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1.
Semin Oncol Nurs ; 38(4): 151268, 2022 08.
Article in English | MEDLINE | ID: mdl-35527090

ABSTRACT

OBJECTIVES: In many countries, there is a lack of structured psychosocial health interventions to support young people with cancer. Thus, we developed the nurse-led intervention the Youth-Check Program with the aim of supporting young people with cancer. The aim of the study was to evaluate young patients with cancer and their parents' experiences of the program. DATA SOURCES: In total, 23 semi-structured interviews were conducted. Participants were young patients with cancer, aged 12-18 years (n = 10) and parents aged 41-53 years (n = 13). Data were analyzed thematically using Malterud's systematic text condensation. CONCLUSION: Three themes were derived: "The Youth-Check Program offers a safe space that led to openness among the young people," "participation in the Youth-Check Program met parents' needs for support for their teenager," and "the Youth-Check Program provided new insights that were not always taken into account." IMPLICATIONS FOR NURSING PRACTICE: The Youth-Check Program is a feasible and useful nurse-led intervention, which can be implemented for the benefit of young people with cancer. However, to strengthen the Youth-Check Program, it is important to define young people's individual needs to make sure they are met according to their specific preferences. Most young people took on more treatment responsibility, and they were empowered to set their own agenda in terms of what kind of support they needed in relation to topics that preoccupied them. The parents were given much needed support for their teenagers.


Subject(s)
Neoplasms , Psychosocial Intervention , Adolescent , Humans , Neoplasms/therapy , Parents/psychology
2.
Nurse Educ Pract ; 60: 103291, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35276406

ABSTRACT

The aim of this study is to explore and compare if evidence-based practice is reflected in topics and methods in the bachelor assignment written by respectively nursing and midwifery students. METHOD: The study is a document study; data is bachelor assignments (N = 274) from nursing (244) and midwifery (30) educations in Copenhagen in 2018. The abductive analysis examines the whole picture of used designs/methods, identify themes in the assignments and compare the assignments for similarities and differences. RESULTS: Nursing students mainly chose interview as a method, with 56% choosing to interview nurses and 17% choosing to interview patients. 90% of midwifery students chose to do literature studies. Nursing students mainly focus either on nurses' experience of clinical practise describing either personal or local nursing practice or on patient's experience (second person knowledge). Nursing students rarely employ evidence from research. Midwifery students employ knowledge from literature and mainly focus on professional action or discussion of the evidence in relation to professional practice. CONCLUSION: Midwifery students' bachelor assignments indicate an ability to understand and use evidence in planning for professional action, while the bachelor assignments of nursing students do not.


Subject(s)
Education, Nursing, Baccalaureate , Education, Nursing , Midwifery , Students, Nursing , Denmark , Education, Nursing, Baccalaureate/methods , Evidence-Based Practice , Female , Humans , Midwifery/education , Pregnancy
3.
Biosens Bioelectron ; 75: 375-82, 2016 Jan 15.
Article in English | MEDLINE | ID: mdl-26342573

ABSTRACT

Wastewater samples from a Swedish chemi-thermo-mechanical pulp (CTMP) mill collected at different purification stages in a wastewater treatment plant (WWTP) were analyzed with an amperometric enzyme-based biosensor array in a flow-injection system. In order to resolve the complex composition of the wastewater, the array consists of several sensing elements which yield a multidimensional response. We used principal component analysis (PCA) to decompose the array's responses, and found that wastewater with different degrees of pollution can be differentiated. With the help of partial least squares regression (PLS-R), we could link the sensor responses to the Microtox® toxicity parameter, as well as to global organic pollution parameters (COD, BOD, and TOC). From investigating the influences of individual sensors in the array, it was found that the best models were in most cases obtained when all sensors in the array were included in the PLS-R model. We find that fast simultaneous determination of several global environmental parameters characterizing wastewaters is possible with this kind of biosensor array, in particular because of the link between the sensor responses and the biological effect onto the ecosystem into which the wastewater would be released. In conjunction with multivariate data analysis tools, there is strong potential to reduce the total time until a result is yielded from days to a few minutes.


