Efficient treatment of veterinary pharmaceutical industrial wastewater by catalytic ozonation process: degradation of enrofloxacin via molecular ozone reactions

The study focused on the efficacious performance of bimetallic Fe-Zn loaded 3A zeolite in catalytic ozonation for the degradation of highly toxic veterinary antibiotic enrofloxacin in wastewater of the pharmaceutical industry. Batch experiments were conducted in a glass reactor containing a submerged pump holding catalyst pellets at suction. The submerged pump provided the agitation and recirculation across the solution for effective contact with the catalyst. The effect of ozone flow (0.8-1.55 mg/min) and catalyst dose (5-15 g/L) on the enrofloxacin degradation and removal of other conventional pollutants COD, BOD5, turbidity was studied. In batch experiments, 10 g of Fe-Zn 3A zeolite efficiently removed 92% of enrofloxacin, 77% of COD, 69% BOD5, and 61% turbidity in 1 L sample of pharmaceutical wastewater in 30 min at 1.1 mg/min of O3 flow. The catalytic performance of Fe-Zn 3A zeolite notably exceeded the removal efficiencies of 52%, 51%, 52%, and 59% for enrofloxacin, COD, BOD5, and turbidity, respectively, achieved with single ozonation process. Furthermore, an increase in the biodegradability of treated pharmaceutical industrial wastewater was observed and made biodegradable easily for subsequent treatment.

Removal of copper from water using limestone filtration technique. Determination of mechanism of removal

This paper discusses heavy metal removal from wastewater by batch study and filtration technique through low-cost coarse media. Batch study has indicated that more than 90% copper (Cu) with concentration up to 50 mg/l could be removed from the solution with limestone quantity above 20 ml (equivalent to 56 g), which indicates the importance of limestone media in the removal process. This indicates that the removal of Cu is influenced by the media and not solely by the pH. Batch experiments using limestone and activated carbon indicate that both limestone and activated carbon had similar metal-removal efficiency (about 95%). Results of the laboratory-scale filtration technique using limestone particles indicated that above 90% removal of Cu was achieved at retention time of 2.31 h, surface-loading rate of 4.07 m3/m2 per day and Cu loading of 0.02 kg/m3 per day. Analyses of the limestone media after filtration indicated that adsorption and absorption processes were among the mechanisms involved in the removal processes. This study indicated that limestone can be used as an alternative to replace activated carbon.

Interpretative reporting and selective antimicrobial susceptibility release in non-critical microbiology results

The action taken in response to 169 positive sputum, urine and wound culture reports was examined. All reports included interpretative comments. Antimicrobial susceptibilities were released in 29 (17%). Therapy was significantly more likely to be started or altered in response to reports where susceptibilities were released (13 of 29, 45%) versus those without susceptibility release (31 of 140, 22%). Susceptibility release did not influence the appropriateness of antibiotic therapy. The clinical microbiology team was contacted for therapeutic advice in response to 32 (19%) reports. Of the remaining 137 reports, therapy was started or altered in response to 30 (22%) reports, but was considered appropriate in only seven (22%) of these.

Electromyography of some respiratory muscles in the horse

To investigate activity in respiratory muscles, insulated wire electrodes were used to record electromyographic activity in the costal diaphragm and in the intercostal, serratus ventralis, internal abdominal oblique, transversalis and rectus abdominis muscles in conscious horses and in the same animals when anaesthetised. Electromyographic activity was related to respiratory phases as recorded by a stethograph around the chest wall. The costal diaphragm showed tonic and inspiratory activity in both conscious and anaesthetised animals. The principal muscle actively involved in expiration was the transversalis muscle. Intercostal muscle activity, and any increased activity in the second part of either inspiration or expiration recorded in the conscious animal, was absent under anaesthesia. The very marked tonic activity found in the serratus ventralis muscle in standing horses disappeared during anaesthesia. It was concluded that any stabilisation of the chest wall contributed by activity in the serratus ventralis and intercostal muscles in conscious, standing horses is greatly reduced during anaesthesia.

Electromyographic study of the cat's diaphragm during oesophageal distension

In 10 cats, under acute experimental conditions, the effects of distension of the oesophagus on diaphragmatic activity were studied. Bipolar recording electrodes were implanted in the diaphragmatic dome muscular fibres and crura muscular fibres. Electrodes similar to those in the diaphragm were inserted in the oesophageal muscular wall above the hiatus and in the rectus abdominis muscle. Changes in the intrathoracic pressure and blood pressure were recorded by catheters placed in the pleural cavity and carotid artery respectively. Distension of the lower part of the thoracic oesophagus (at the level between the heart and the hiatus, 5 to 7 cm from the hiatus) by inflating a balloon with 10 to 15 ml of air produced a partial or total inhibition of the inspiratory electrical activity of the inner hiatal muscular fibres, while the inspiratory electrical activity of the dome muscular fibres was generally unchanged. This inhibition was increasingly pronounced as the distension volume increased and as the balloon was positioned nearer to the hiatus. During the distension period, only electrocardiographic potentials were recorded on the oesophageal muscular wall and rectus abdominis muscle traces and no significant changes were observed from intrathoracic pressure or blood pressure channels. Distension by means of a balloon either inflated with up to 5 ml of air when placed 5 to 7 cm cranial to the hiatus or inflated with 15 ml of air when localised in the cervical oesophagus and intrahiatally produced no effect. All areas of the diaphragm were silent during expiration.