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1.
Water Res ; 230: 119543, 2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36628868

ABSTRACT

The applicability of chemical actinometry to characterize the fluence in UV reactors with reflections, non-parallel light, and variable water transmittance is limited due to the unknown effective path length or hydraulic shortcuts within the reactor. In this study, the effects of reflection and transmittance on actinometry were examined and a new, optimized and easy method for determining fluence was developed. KI/KIO3 and uridine actinometry experiments were carried out under controlled conditions using a collimated beam apparatus and a completely mixed batch reactor with or without diffuse reflection and compared to biodosimetry results. Whereas optically opaque actinometers such as KI/KIO3 are not directly capable of predicting the fluence of reflecting reactors, the results of uridine actinometry are influenced by reflection and transmission. To precisely predict the fluence rate in UV reactors with uridine, knowledge about the effective optical path length of the light is needed. Here, an existing method to mathematically calculate the optical path length was adopted and optimized for uridine actinometry. Results for average fluence were validated by biodosimetry using MS2 phages under different degrees of reflection and transmission. It could be shown that by modifying the bottom of the reactor with diffusely reflecting polytetrafluoroethylene foil, the fluence rate was increased by a factor of approximately 2.6 and the path length by factor of 2.4. When only half of the bottom was covered with reflective foil, fluence rate increased by a factor of 1.8 and path length by 1.8. Although this new approach cannot replace biodosimetry, to predict the fluence distribution received by microorganisms, it can provide means to characterize more complex reactor designs, validate results of advanced reactor modeling, and quantify fluence for non-parallel irradiation and reflective light, especially for the application of high fluence (e.g., advanced oxidation processes), where biodosimetry may be too sensitive. Further, comparing the fluence obtained with actinometry to the results of biodosimetry might qualitatively indicate hydraulic short cuts or unideal fluence distributions for flow-through reactors.


Subject(s)
Ultraviolet Rays , Water Purification , Disinfection/methods , Water Purification/methods , Levivirus
2.
Sci Rep ; 9(1): 16110, 2019 11 06.
Article in English | MEDLINE | ID: mdl-31695073

ABSTRACT

We present an approach for fabrication of reproducible, chemically and mechanically robust functionalized layers based on MgF2 thin films on thin glass substrates. These show great advantages for use in super-resolution microscopy as well as for multi-electrode-array fabrication and are especially suited for combination of these techniques. The transparency of the coated substrates with the low refractive index material is adjustable by the layer thickness and can be increased above 92%. Due to the hydrophobic and lipophilic properties of the thin crystalline MgF2 layers, the temporal stable adhesion needed for fixation of thin tissue, e.g. cryogenic brain slices is given. This has been tested using localization-based super-resolution microscopy with currently highest spatial resolution in light microscopy. We demonstrated that direct stochastic optical reconstruction microscopy revealed in reliable imaging of structures of central synapses by use of double immunostaining of post- (homer1 and GluA2) and presynaptic (bassoon) marker structure in a 10 µm brain slice without additional fixing of the slices. Due to the proven additional electrical insulating effect of MgF2 layers, surfaces of multi-electrode-arrays were coated with this material and tested by voltage-current-measurements. MgF2 coated multi-electrode-arrays can be used as a functionalized microscope cover slip for combination with live-cell super-resolution microscopy.

3.
Water Res ; 163: 114857, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31336207

ABSTRACT

Many chemicals with different physico-chemical properties are present in municipal wastewater. In this study, the removal of a broad range of trace organic chemicals (TOrCs) was determined in two biological treatment processes differing in hydraulic retention time: sequential biofiltration (SBF) and soil-aquifer treatment (SAT), operated in Germany and Spain. Occurrence and the degree of removal of more than 150 TOrCs with different physico-chemical properties were analysed, including precursors as well as human metabolites and environmental transformation products (TPs). Ninety TOrCs were detected in the feed water of the SBF system, 40% of these showed removal efficiencies of higher than 30% during biological treatment. In SAT, 70 TOrCs were detected in the feed water, 60% of these could be reduced by more than 30% after approximately 3 days of subsurface treatment. For uncharged and negatively charged TOrCs biological degradation was mainly responsible for the removal, while positively charged TOrCs were most likely also removed by ionic interactions. The detections of TPs confirmed that biodegradation was a major removal process in both systems. The analysis of positively and negatively charged, neutral and zwitterionic TOrCs and the simultaneous analysis of precursors and their biologically formed TPs enabled a detailed understanding of underlying mechanisms of their removal in the two systems. On this basis, criteria for site-specific indicator selection were proposed.


