Adsorbent obtained from CEPT sludge in wastewater chemically enhanced treatment.

Chemically enhanced primary treatment (CEPT) in municipal wastewater treatment is particularly suitable for rapidly growing cities. The focus on CEPT process now might be the cost of chemicals and disposal of chemical sludge. In this study, the potential application of adsorbent made from CEPT sludge in CEPT wastewater treatment was investigated in various conditions, such as the adsorbent dosage, pH, and dosing modes of ferric chloride and adsorbent. It was found that sludge-derived adsorbent was a good way of sludge disposal while enhanced pollutants removal rate and reduced the fresh ferric chloride dosage. With the use of 10.0 mg L(-1) of ferric chloride and 0.6 g L(-1) of the adsorbent at the first stage simultaneously, the enhanced removal efficiencies of turbidity, UV254, COD, TP were 83.3%, 52.3%, 48.8% and 89.0%, respectively. The experiments showed that ferric chloride dose was reduced about 50%. The pH played a significant role in coagulation and adsorption process.

[Frequency-specific responses of human brain to peripheral transcutaneous electric nerve stimulation: a functional magnetic resonance imaging study].

The purpose of the present investigation was to determine the responses of human brain to transcutaneous electric nerve stimulation (TENS) at different frequencies by functional magnetic resonance imaging (fMRI) examinations covering the whole brain of eleven healthy volunteers. Each subject received TENS at acupoints ST36 and SP6 of the left leg at the frequencies of 2 and 100 Hz. Frequency-specific responses were found in motor-related areas, thalamus, limbic system and associated cortex to stimulation of the two frequencies, while the primary somatosensory areas were activated by both. Therefore, it appears that 2 and 100 Hz TENS act through different neuro-pathways in the central nervous system.

[Progress in the study of pain by brain imaging].

This review deals with the recent functional brain imaging studies of pain. In summary, the sensory-discriminative component of pain is related with the lateral thalamus, primary and secondary somatosensory area and insular cortices, while the posterior parietal and prefrontal cortices seem to play a role in the cognitive-attentional process of nociceptive information. Different parts of anterior cingulate gyrus are correlated with cognitive and emotional aspects of pain. Brain imaging data obtained from clinical patients suffering from various kinds of pain especially neuropathic pain, were discussed at the end of this article.