophic PHB production, instead of applying it on fields or processing it to achieve discharge limits, makes this application a highly valid option.

Influence of the gas composition on the efficiency of ammonia stripping of biogas digestate.

Impact of strip gas composition on side stream ammonia stripping, a technology aiming at the reduction of high ammonia levels in anaerobic reactors, was investigated. Evaluation of the effect of oxygen contact during air stripping showed a distinct, though lower than perceived, inhibition of anaerobic microflora. To circumvent, the feasibility and possible constraints of biogas and flue gas as alternatives in side stream stripping were studied. Experiments, with ammonia bicarbonate model solution and digestate, were conducted. It was demonstrated that the stripping performance is negatively correlated to the CO2 level in the strip gas with a progressive performance loss towards higher concentrations. In contrast to biogas with its high CO2 content, the efficiency reduction observed for flue gas was significantly less pronounced. The later provides the additional benefit that its high thermal energy can be re-utilized in the stripping unit and it is therefore considered a viable alternative for air.