Subject(s)
Groundwater , Water Pollutants, Chemical , Water Purification , Germany , Organic Chemicals , Soil , Spain
4.
Sci Total Environ ; 685: 596-608, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31195321

ABSTRACT

The World Health Organization (WHO) has identified the spread of antibiotic resistance as one of the major risks to global public health. An important transfer route into the aquatic environment is the urban water cycle. In this paper the occurrence and transport of antibiotic microbial resistance in the urban water cycle are critically reviewed. The presence of antibiotic resistance in low impacted surface water is being discussed to determine background antibiotic resistance levels, which might serve as a reference for treatment targets in the absence of health-based threshold levels. Different biological, physical and disinfection/oxidation processes employed in wastewater treatment and their efficacy regarding their removal of antibiotic resistant bacteria and antibiotic resistance geness (ARGs) were evaluated. A more efficient removal of antibiotic microbial resistance abundances from wastewater effluents can be achieved by advanced treatment processes, including membrane filtration, ozonation, UV-irradiation or chlorination, to levels typically observed in urban surface water or low impacted surface water.


Subject(s)
Drug Resistance, Microbial , Waste Disposal, Fluid/methods , Disinfection/methods , Wastewater
5.
Nutr Metab Cardiovasc Dis ; 28(4): 411-417, 2018 04.
Article in English | MEDLINE | ID: mdl-29395637

ABSTRACT

BACKGROUND AND AIM: B-vitamins may influence DNA methylation. We studied the effects of vitamin D + Ca + B versus D + Ca on epigenetic age markers and biological age. METHODS AND RESULTS: Participants (mean ± SD of age = 68.4 ± 10.1 years) were randomized to receive 1200 IE vitamin D3 plus 800 mg Ca-carbonate alone (n = 31) or with 0.5 mg B9, 50 mg B6, and 0.5 mg B12 (n = 32). The CpG methylation of 3 genes (ASPA, ITGA2B, and PDE4C) and the changes in methylation were compared between the groups after 1 year. The changes of ASPA methylation from baseline were higher in the D + Ca + B than in the D + Ca group (1.40 ± 4.02 vs. -0.96 ± 5.12, respectively; p = 0.046, adjusted for age, sex, and baseline methylation). The changes in PDE4C from baseline were slightly higher in the D + Ca + B group (1.95 ± 3.57 vs. 0.22 ± 3.57; adjusted p = 0.062). Methylation of ITGA2B and its changes from baseline were not different between the intervention groups. Sex-adjusted odds ratio of accelerated aging (chronological age < biological age at 1 year) was 5.26 (95% confidence interval 1.51-18.28) in the D + Ca + B compared with the D + Ca group. Accelerated aging in both groups was associated with younger age. In the D + Ca + B group, it was additionally associated with lower baseline homocysteine. CONCLUSIONS: Vitamin D + Ca + B and D + Ca differentially affected epigenetic age markers, although the effect size appeared to be small after 1 year. B-vitamins effect in young subjects with low homocysteine requires further investigation. ClinicalTrials.gov ID: NCT02586181.