Subject(s)
Biosensing Techniques , Environmental Monitoring , Water Pollutants, Chemical/isolation & purification , Wastewater/chemistry , Water Pollutants, Chemical/chemistry
4.
Chemosphere ; 139: 240-5, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26142613

ABSTRACT

The nano-form of copper (Cu-NPs) is already extensively used. In this paper the toxic effect of Cu in the worm Enchytraeus crypticus (Oligochaeta: Enchytraeidae) was assessed following exposure to (1) Cu-salt: freshly spiked soil with copper-nitrate, (2) Cu-NPs: freshly spiked soil with Cu nanoparticles (80nm), and (3) Cu-field: historically Cu contaminated soil (80years ago). Our main aims were to compare the three different exposure regimes and respective toxicity, and to determine how the oxidation state of the Cu and dissolution state of the particles differed. Characterization of in situ-exposure included identification of oxidation states with synchrotron generated X-ray absorption near-edge spectroscopy (XANES) analysis, activity of free Cu(2+) in soil-solution (Ion Selective Electrode), and the relative distribution of the labile Cu-fractions (Sequential Extraction). Freshly spiked Cu-salt was the most toxic for reproductive output of the worms, followed by Cu-NPs and then Cu-field. XANES indicated only one oxidation state (II) in Cu-salt and Cu-field soil, whereas in Cu-NPs soil it was present in all oxidation states (0, I and II). The partial oxidation of the Cu-NPs (in soil) was evident and with limited dissolution.


Subject(s)
Copper/toxicity , Nanoparticles/chemistry , Nitrates/toxicity , Oligochaeta/drug effects , Soil Pollutants/toxicity , Soil/chemistry , Animals , Copper/analysis , Ecotoxicology , Nitrates/analysis , Soil Pollutants/analysis , Synchrotrons , X-Ray Absorption Spectroscopy
5.
PLoS One ; 10(3): e0121111, 2015.
Article in English | MEDLINE | ID: mdl-25812161

ABSTRACT

INTRODUCTION: Risk factors for breast milk transmission of HIV-1 from mother to child include high plasma and breast milk viral load, low maternal CD4 count and breast pathology such as mastitis. OBJECTIVE: To determine the impact of nevirapine and subclinical mastitis on HIV-1 RNA in maternal plasma and breast milk after intrapartum single-dose nevirapine combined with either 1-week tail of Combivir (zidovudine/lamivudine) or single-dose Truvada (tenofovir/emtricitabine). METHODS: Maternal plasma and bilateral breast milk samples were collected between April 2008 and April 2011 at 1, 4 and 6 weeks postpartum from HIV-infected Tanzanian women. Moreover, plasma samples were collected at delivery from mother and infant. RESULTS: HIV-1 RNA was quantified in 1,212 breast milk samples from 273 women. At delivery, 96% of the women and 99% of the infants had detectable nevirapine in plasma with a median (interquartile range, IQR) of 1.5 µg/mL (0.75-2.20 µg/mL) and 1.04 µg/mL (0.39-1.71 µg/mL), respectively (P < 0.001). At 1 week postpartum, 93% and 98% of the women had detectable nevirapine in plasma and breast milk, with a median (IQR) of 0.13 µg/mL (0.13-0.39 µg/mL) and 0.22 µg/mL (0.13-0.34 µg/mL), respectively. Maternal plasma and breast milk HIV-1 RNA correlated at all visits (R = 0.48, R = 0.7, R = 0.59; all P = 0.01). Subclinical mastitis was detected in 67% of the women at some time during 6 weeks, and in 38% of the breast milk samples. Breast milk samples with subclinical mastitis had significantly higher HIV-1 RNA at 1, 4 and 6 weeks (all P < 0.05). CONCLUSION: After short-course antiretroviral prophylaxis, nevirapine was detectable in most infant cord blood samples and the concentration in maternal plasma and breast milk was high through week 1 accompanied by suppressed HIV-1 RNA in plasma and breast milk.


