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Biomedical subjects

E Melin

Publications and source records attributed to E Melin.

10 recordsLinked to original sources

Effect of organic loading rate on a wastewater treatment process combining moving bed biofilm and membrane reactors.

The effect of moving bed biofilm reactor (MBBR) loading rate on membrane fouling rate was studied in two parallel units combining MBBR and membrane reactor. Hollow fiber membranes with molecular weight cut-off of 30 kD were used. The HRTs of the MBBRs varied from 45 min to 4 h and the COD loading rates ranged from 4.1 to 26.6 g COD m(-2) d(-1). The trans-membrane pressure (TMP) was very sensitive to fluxes for the used membranes and the experiments were carried out at relatively low fluxes (3.3-5.6 l m(-2) h(-1)). Beside the test with the highest flux, there were no consistent differences in fouling rate between the low- and high-rate reactors. Also, the removal efficiencies were quite similar in both systems. The average COD removal efficiencies in the total process were 87% at 3-4 h HRT and 83% at 0.75-1 h HRT. At high loading rates, there was a shift in particle size distribution towards smaller particles in the MBBR effluents. However, 79-81% of the COD was in particles that were separated by membranes, explaining the relatively small differences in the removal efficiencies at different loading rates. The COD fractionation also indicated that the choice of membrane pore size within the range of 30 kD to 0.1 microm has very small effect on the COD removal in the MBBR/membrane process, especially with low-rate MBBRs.

Biofilms↗

High-rate wastewater treatment combining a moving bed biofilm reactor and enhanced particle separation.

Many cities around the world are looking for compact wastewater treatment alternatives since space for treatment plants is becoming scarce. In this paper development of a new compact, high-rate treatment concept with results from experiments in lab-scale and pilot-scale are presented. The idea behind the treatment concept is that coagulation/floc separation may be used to separate suspended and colloidal matter (resulting in > 70% organic matter removal in normal wastewater) while a high-rate biofilm process (based on Moving Bed biofilm reactors) may be used for removing low molecular weight, easily biodegradable, soluble organic matter. By using flotation for floc/biomass separation, the total residence time for a plant according to this concept will normally be < 1 hour. A cationic polymer combined with iron is used as coagulant at low dosages (i.e. 1-2 mg polymer/l, 5-10 mg Fe/l) resulting in low sludge production (compared to conventional chemical treatment) and sufficient P-removal.

Biofilms↗

Nurse-patient interaction after training in integrity promoting care at a long-term ward: analysis of video-recorded morning care sessions.

Morning care is a complex and problematic task for the demented patient, who has problems in understanding and coping with the situation. A training programme of integrity promoting care was given to the staff of a long-term ward and improvements of care were implemented during a 3 month intervention period. To evaluate possible effects, different parameters were used and compared with the data of a control ward. This report describes how caregivers behaved towards demented patients during morning care, before and after the training, and how patients' behaviour changed. The results are based on behaviour samples from 10 patients and 10 caregivers during 99 video-recorded morning care sessions, "double blindly" analysed. The number of coding schemes was 483, each consisting of 93 questions. The most prominent differences observed after the intervention were the increased number of opportunities to take part in decisions and activities given to the patients by the caregivers, more co-operation from patients, and finally an increase in verbal contact initiated both by patients and caregivers. It seems reasonable to suggest that when the environment was made more adequate and the demented patients could cope with it, they could use latent abilities that were not manifest in a less adequate environment.

Activities of Daily Living↗

Biochemical indicators of hazardous shoulder-neck loads in light industry.

Prolonged, repetitive handling of light material is known to increase the risk of shoulder-neck disorders. Biological risk indicators related to musculoskeletal exposure, applicable by the general practitioner in the workplace, could provide an instrument for early intervention and rehabilitation. Eight women were studied, all full-time workers performing assembly tasks associated with a high prevalence of shoulder-neck complaints. All subjects were more tender in the shoulder region than young women in low-risk occupations. Heart rate recordings indicated a low general metabolic load during work. Concentrations in antecubital venous blood of several markers for metabolic stress and cellular damage (lactate, ammonia, hypoxanthine, urate, malondialdehyde, potassium, creatine kinase) were normal for all subjects, and showed no increase during 3 consecutive working days. Thus, the blood markers did not reflect hazardous shoulder-neck exposure.

Adult↗

Effects of environmental stimulation on biochemical and psychological variables in dementia.

The nursing care of a group of moderately demented patients (n = 11) in a nursing home was improved as a result of an education of the staff. Thus the patients were subjected to an increased emotional and intellectual stimulation during the ordinary daily care and participated in group sessions twice a week. In order to evaluate the effects of the treatment, psychological parameters and cerebrospinal fluid (CSF) HVA (homovanillic acid), 5-HIAA (5-hydroxyindole acetic acid) and HMPG (4-hydroxy, 3-metoxyphenylglucol) were quantified before and after a 2-month treatment period. A group of similar patients (n = 13) in another nursing home constituted a control group. The ratings of concentration, absent mindedness and recent memory showed a more favorable development in the treatment group than in the control group where an intellectual deterioration was evident. Restlessness was rated higher in the treatment group after the treatment period, while the psychological testings showed no significant changes between the groups. CSF HVA concentrations increased in the treatment group and decreased in the control group (P less than 0.05). No change was evident in 5-HIAA or HMPG concentrations in either group. The results suggest that environmental factors influence biochemical markers of transmitter activity which thus possibly may be of etiological importance in dementia.

Aged↗

Reactions to music, touch and object presentation in the final stage of dementia. An exploratory study.

Two patients in the final stage of dementia of Alzheimer type were stimulated with music, touch and object presentation during 12 consecutive days (16 trials per patient). Evaluations were made by direct observations, analysis of video-taped recordings and registrations of pulse and rate of respiration. Both patients reacted differently to music than to touch and object presentation.

Aged↗