Subject(s)
Aging/genetics , Calcium Carbonate/administration & dosage , Cholecalciferol/administration & dosage , CpG Islands/drug effects , DNA Methylation/drug effects , Dietary Supplements , Epigenesis, Genetic/drug effects , Vitamin B Complex/administration & dosage , Age Factors , Aged , Aged, 80 and over , Aging/blood , Double-Blind Method , Female , Folic Acid/administration & dosage , Germany , Homocysteine/blood , Humans , Male , Middle Aged , Time Factors , Treatment Outcome , Vitamin B 12/administration & dosage , Vitamin B 6/administration & dosage
6.
Nat Commun ; 9(1): 150, 2018 01 11.
Article in English | MEDLINE | ID: mdl-29323136

ABSTRACT

Quantum theory is expected to govern the electromagnetic properties of a quantum metamaterial, an artificially fabricated medium composed of many quantum objects acting as artificial atoms. Propagation of electromagnetic waves through such a medium is accompanied by excitations of intrinsic quantum transitions within individual meta-atoms and modes corresponding to the interactions between them. Here we demonstrate an experiment in which an array of double-loop type superconducting flux qubits is embedded into a microwave transmission line. We observe that in a broad frequency range the transmission coefficient through the metamaterial periodically depends on externally applied magnetic field. Field-controlled switching of the ground state of the meta-atoms induces a large suppression of the transmission. Moreover, the excitation of meta-atoms in the array leads to a large resonant enhancement of the transmission. We anticipate possible applications of the observed frequency-tunable transparency in superconducting quantum networks.

7.
Allergy ; 71(12): 1794-1799, 2016 12.
Article in English | MEDLINE | ID: mdl-27588368

ABSTRACT

Human sera are the first choice as controls for diagnostic applications such as immunoassays, but are limited regarding availability, varying quality, and high costs. In this study, we aimed to circumvent these limitations by the use of a chimeric adaptor molecule comprising the extracellular domains of the human FcγRI (CD64) fused with human IgE Fc domains (CD64-IgE Fc). Allergen-specific antibodies were produced in rabbits using eight different allergens, extracts, and allergen mixtures including mites, pollen, drugs, and food. Preincubation of polyclonal IgG with CD64-IgE Fc established allergen-specific artificial sera that showed comparable results for more than 20 allergens and allergen extracts in three diagnostic systems for the determination of specific IgE. The agreement for these artificial sera is within ±1 radioallergosorbent test (RAST) class. Hence, rabbit IgG complexed with the IgG-specific CD64-IgE Fc adaptor molecule could provide a substitute for human reference sera with specificity for virtually any protein of interest.


Subject(s)
Allergens/immunology , Antibodies/immunology , Blood Substitutes/adverse effects , Immunoglobulin E/immunology , Receptors, IgG/immunology , Recombinant Fusion Proteins/immunology , Antibodies/genetics , Antibody Specificity/immunology , Cell Line , Enzyme-Linked Immunosorbent Assay , Gene Expression , Humans , Immunization , Immunoglobulin E/chemistry , Immunoglobulin E/genetics , Immunoglobulin G/genetics , Immunoglobulin G/immunology , Protein Binding/immunology , Protein Domains/genetics , Protein Domains/immunology , Receptors, IgG/chemistry , Receptors, IgG/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism
8.
BMC Med Inform Decis Mak ; 16: 10, 2016 Jan 27.
Article in English | MEDLINE | ID: mdl-26818464

ABSTRACT

BACKGROUND: The majority of health IT adoption research focuses on the later stages of the IT adoption process: namely on the implementation phase. The first stage, however, which is defined as the knowledge-stage, remains widely unobserved. Following Rogers' Diffusion of Innovation Theory (DOI) this paper presents a research framework to examine the possible lack of shared IT awareness-knowledge, i.e. an information gradient, of two crucial stakeholders, the Chief Information Officer (CIO) and the Director of Nursing (DoN). This study shall answer the following research questions: (1.) Does this gradient exist? (2.) Which direction does it have? (3.) Are certain health IT (HIT) attributes associated with a potential gradient? (4.) Which determinants of diffusion go along with this gradient? METHOD: Results of two surveys that focused on the topic "IT support of clinical workflows" from the viewpoint of CIOs and DoNs with corresponding datasets from 75 hospitals were used in a secondary data analysis. The gradient was operationalised by measuring the disagreement of CIOs and DoNs on the availability and implementation status of 29 IT functions. HIT attributes tested were relevance and market penetration of the IT functions, determinants of diffusion were inter-professional leadership and IT service density. RESULTS: The analysis revealed a significant disagreement on the availability of 9 out of 29 HIT functions. In 23 HIT functions, the CIOs reported a higher implementation status than the DoNs, which pointed to a trend for a unidirectional gradient. The disagreement was significantly lower when the relevance of the IT function was high. Both determinants of diffusion correlated significantly negative with the degree of disagreement. CONCLUSION: This is the first study to empirically examine shared awareness-knowledge of two IT-stakeholders that are crucial for triggering IT adoption on the frontline level in hospitals. It could be shown that a gradient and thus a lack of shared awareness-knowledge existed and was associated with certain factors. In conclusion, hospitals should implement improved cooperation between IT staff and clinicians and IT service density when establishing the prerequisites for successful IT adoption processes.