Subject(s)
Anti-HIV Agents/pharmacokinetics , Antiretroviral Therapy, Highly Active , HIV Infections/drug therapy , HIV Infections/virology , HIV-1/genetics , Milk, Human/virology , Nevirapine/pharmacokinetics , Sodium , Adult , Anti-HIV Agents/administration & dosage , Female , HIV Infections/transmission , Humans , Infectious Disease Transmission, Vertical/prevention & control , Mastitis/epidemiology , Mastitis/etiology , Nevirapine/administration & dosage , Premedication , Prevalence , RNA, Viral , Viral Load , Young Adult
7.
Environ Sci Eur ; 26(1): 12, 2014.
Article in English | MEDLINE | ID: mdl-28936382

ABSTRACT

BACKGROUND: While the use of plastic materials has generated huge societal benefits, the 'plastic age' comes with downsides: One issue of emerging concern is the accumulation of plastics in the aquatic environment. Here, so-called microplastics (MP), fragments smaller than 5 mm, are of special concern because they can be ingested throughout the food web more readily than larger particles. Focusing on freshwater MP, we briefly review the state of the science to identify gaps of knowledge and deduce research needs. STATE OF THE SCIENCE: Environmental scientists started investigating marine (micro)plastics in the early 2000s. Today, a wealth of studies demonstrates that MP have ubiquitously permeated the marine ecosystem, including the polar regions and the deep sea. MP ingestion has been documented for an increasing number of marine species. However, to date, only few studies investigate their biological effects. The majority of marine plastics are considered to originate from land-based sources, including surface waters. Although they may be important transport pathways of MP, data from freshwater ecosystems is scarce. So far, only few studies provide evidence for the presence of MP in rivers and lakes. Data on MP uptake by freshwater invertebrates and fish is very limited. KNOWLEDGE GAPS: While the research on marine MP is more advanced, there are immense gaps of knowledge regarding freshwater MP. Data on their abundance is fragmentary for large and absent for small surface waters. Likewise, relevant sources and the environmental fate remain to be investigated. Data on the biological effects of MP in freshwater species is completely lacking. The accumulation of other freshwater contaminants on MP is of special interest because ingestion might increase the chemical exposure. Again, data is unavailable on this important issue. CONCLUSIONS: MP represent freshwater contaminants of emerging concern. However, to assess the environmental risk associated with MP, comprehensive data on their abundance, fate, sources, and biological effects in freshwater ecosystems are needed. Establishing such data critically depends on a collaborative effort by environmental scientists from diverse disciplines (chemistry, hydrology, ecotoxicology, etc.) and, unsurprisingly, on the allocation of sufficient public funding.

8.
Int J Risk Saf Med ; 25(3): 155-68, 2013.
Article in English | MEDLINE | ID: mdl-24047687

ABSTRACT

AIM: Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time. METHODS: Documentary study. We searched the web-sites of the European Medicines Agency and the drug agencies in USA, UK, and Denmark for documents mentioning benzodiazepines or SSRIs. We supplemented with other relevant literature that could contribute to our study. The searches were performed in 2009 in PubMed, Google, BMJ and JAMA. RESULTS: It took many years before the drug regulators acknowledged benzodiazepine dependence and SSRI withdrawal reactions and before the prescribers and the public were informed. Drug regulators relied mainly on the definitions of dependence and withdrawal reactions from the diagnostic psychiatric manuals, which contributed to the idea that SSRIs do not cause dependence, although it is difficult for many patients to stop treatment. In the perspective of a precautionary principle, drug agencies have failed to acknowledge that SSRIs can cause dependence and have minimised the problem with regard to its frequency and severity. In the perspective of a risk management principle, the drug agencies have reacted in concordance with the slowly growing knowledge of adverse drug reactions and have sharpened the information to the prescribers and the public over time. However, solely relying on spontaneous reporting of adverse effects leads to underestimation and delayed information about the problems. CONCLUSION: Given the experience with the benzodiazepines, we believe the regulatory bodies should have required studies from the manufacturers that could have elucidated the dependence potential of the SSRIs before marketing authorization was granted.


