Dissolved effluent organic matter: Characteristics and potential implications in wastewater treatment and reuse applications.

Wastewater reuse is currently considered globally as the most critical element of sustainable water management. The dissolved effluent organic matter (dEfOM) present in biologically treated urban wastewater, consists of a heterogeneous mixture of refractory organic compounds with diverse structures and varying origin, including dissolved natural organic matter, soluble microbial products, endocrine disrupting compounds, pharmaceuticals and personal care products residues, disinfection by-products, metabolites/transformation products and others, which can reach the aquatic environment through discharge and reuse applications. dEfOM constitutes the major fraction of the effluent organic matter (EfOM) and due to its chemical complexity, it is necessary to utilize a battery of complementary techniques to adequately describe its structural and functional character. dEfOM has been shown to exhibit contrasting effects towards various aquatic organisms. It decreases metal uptake, thus potentially reducing their bioavailability to exposed organisms. On the other hand, dEfOM can be adsorbed on cell membranes inducing toxic effects. This review paper evaluates the performance of various advanced treatment processes (i.e., membrane filtration and separation processes, activated carbon adsorption, ion-exchange resin process, and advanced chemical oxidation processes) in removing dEfOM from wastewater effluents. In general, the literature findings reveal that dEfOM removal by advanced treatment processes depends on the type and the amount of organic compounds present in the aqueous matrix, as well as the operational parameters and the removal mechanisms taking place during the application of each treatment technology.

Concentrations and mass loadings of hormones, alkylphenols, and alkylphenol ethoxylates in healthcare facility wastewaters.

Healthcare facility wastewaters are an anticipated source of known endocrine disrupting chemicals to the environment. In this study, the composition and magnitude of eight steroid hormones, octylphenol (OP), nonylphenol (NP), 16 nonylphenol ethoxylates (NPEOs), and 10 octylphenol ethoxylates (OPEOs) in wastewater from a(n) hospital, nursing facility, assisted living facility, and independent living facility are presented. Steroid hormone concentrations were variable for each sampling location, ranging from a non-detectable concentration of 17beta-ethynylestradiol in all samples to 127ngL(-1) androstenedione in the hospital's wastewater composite. OP and NP were not detected in any site's samples. However, NPEOs were found at each sampling location with a maximum combined concentration of 260microgL(-1) for NPEOs with a chain length between 3 and 18 units in the assisted living facility composite sample. OPEOs were only found in the hospital and nursing facilities samples with a maximum combined OPEO concentration of 13microgL(-1) for OPEOs with a chain length between 2 and 12 units in hospital wastewater. The total mass loading of hormones to the municipal sewer system from each facility ranged from 2.5mgd(-1) at the assisted living facility to 138mgd(-1) at the hospital. The total mass loading of the alklyphenol ethoxylates (NPEO+OPEO) is considerably higher than the estimated hormone mass loadings, ranging from 1.8gd(-1) at the independent living facility to 54gd(-1) at the hospital facility.

Deficiency of the syntrophins and alpha-dystrobrevin in patients with inherited myopathy.

The syntrophins and dystrobrevins are members of the dystrophin-associated protein complex, and are thought to function as modular adaptors for signalling proteins recruited to the sarcolemmal membrane. We have characterised the expression of the syntrophins (alpha-, beta1-, and beta2-) and alpha-dystrobrevin by immunohistochemistry in normal human muscle and in biopsies from 162 patients with myopathies of unknown aetiology (with normal staining for dystrophin and other dystrophin-associated proteins). Unlike mice, beta2-syntrophin is expressed at the sarcolemma in post-natal human skeletal muscle. Deficiency of alpha-dystrobrevin +/- beta2-syntrophin was present in 16/162 (10%) patients, compared to age-matched controls. All patients presented with congenital-onset hypotonia and weakness, although there was variability in clinical severity. Two major clinical patterns emerged: patients with deficiency of beta2-syntrophin and alpha-dystrobrevin presented with severe congenital weakness and died in the first year of life, and two patients with deficiency of alpha-dystrobrevin had congenital muscular dystrophy with complete external ophthalmoplegia. We have sequenced the coding regions of alpha-dystrobrevin and beta2-syntrophin in these patients, and identified a new isoform of dystrobrevin, but have not identified any mutations. This suggests that disease causing mutations occur outside the coding region of these genes, in gene(s) encoding other components of the syntrophin-dystrobrevin subcomplex, or in gene(s) responsible for their post-translational modification and normal localisation.

Improving heart failure care in the office setting.

This column is the sixth in a series describing Health Care Financing Administration (HCFA) initiatives to improve care for Medicare beneficiaries with heart failure. The fourth column addressed the Heart Failure Practice Improvement Effort, HCFA's pilot project to test the feasibility of assessing and improving heart failure care in the outpatient setting through the activities of HCFA-contracted peer review organizations in eight states. This column is dedicated to illustrating the progress of the Heart Failure Practice Improvement Effort project at an individual state and practice level, focusing on the quality improvement activities in outpatient heart failure care conducted by the Colorado peer review organization. (c)2001 CHF, Inc.

Nostalgic memories in dementia--a case study.

The literature indicates that some moderately to severely demented elderly people can still recall their emotionally subjective past. Emotion and cognition have a relationship that can be clearly seen in the recall of nostalgic memories. This article outlines a case study that illustrates how emotional autobiographical memories of past events can be stimulated through the individual use of reminiscence and counseling skills. The authors suggest that there are possible therapeutic effects attached to this approach and that this is an area worthy of further investigation.

Kinetics of dithionite reduction of the heme nonapeptide of cytochrome c.

The kinetics of dithionite reduction of the oxidized heme nonapeptide fragment of horse heart cytochrome c have been measured as a function of ionic strength at pH 7 and pH 9 by the stopped-flow technique. Dithionite concentration dependences indicate that the radical anion monomer, SO2-., is the active reductant. The pH 7 ionic strength dependence suggests that the heme peptide is reacting as a negatively charged molecule (its overall charge is calculated to be -1). Comparison of these results with the known rate of dithionite reduction of cytochrome c indicates that the heme nonapeptide has substantially greater inherent reactivity than cytochrome c, perhaps due to the greater accessibility of the heme.