Subject(s)
Administrative Personnel/organization & administration , Diffusion of Innovation , Health Information Management/organization & administration , Medical Informatics/organization & administration , Humans , Nursing
9.
Methods Inf Med ; 54(5): 424-33, 2015.
Article in English | MEDLINE | ID: mdl-26419492

ABSTRACT

BACKGROUND: Availability and usage of individual IT applications have been studied intensively in the past years. Recently, IT support of clinical processes is attaining increasing attention. The underlying construct that describes the IT support of clinical workflows is clinical information logistics. This construct needs to be better understood, operationalised and measured. OBJECTIVES: It is therefore the aim of this study to propose and develop a workflow composite score (WCS) for measuring clinical information logistics and to examine its quality based on reliability and validity analyses. METHODS: We largely followed the procedural model of MacKenzie and colleagues (2011) for defining and conceptualising the construct domain, for developing the measurement instrument, assessing the content validity, pretesting the instrument, specifying the model, capturing the data and computing the WCS and testing the reliability and validity. RESULTS: Clinical information logistics was decomposed into the descriptors data and information, function, integration and distribution, which embraced the framework validated by an analysis of the international literature. This framework was refined selecting representative clinical processes. We chose ward rounds, pre- and post-surgery processes and discharge as sample processes that served as concrete instances for the measurements. They are sufficiently complex, represent core clinical processes and involve different professions, departments and settings. The score was computed on the basis of data from 183 hospitals of different size, ownership, location and teaching status. Testing the reliability and validity yielded encouraging results: the reliability was high with r(split-half) = 0.89, the WCS discriminated between groups; the WCS correlated significantly and moderately with two EHR models and the WCS received good evaluation results by a sample of chief information officers (n = 67). These findings suggest the further utilisation of the WCS. CONCLUSION: As the WCS does not assume ideal workflows as a gold standard but measures IT support of clinical workflows according to validated descriptors a high portability of the WCS to other hospitals in other countries is very likely. The WCS will contribute to a better understanding of the construct clinical information logistics.


Subject(s)
Benchmarking/methods , Health Information Systems/organization & administration , Medical Informatics/classification , Medical Informatics/standards , Program Evaluation/methods , Workflow , Algorithms , Germany , Health Information Systems/classification
10.
Methods Inf Med ; 54(5): 385-7, 2015.
Article in English | MEDLINE | ID: mdl-26395286

ABSTRACT

The demand for evidence-based health informatics and benchmarking of 'good' information systems in health care gives an opportunity to continue reporting on recent papers in the German journal GMS Medical Informatics, Biometry and Epidemiology (MIBE) here. The publications in focus deal with a comparison of benchmarking initiatives in German-speaking countries, use of communication standards in telemonitoring scenarios, the estimation of national cancer incidence rates and modifications of parametric tests. Furthermore papers in this issue of MIM are introduced which originally have been presented at the Annual Conference of the German Society of Medical Informatics, Biometry and Epidemiology. They deal as well with evidence and evaluation of 'good' information systems but also with data harmonization, surveillance in obstetrics, adaptive designs and parametrical testing in statistical analysis, patient registries and signal processing.