Subject(s)
Benzodiazepines/adverse effects , Selective Serotonin Reuptake Inhibitors/adverse effects , Substance Withdrawal Syndrome/etiology , Substance-Related Disorders/etiology , Benzodiazepines/history , European Union , History, 20th Century , Humans , Legislation, Drug , Selective Serotonin Reuptake Inhibitors/history , Substance Withdrawal Syndrome/history , Substance Withdrawal Syndrome/psychology , United States
10.
Addiction ; 107(5): 900-8, 2012 May.
Article in English | MEDLINE | ID: mdl-21992148

ABSTRACT

AIMS: To explore the rationale for claiming that benzodiazepines cause dependence while selective serotonin re-uptake inhibitors (SSRIs) do not. METHODS: We analysed the definitions of dependence and withdrawal reactions as they had appeared over time in the Diagnostic Statistical Manual of Mental Diseases (DSM) and the International Classification of Diseases (ICD). We also compared the discontinuation symptoms described for the two drug groups in a systematic review. RESULTS: The definition of substance dependence has changed over time in both the DSM and ICD. In the most recent classifications several criteria, including behavioural, physiological and cognitive manifestations, must be fulfilled. This change was published with the revision of the DSM-III revision in 1987 (DSM-IIIR), after the recognition of benzodiazepine dependence and just before the SSRIs were marketed in 1987-88. We found that discontinuation symptoms were described with similar terms for benzodiazepines and SSRIs and were very similar for 37 of 42 identified symptoms described as withdrawal reactions. CONCLUSIONS: Withdrawal reactions to selective serotonin re-uptake inhibitors appear to be similar to those for benzodiazepines; referring to these reactions as part of a dependence syndrome in the case of benzodiazepines, but not selective serotonin re-uptake inhibitors, does not seem rational.


Subject(s)
Benzodiazepines/adverse effects , Selective Serotonin Reuptake Inhibitors/adverse effects , Substance-Related Disorders/etiology , Diagnosis, Differential , Diagnostic and Statistical Manual of Mental Disorders , Humans , International Classification of Diseases , Substance Withdrawal Syndrome/diagnosis , Substance Withdrawal Syndrome/etiology , Substance-Related Disorders/diagnosis , World Health Organization
11.
J Med Virol ; 84(2): 183-7, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22170535

ABSTRACT

Detection of HIV-1 RNA in semen is used commonly to determine the safety of semen processing procedures before assisted reproductive technology (ART). Using two panels of prepared semen samples containing HIV-1 the performances of protocols from 14 centers have been compared. No false-positive results were detected but false-negative results were frequent when the concentration was below 500 HIV-1 RNA copies/ml of seminal plasma. Frequency of HIV-1 RNA detection was higher on seminal cells than on seminal plasma. Assays (or protocols) for quantifying HIV-1 RNA in semen performed less well than standardized blood plasma assays. The HIV load in seminal plasma could be a useful marker of the risk of sexual transmission of the virus. Its use as a marker of global HAART efficiency in the HIV reservoir needs further study. Standardized assays are required for detection and measurement of HIV-1 RNA in semen samples.


