Transformation of jarosite during simulated remediation of a sandy sulfuric soil.

Aeration of wetland soils containing iron (Fe) sulfides can cause strong acidification due to the generation of large amounts of sulfuric acid and formation of Fe oxyhydroxy sulfate phases such as jarosite. Remediation by re-establishment of anoxic conditions promotes jarosite transformation to Fe oxyhydroxides and/or Fe sulfides, but the driving conditions and mechanisms are largely unresolved. We investigated a sandy, jarosite-containing soil (initial pH = 3.0, Eh ~600 mV) in a laboratory incubation experiment under submerged conditions, either with or without wheat straw addition. Additionally, a model soil composed of synthesized jarosite mixed with quartz sand was used. Eh and pH values were monitored weekly. Solution concentrations of total dissolved organic carbon, Fe, S, and K as well as proportions of Fe2+ and SO42- were analysed at the end of the experiment. Sequential Fe extraction, X-ray diffraction, and Mössbauer spectroscopy were used to characterize the mineral composition of the soils. Only when straw was added to natural and artificial sulfuric soils, the pH increased up to 6.5, and Eh decreased to approx. 0 mV. The release of Fe (mainly Fe2+), K, and S (mainly SO42-) into the soil solution indicated redox- and pH-induced dissolution of jarosite. Mineralogical analyses confirmed jarosite losses in both soils. While lepidocrocite formed in the natural sulfuric soil, goethite was formed in the artificial sulfuric soil. Both soils showed also increases in non-sulfidized, probably organically associated Fe2+/Fe3+, but no (re-)formation of Fe sulfides. Unlike Fe sulfides, the formed Fe oxyhydroxides are not prone to support re-acidification in the case of future aeration. Thus, inducing moderately reductive conditions by controlled supply of organic matter could be a promising way for remediation of soils and sediments acidified by oxidation of sulfuric materials.

Behavior profiles in children with functional urinary incontinence before and after incontinence treatment.

OBJECTIVE: The purpose of this work was to analyze prospectively the prevalence of behavioral disorders in children with urinary incontinence because of nonneuropathic bladder-sphincter dysfunction before and after treatment for incontinence. METHODS: A total of 202 children with nonneuropathic bladder-sphincter dysfunction were enrolled in the European Bladder Dysfunction Study, in branches for urge syndrome (branch 1) and dysfunctional voiding (branch 2); 188 filled out Achenbach's Child Behavior Checklist before treatment and 111 after treatment. Child Behavior Checklist scales for total behavior problems were used along with subscales for externalizing problems and internalizing problems. RESULTS: After European Bladder Dysfunction Study treatment, the total behavior problem score dropped from 19% to 11%, the same prevalence as in the normative population; in branch 1 the score dropped from 14% to 13%, and in branch 2 it dropped from 23% to 8%. The prevalence of externalizing problems dropped too, from 12% to 8%: in branch 1 it was unchanged at 10%, and in branch 2 it dropped from 14% to 7%. The decrease in prevalence of internalizing problems after treatment, from 16% to 14%, was not significant. CONCLUSION: More behavioral problems were found in dysfunctional voiding than in urge syndrome, but none of the abnormal scores related to the outcome of European Bladder Dysfunction Study treatment for incontinence. With such treatment, both the total behavior problem score and the score for externalizing problems returned to normal, but the score for internalizing problems did not change. The drops in prevalence are statistically significant only in dysfunctional voiding.

Self-reported urinary incontinence, voiding frequency, voided volume and pad-test results: variables in a prospective study in children.

OBJECTIVE: To determine the congruence between self-reported and objective data on incontinence, voided volume (VV) and voiding frequency (VF), in a prospective study of treatment of functional urinary incontinence (UI) due to urge syndrome or dysfunctional voiding in children. PATIENTS AND METHODS: In all, 202 children, enrolled in the European Bladder Dysfunction Study (EBDS), provided self-reported data on UI, VV and VF, before and after treatment, with validated questionnaires and 72-h voiding diaries. Objective data were obtained with uroflowmetry and a 12-h pad test, also before and after treatment. Questionnaires and diaries were checked and scored by a urotherapist, at scheduled office visits that were combined with uroflowmetry. RESULTS: At entry, parents under-reported UI on the questionnaires in 45% of cases, compared with the urotherapist's scores, and the 12-h pad test sensitivity for UI was only 64% (95% confidence interval 55-73%). The voiding diaries had inconsistent entries on UI and on VV. VF was overestimated in the questionnaires and underestimated in the diaries, compared with the urotherapist's scores. A VF of >7/day decreased significantly after EBDS treatment, but with no correlation with treatment outcome. The mean VV increased significantly after treatment for UI, also with no correlation with treatment outcome. CONCLUSIONS: Voiding diaries and questionnaires are useful tools for charting individual treatment and for screening, but they are ill-suited to documenting outcome variables in urge syndrome or dysfunctional voiding, because of over- and under-reporting. VV and VF lack specificity as outcome variables in children with urge syndrome or dysfunctional voiding. The 12-h pad test is not sensitive enough to complement self-reported symptoms of UI in children with urge syndrome or dysfunctional voiding. Clinical studies on UI rely on complaints and self-reported symptoms, but in children the reporting should be supervised by a trained urotherapist, to provide the necessary checks and balances.

Home uroflowmetry biofeedback in behavioral training for dysfunctional voiding in school-age children: a randomized controlled study.

PURPOSE: We studied the added value of home uroflowmetry for biofeedback training compared to added attention and standard therapy in a multicomponent behavioral training program for voiding disorders in school-age children. Little is known about the role of biofeedback by home uroflowmetry for dysfunctional voiding due to NNBSD in children. MATERIALS AND METHODS: A randomized controlled study was conducted at an outpatient pediatric incontinence university clinic from January 2000 to June 2003. A total of 192 children 6 to 16 years old who were suffering from recurrent urinary tract infections with or without urge incontinence were screened for NNBSD. Of 143 eligible patients 44 were randomly allocated to receive 8 weeks of standard therapy (outpatient behavioral therapy), 46 to receive 8 weeks of home video instructions together with standard therapy and 53 to receive 8 weeks of home uroflowmetry biofeedback together with standard therapy. After 8 weeks all treatment groups proceeded with standard therapy for 16 weeks, after which prophylaxis with antibiotics was stopped and patients were followed for another 6 months. Main outcome measurement was total relief of complaints, namely urinary tract infections and, if present, incontinence, at 12 months after randomization. RESULTS: At baseline there was no reason to predict major incomparabilities between the groups. In an intent to treat analysis there was no difference in total relief between standard treatment (44%) and added video instruction (42%, RR 0.96, 95% CI 0.59 to 1.56). Total relief in the added home uroflowmetry group (55%) was higher than with standard therapy (RR 1.24, 95% CI 0.80 to 1.93), although the difference was not statistically significant. A per protocol analysis suggested that the groups with added home uroflowmetry showed better total relief than the pooled groups with standard therapy and those with added video (RR 1.40, 95% CI 0.98 to 2.00). CONCLUSIONS: Home uroflowmetry appears to be a useful adjunctive treatment for the reduction of complaints in children with dysfunctional voiding due to nonneurogenic bladder-sphincter dyssynergia.