Subject(s)
Delivery of Health Care/standards , Delivery of Health Care/trends , Health Information Systems/standards , Health Information Systems/trends , Quality Assurance, Health Care/standards , Quality Assurance, Health Care/trends , Epidemiologic Methods , Germany
11.
Methods Inf Med ; 54(5): 412-23, 2015.
Article in English | MEDLINE | ID: mdl-26391999

ABSTRACT

BACKGROUND: Clinical handovers at changes of shifts are typical scenarios of time restricted and information intensive communication, which are highly cognitively demanding. The currently available applications supporting handovers typically present complex information in a textual checklist-like manner. This presentation style has been criticised for not meeting the specific user requirements. OBJECTIVES: We, therefore, aimed at developing a concept for visualising the overview of a clinical case that serves as an alternative way to checklist-like presentations in clinical handovers. We also aimed at implementing this concept in a handoverEHR in order to support the pre-handover phase, the actual handover, and the post-handover phase as well as at evaluating its usability and attractiveness. RESULTS: We developed and implemented a concept that draws on Tolman's pioneering work on cognitive maps that we designed in accordance with Gestalt principles. These maps provide a pictorial overview of a clinical case. The application to build, manipulate, and store the cognitive maps was integrated into an openEHR based handover record that extends conventional records with handover specific information. Usability (n = 28) and attractiveness (n = 26) testing with experienced clinicians resulted in good ratings for suitability for the task as well as for attractiveness and pragmatism. CONCLUSION: We propose cognitive maps to represent and visualise the clinical case in situations where there is limited time to present complex information.


Subject(s)
Checklist/methods , Electronic Health Records/organization & administration , Hospital Communication Systems/organization & administration , Information Dissemination/methods , Patient Handoff/organization & administration , User-Computer Interface , Meaningful Use , Medical Record Linkage/methods , Models, Theoretical , Software , Software Design , Utilization Review
12.
Water Res ; 84: 315-22, 2015 Nov 01.
Article in English | MEDLINE | ID: mdl-26255129

ABSTRACT

The Shafdan reclamation project facility (Tel Aviv, Israel) practices soil aquifer treatment (SAT) of secondary effluent with hydraulic retention times (HRTs) of a few months to a year for unrestricted agricultural irrigation. During the SAT, the high oxygen demand (>40 mg L(-1)) of the infiltrated effluent causes anoxic conditions and mobilization of dissolved manganese from the soil. An additional emerging problem is the occurrence of persistent trace organic compounds (TrOCs) in reclaimed water that should be removed prior to reuse. An innovative hybrid process based on biofiltration, ozonation and short SAT with ∼22 d HRT is proposed for treatment of the Shafdan secondary effluent to overcome limitations of the existing system and to reduce the SAT's physical footprint. Besides efficient removal of particulate matter to minimize clogging, coagulation/flocculation and filtration (5-6 m h(-1)) operated with the addition of hydrogen peroxide as an oxygen source efficiently removed dissolved organic carbon (DOC, to 17-22%), ammonium and nitrite. This resulted in reduced effluent oxygen demand during infiltration and oxidant (ozone) demand during ozonation by 23 mg L(-1) and 1.5 mg L(-1), respectively. Ozonation (1.0-1.2 mg O3 mg DOC(-1)) efficiently reduced concentrations of persistent TrOCs and supplied sufficient dissolved oxygen (>30 mg L(-1)) for fully oxic operation of the short SAT with negligible Mn(2+) mobilization (<50 µg L(-1)). Overall, the examined hybrid process provided DOC reduction of 88% to a value of 1.2 mg L(-1), similar to conventional SAT, while improving the removal of TrOCs and efficiently preventing manganese dissolution.