Subject(s)
HIV-1/genetics , RNA, Viral/analysis , Semen/virology , HIV Infections/transmission , HIV Infections/virology , HIV Seropositivity/virology , Humans , Male , Quality Control , Reproductive Techniques, Assisted , Sensitivity and Specificity , Viral Load
12.
Int J Risk Saf Med ; 23(2): 125-32, 2011.
Article in English | MEDLINE | ID: mdl-21673422

ABSTRACT

BACKGROUND: Prescribing of selective serotonin reuptake inhibitors (SSRIs) has increased dramatically. OBJECTIVE: To compare the sales of benzodiazepines and SSRIs within the primary care sector in Denmark and relate changes in usage to number of indications and products on the market. METHODS: We used data from various sources to establish the sales curves of psychotropic drugs in the period 1970 to 2007, based on the Anatomic Therapeutic Classification system and Defined Daily Doses. RESULTS: Fluctuations in sales of psychotropic drugs that cannot be explained by disease prevalence were caused by changes in sales of the benzodiazepines and SSRIs. We found a decline in the sales of benzodiazepines after a peak in 1986, likely due to the recognition that they cause dependence. From a low level in 1992, we found that the sales of SSRIs increased almost linearly by a factor of 18, up to 44 DDD per 1000 inhabitants, which was closely related to the number of products on the market that increased by a factor of 16. CONCLUSIONS: Sales of antidepressant drugs are mainly determined by market availability of products indicating that marketing pressures are playing an important role. Thus the current level of use of SSRIs may not be evidence-based, which is supported by studies showing that the effect of SSRIs has been overestimated.


Subject(s)
Drug Prescriptions , Drug Utilization , Psychotropic Drugs/economics , Selective Serotonin Reuptake Inhibitors/economics , Antidepressive Agents/economics , Benzodiazepines/economics , Commerce , Denmark , Drug Prescriptions/economics , Drug Prescriptions/statistics & numerical data , Drug Utilization/economics , Drug Utilization/statistics & numerical data , Economics, Pharmaceutical , Humans , Inappropriate Prescribing/economics , Marketing , Primary Health Care/statistics & numerical data
13.
Cochrane Database Syst Rev ; (1): CD001877, 2011 Jan 19.
Article in English | MEDLINE | ID: mdl-21249649

ABSTRACT

BACKGROUND: A variety of estimates of the benefits and harms of mammographic screening for breast cancer have been published and national policies vary. OBJECTIVES: To assess the effect of screening for breast cancer with mammography on mortality and morbidity. SEARCH STRATEGY: We searched PubMed (November 2008). SELECTION CRITERIA: Randomised trials comparing mammographic screening with no mammographic screening. DATA COLLECTION AND ANALYSIS: Both authors independently extracted data. Study authors were contacted for additional information. MAIN RESULTS: Eight eligible trials were identified. We excluded a biased trial and included 600,000 women in the analyses. Three trials with adequate randomisation did not show a significant reduction in breast cancer mortality at 13 years (relative risk (RR) 0.90, 95% confidence interval (CI) 0.79 to 1.02); four trials with suboptimal randomisation showed a significant reduction in breast cancer mortality with an RR of 0.75 (95% CI 0.67 to 0.83). The RR for all seven trials combined was 0.81 (95% CI 0.74 to 0.87). We found that breast cancer mortality was an unreliable outcome that was biased in favour of screening, mainly because of differential misclassification of cause of death. The trials with adequate randomisation did not find an effect of screening on cancer mortality, including breast cancer, after 10 years (RR 1.02, 95% CI 0.95 to 1.10) or on all-cause mortality after 13 years (RR 0.99, 95% CI 0.95 to 1.03).Numbers of lumpectomies and mastectomies were significantly larger in the screened groups (RR 1.31, 95% CI 1.22 to 1.42) for the two adequately randomised trials that measured this outcome; the use of radiotherapy was similarly increased. AUTHORS' CONCLUSIONS: Screening is likely to reduce breast cancer mortality. As the effect was lowest in the adequately randomised trials, a reasonable estimate is a 15% reduction corresponding to an absolute risk reduction of 0.05%. Screening led to 30% overdiagnosis and overtreatment, or an absolute risk increase of 0.5%. This means that for every 2000 women invited for screening throughout 10 years, one will have her life prolonged and 10 healthy women, who would not have been diagnosed if there had not been screening, will be treated unnecessarily. Furthermore, more than 200 women will experience important psychological distress for many months because of false positive findings. It is thus not clear whether screening does more good than harm. To help ensure that the women are fully informed of both benefits and harms before they decide whether or not to attend screening, we have written an evidence-based leaflet for lay people that is available in several languages on www.cochrane.dk.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/mortality , Mammography , Mass Screening , Adult , Cause of Death , Diagnostic Errors , Female , Humans , Mammography/adverse effects , Mammography/psychology , Middle Aged , Randomized Controlled Trials as Topic , Risk
14.
Cochrane Database Syst Rev ; (4): CD001877, 2009 Oct 07.
Article in English | MEDLINE | ID: mdl-19821284