Subject(s)
Organic Chemicals/metabolism , Water Pollutants, Chemical/metabolism , Water Purification/methods , Filtration , Waste Disposal, Fluid
13.
Sci Rep ; 5: 8217, 2015 Feb 03.
Article in English | MEDLINE | ID: mdl-25645753

ABSTRACT

Vancomycin resistant enterococci (VRE) constitute a challenging problem in health care institutions worldwide. Novel methods to rapidly identify resistances are highly required to ensure an early start of tailored therapy and to prevent further spread of the bacteria. Here, a spectroscopy-based rapid test is presented that reveals resistances of enterococci towards vancomycin within 3.5 hours. Without any specific knowledge on the strain, VRE can be recognized with high accuracy in two different enterococci species. By means of dielectrophoresis, bacteria are directly captured from dilute suspensions, making sample preparation very easy. Raman spectroscopic analysis of the trapped bacteria over a time span of two hours in absence and presence of antibiotics reveals characteristic differences in the molecular response of sensitive as well as resistant Enterococcus faecalis and Enterococcus faecium. Furthermore, the spectroscopic fingerprints provide an indication on the mechanisms of induced resistance in VRE.


Subject(s)
Enterococcus faecalis/drug effects , Enterococcus faecium/drug effects , Vancomycin/pharmacology , Enterococcus faecalis/chemistry , Enterococcus faecium/chemistry , Spectrum Analysis, Raman , Time Factors , Vancomycin Resistance
14.
Methods Inf Med ; 54(4): 319-27, 2015.
Article in English | MEDLINE | ID: mdl-25510406

ABSTRACT

OBJECTIVES: eHealth and innovation are often regarded as synonyms - not least because eHealth technologies and applications are new to their users. This position paper challenges this view and aims at exploring the nature of eHealth innovation against the background of common definitions of innovation and facts from the biomedical and health informatics literature. A good understanding of what constitutes innovative eHealth developments allows the degree of innovation to be measured and interpreted. METHODS: To this end, relevant biomedical and health informatics literature was searched mainly in Medline and ACM digital library. This paper presents seven facts about implementing and applying new eHealth developments hereby drawing on the experience published in the literature. RESULTS: The facts are: 1. eHealth innovation is relative. 2. Advanced clinical practice is the yardstick. 3. Only used and usable eHealth technology can give birth to eHealth innovatio. 4. One new single eHealth function does not make a complex eHealth innovation. 5. eHealth innovation is more evolution than revolution. 6. eHealth innovation is often triggered behind the scenes; and 7. There is no eHealth innovation without sociocultural change. CONCLUSIONS: The main conclusion of the seven facts is that eHealth innovations have many ingredients: newness, availability, advanced clinical practice with proven outcomes, use and usability, the supporting environment, other context factors and the stakeholder perspectives. Measuring eHealth innovation is thus a complex matter. To this end we propose the development of a composite score that expresses comprehensively the nature of eHealth innovation and that breaks down its complexity into the three dimensions: i) eHealth adoption, ii) partnership with advanced clinical practice, and iii) use and usability of eHealth. In order to better understand the momentum and mechanisms behind eHealth innovation the fourth dimension, iv) eHealth supporting services and means, needs to be studied. Conceptualising appropriate measurement instruments also requires eHealth innovation to be distinguished from eHealth sophistication, performance and quality, although innovation is intertwined with these concepts. The demanding effort for defining eHealth innovation and measuring it properly seem worthwhile and promise advances in creating better systems. This paper thus intends to stimulate the necessary discussion.


Subject(s)
Diffusion of Innovation , Medical Informatics/trends , Electronic Health Records , Leadership , Patient-Centered Care
15.
Nanotechnology ; 25(44): 445203, 2014 Nov 07.
Article in English | MEDLINE | ID: mdl-25319270

ABSTRACT

We investigated silver-covered polymer based nanogratings as substrates for surface-enhanced Raman spectroscopy (SERS), in particular with respect to the thickness of the plasmonically active silver film. In order to obtain accurate geometrical input data for the simulation process, we inspected cross sections of the gratings prepared by breaking at cryogenic temperature. We noticed a strong dependence of the simulation results on geometrical variations of the structures. Measurements revealed that an increasing silver film thickness on top of the nanogratings leads to a blue shift of the plasmonic resonance, as predicted by numerical simulations, as well as to an increased field enhancement for an excitation at 488 nm. We found a clear deviation of the experimental data compared to the simulated results for very thin silver films due to an island-like growth at a silver thickness below 20 nm. In order to investigate the SERS activity. we carried out measurements with crystal violet as a model analyte at an excitation wavelength of 488 nm. The SERS enhancement increases up to a silver thickness of about 30 nm, whereas it remains nearly constant for thicker silver films.

16.
Water Res ; 49: 34-43, 2014 Feb 01.
Article in English | MEDLINE | ID: mdl-24316180

ABSTRACT

Ozonation is known as an efficient treatment to reduce the concentration of many trace organic compounds from WWTP effluents, but the formation of unknown and possibly persistent and toxic transformation products has to be considered. In this paper tertiary treatment of wastewater by the combination of ozone and soil aquifer treatment was investigated with respect to the removal of the antiepileptic drug carbamazepine (CBZ, 10 µg/L) and its transformation products. Batch tests and pilot experiments confirmed efficient removal of carbamazepine from secondary effluent by ozone. With typical ozone consumption of 0.7 mg O3/mg DOC0, approx. 50% of the transformed CBZ was detected as its primary product 1-(2-benzaldehyde)-4-hydro-(1H,3H)-quinazoline-2-one (BQM). Structure proposals and a formation pathway were elaborated for a total of 13 ozonation products of CBZ. In subsequent biological treatment BQM turned out to be more effectively biodegraded than CBZ. Its aldehyde group was quickly oxidized to a carboxylic acid (BaQM), which was removed in sand column experiments. Most of the minor ozonation products of CBZ persisted in sand column experiments with residence times of 5-6 days. Non-target screening of column effluent revealed no formation of persistent biotransformation products.


Subject(s)
Carbamazepine/isolation & purification , Groundwater/chemistry , Ozone/chemistry , Soil/chemistry , Waste Disposal, Fluid , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Biotransformation , Carbamazepine/chemistry , Chromatography, Liquid , Kinetics , Mass Spectrometry , Oxidation-Reduction , Water Pollutants, Chemical/chemistry
17.
Water Sci Technol ; 68(7): 1665-71, 2013.
Article in English | MEDLINE | ID: mdl-24135118

ABSTRACT

New and higher standards in the EU water framework directive necessitate advanced treatment of secondary effluents for reduction of trace organic compounds (TrOCs) and nutrients before the discharge into receiving surface waters. Due to its dual function as oxidant and coagulant, ferrate is considered as a promising alternative for tertiary treatment. The oxidation of selected TrOCs and simultaneous flocculation of phosphates by ferrate was tested in batch experiments with secondary effluent from Berlin Ruhleben. The concentrations of carbamazepine (CBZ) and diclofenac were reduced by >90% with ferrate dosages of 6 mg/L as Fe. CBZ was transformed to 1-(2-benzaldehyde)-4-hydro-(1H,3H)-quinazoline-2-one, which is known as the major product from the reaction of CBZ with ozone. In contrast to ozonation, no further transformation of this product was observed. The concentration of ibuprofen was not reduced by ferrate treatment. For efficient removal of 60-100 µg/L phosphate-P to values <20 µg/L, ferrate dosages of 3-4 mg/L as Fe were sufficient.


Subject(s)
Iron/chemistry , Waste Disposal, Fluid , Carbamazepine/chemistry , Germany , Molecular Structure , Oxidation-Reduction , Ozone , Water Pollutants, Chemical/chemistry , Water Purification
18.
Water Res ; 47(17): 6467-74, 2013 Nov 01.
Article in English | MEDLINE | ID: mdl-24050684