ABSTRACT

BACKGROUND: A variety of estimates of the benefits and harms of mammographic screening for breast cancer have been published and national policies vary. OBJECTIVES: To assess the effect of screening for breast cancer with mammography on mortality and morbidity. SEARCH STRATEGY: We searched PubMed (November 2008). SELECTION CRITERIA: Randomised trials comparing mammographic screening with no mammographic screening. DATA COLLECTION AND ANALYSIS: Both authors independently extracted data. Study authors were contacted for additional information. MAIN RESULTS: Eight eligible trials were identified. We excluded a biased trial and included 600,000 women in the analyses. Three trials with adequate randomisation did not show a significant reduction in breast cancer mortality at 13 years (relative risk (RR) 0.90, 95% confidence interval (CI) 0.79 to 1.02); four trials with suboptimal randomisation showed a significant reduction in breast cancer mortality with an RR of 0.75 (95% CI 0.67 to 0.83). The RR for all seven trials combined was 0.81 (95% CI 0.74 to 0.87). We found that breast cancer mortality was an unreliable outcome that was biased in favour of screening, mainly because of differential misclassification of cause of death. The trials with adequate randomisation did not find an effect of screening on cancer mortality, including breast cancer, after 10 years (RR 1.02, 95% CI 0.95 to 1.10) or on all-cause mortality after 13 years (RR 0.99, 95% CI 0.95 to 1.03).Numbers of lumpectomies and mastectomies were significantly larger in the screened groups (RR 1.31, 95% CI 1.22 to 1.42) for the two adequately randomised trials that measured this outcome; the use of radiotherapy was similarly increased. AUTHORS' CONCLUSIONS: Screening is likely to reduce breast cancer mortality. As the effect was lowest in the adequately randomised trials, a reasonable estimate is a 15% reduction corresponding to an absolute risk reduction of 0.05%. Screening led to 30% overdiagnosis and overtreatment, or an absolute risk increase of 0.5%. This means that for every 2000 women invited for screening throughout 10 years, one will have her life prolonged and 10 healthy women, who would not have been diagnosed if there had not been screening, will be treated unnecessarily. Furthermore, more than 200 women will experience important psychological distress for many months because of false positive findings. It is thus not clear whether screening does more good than harm. To help ensure that the women are fully informed of both benefits and harms before they decide whether or not to attend screening, we have written an evidence-based leaflet for lay people that is available in several languages on www.cochrane.dk.


Subject(s)
Breast Neoplasms/diagnostic imaging , Breast Neoplasms/mortality , Mammography , Mass Screening , Adult , Cause of Death , Diagnostic Errors , Female , Humans , Mammography/adverse effects , Mammography/psychology , Middle Aged , Randomized Controlled Trials as Topic
17.
J Acquir Immune Defic Syndr ; 48(3): 345-9, 2008 Jul 01.
Article in English | MEDLINE | ID: mdl-18545150