ABSTRACT

The application of the R(CT)-concept for predicting the removal of trace organic compounds (TrOCs) in organic rich WWTP effluents is often problematic due to the fast ozone depletion with instantaneous ozone demand in the range of typically applied ozone dosages. In this study, the determination of OH-radical and ozone exposure from second order rate kinetics with two internal tracer substances was evaluated as alternative approach for these waters. Results from batch and semi-batch experiments showed a linear correlation of OH-radical exposure with ozone consumption, characterized by its slope indicating the formation efficiency of OH-radicals and a lag ozone consumption without significant formation of OH-radicals. Evaluation of data from the project PILOTOX on ozonation of secondary effluent confirmed reasonable prediction of ozone resistant compound removal from relative residual concentration of an internal tracer substance. In contrast, predicting the reduction of TrOCs by direct reactions with ozone from internal tracers was not feasible. Similar removal efficiencies for fast reacting compounds with different rate constants from k(O3) = 10(4) M(-1) s(-1) to k(O3) = 10(6) M(-1) s(-1) were observed indicating a limitation of the reaction by mass transfer. This effect was observed at low ozone dosages in semi-batch and pilot experiments as well as in batch experiments, where mass transfer from gas to liquid phase is not limiting. It is assumed that consumption of low ozone dosages is faster than sample homogenization in the batch reactors used. Thus, prediction of compound removal by direct reaction with ozone always needs to consider reactor design and geometry.


Subject(s)
Organic Chemicals/isolation & purification , Ozone/chemistry , Waste Disposal, Fluid , Water Pollutants, Chemical/isolation & purification , Hydroxyl Radical , Ketoprofen/chemistry , Kinetics , Pilot Projects , Reproducibility of Results , Water Purification
19.
Methods Inf Med ; 52(4): 360-9, 2013.
Article in English | MEDLINE | ID: mdl-23877646

ABSTRACT

BACKGROUND: Continuous improvements of IT-performance in healthcare organisations require actionable performance indicators, regularly conducted, independent measurements and meaningful and scalable reference groups. Existing IT-benchmarking initiatives have focussed on the development of reliable and valid indicators, but less on the questions about how to implement an environment for conducting easily repeatable and scalable IT-benchmarks. OBJECTIVES: This study aims at developing and trialling a procedure that meets the afore-mentioned requirements. METHODS: We chose a well established, regularly conducted (inter-) national IT-survey of healthcare organisations (IT-Report Healthcare) as the environment and offered the participants of the 2011 survey (CIOs of hospitals) to enter a benchmark. The 61 structural and functional performance indicators covered among others the implementation status and integration of IT-systems and functions, global user satisfaction and the resources of the IT-department. Healthcare organisations were grouped by size and ownership. The benchmark results were made available electronically and feedback on the use of these results was requested after several months. RESULTS: Fifty-ninehospitals participated in the benchmarking. Reference groups consisted of up to 141 members depending on the number of beds (size) and the ownership (public vs. private). A total of 122 charts showing single indicator frequency views were sent to each participant. The evaluation showed that 94.1% of the CIOs who participated in the evaluation considered this benchmarking beneficial and reported that they would enter again. Based on the feedback of the participants we developed two additional views that provide a more consolidated picture. CONCLUSION: The results demonstrate that establishing an independent, easily repeatable and scalable IT-benchmarking procedure is possible and was deemed desirable. Based on these encouraging results a new benchmarking round which includes process indicators is currently conducted.


Subject(s)
Benchmarking/organization & administration , Delivery of Health Care/organization & administration , Electronic Health Records/organization & administration , Health Services Research/organization & administration , Medical Informatics Computing , Quality Indicators, Health Care/organization & administration , Germany , Hospital Administration/standards , Humans
20.
Phys Rev Lett ; 110(5): 053602, 2013 Feb 01.
Article in English | MEDLINE | ID: mdl-23414019

ABSTRACT

We demonstrate amplification of a microwave signal by a strongly driven two-level system in a coplanar waveguide resonator. The effect, similar to the dressed-state lasing known from quantum optics, is observed with a single quantum system formed by a persistent current (flux) qubit. The transmission through the resonator is enhanced when the Rabi frequency of the driven qubit is tuned into resonance with one of the resonator modes. Amplification as well as linewidth narrowing of a weak probe signal has been observed. The stimulated emission in the resonator has been studied by measuring the emission spectrum. We analyzed our system and found an excellent agreement between the experimental results and the theoretical predictions obtained in the dressed-state model.

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