ABSTRACT

BACKGROUND: Implementation of antiretroviral treatment in sub-Saharan Africa requires efficient tools to monitor HIV patients. p24 measurements have been proposed as an alternative to HIV-RNA because of the low cost of reagents and equipment needed. Here, we evaluate p24 as a prognostic marker in a cohort of HIV-1-infected individuals in Zimbabwe. METHODS: Treatment-naive HIV-1-infected individuals (n=198) from the Mupfure Schistosomiasis and HIV Cohort were followed until death or censoring (3-4.3 years). At baseline, p24, HIV-RNA, CD4 cell counts, and clinical staging (Centers for Disease Control and Prevention classification) were assessed. RESULTS: p24 correlated with HIV-RNA (P<0.0001, R: 0.44). Ten percent of p24 but only 1% of HIV-RNA measurements was undetectable. p24 predicted Centers for Disease Control and Prevention category (P<0.001) stronger than CD4 count (P=0.34) in multivariate logistic regression. p24 predicted mortality in univariate Cox analysis (P<0.0001) and in multivariate analysis, but it was inferior to HIV-RNA and CD4 count. CONCLUSIONS: This is the first study to evaluate the prognostic strength of p24 in an area with a predominance of HIV subtype C infections. p24 correlated with HIV-RNA and predicted clinical stage better than CD4 count. It predicted mortality in both univariate and multivariate analysis, but in multivariate analysis, it was inferior to HIV-RNA and CD4 count.


Subject(s)
HIV Core Protein p24/analysis , HIV Infections/mortality , HIV-1/metabolism , Acquired Immunodeficiency Syndrome , Adult , Biomarkers/analysis , CD4 Lymphocyte Count , HIV-1/genetics , Humans , Predictive Value of Tests , Prognosis , RNA, Viral , Survival Analysis , Zimbabwe
19.
Biosens Bioelectron ; 21(4): 608-17, 2005 Oct 15.
Article in English | MEDLINE | ID: mdl-16202874

ABSTRACT

Four wastewater samples of different treatment qualities; untreated, alarm, alert and normal, from a Swedish chemi-thermo-mechanical pulp mill and pure water were investigated using an amperometric bio-electronic tongue in a batch cell. The aim was to explore enzymatically modified screen-printed amperometric sensors for the discrimination of wastewater quality and to counteract the inherent drift. Seven out of eight platinum electrodes on the array were modified with four different enzymes; tyrosinase, horseradish peroxidase, acetyl cholinesterase and butyryl cholinesterase. At a constant potential the current intensity on each sensor was measured for 200s, 100s before injection and 100s after injection of the sample. The dynamic biosensor response curves from the eight sensors were used for principal component analysis (PCA). A simple baseline and sensitivity correction equivalent to multiplicative drift correction (MDC), using steady state intensities of reference sample (catechol) recordings, was employed. A clear pattern emerged in perfect agreement with prior knowledge of the samples explaining 97% of the variation in the data by two principal components (PCs). The first PC described the treatment quality of the samples and the second PC described the difference between treated and untreated samples. Horseradish peroxidase and pure platinum sensors were found to be the determinant sensors, while the rest did not contribute much to the discrimination. The wastewater samples were characterized by the chemical oxygen demand (COD), biological oxygen demand (BOD), total organic carbon (TOC), inhibition of nitrification, inhibition of respiration and toxicity towards Vibrio fischeri using Microtox, the freshwater alga Pseudokirchneriella subcapita and the freshwater crustacean Daphnia magna.


Subject(s)
Biosensing Techniques/instrumentation , Combinatorial Chemistry Techniques/methods , Electrochemistry/instrumentation , Environmental Monitoring/instrumentation , Enzymes, Immobilized/chemistry , Industrial Waste/analysis , Water Pollutants/analysis , Algorithms , Biosensing Techniques/methods , Combinatorial Chemistry Techniques/instrumentation , Computer Systems , Electrochemistry/methods , Environmental Monitoring/methods , Equipment Design , Equipment Failure Analysis , Principal Component Analysis , Reproducibility of Results , Sensitivity and Specificity
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