Efficiency and stability evaluation of Cu2O/MWCNTs filters for virus removal from water.

Both multi-walled carbon nanotubes (MWCNTs) and metal or metal oxides have demonstrated virus removal efficacy in drinking water applications. In this study, MWCNTs were coated with copper(I) oxide (Cu2O) using three distinct synthesis procedures (copper ion attachment, copper hydroxide precipitation, and [Cu(NH3)4]2+ complex attachment) and virus removal efficacy (using MS2 bacteriophages) was evaluated. All synthesis procedures resulted in the presence of adsorbed, nanosized Cu2O particles on the MWCNTs, shown using X-ray diffraction. Further, transmission electron microscopy confirmed uniform copper(I) oxide distribution along the MWCNTs for all three materials. Virus removal efficacy was assessed for all three synthesised composites both before and after material conditioning (filtering for at least 24 h/280 mL/h), and accounting for additional MS2 inactivation in the permeate due to continued copper inactivation from dissolved/desorbed copper in permeate (time-control). Material conditioning influenced virus removal, with the first litres of water containing higher concentrations of copper than the sixth litres of water, suggesting excess or non-bonded copper species dissolve from filters. Higher copper dissolution was observed for water at pH 5 than at pH 7, which decreased with time. Copper dissolution most likely caused an associated decrease in copper adsorbed to MWCNTs in the filters, which may explain the observed lower MS2 removal efficacy after conditioning. Additionally, the time-control study (immediately after filtration as compared to 2 h after filtration) highlighted continued MS2 inactivation in the permeate over time. The obtained results indicate that the synthesis procedure influences virus removal efficacy for MWCNTs coated with copper oxides and that virus removal is likely due to not only virus electrostatic adsorption to the coated MWCNTs, but also through antiviral properties of copper which continues to act in the permeate. In conclusion, it is highly important to revise the methods of testing filter materials for virus removal, as well as procedure for virus concentration evaluation.

[Posteromedial release combined with peritalar release in the treatment of congenital clubfoot]. / Uwolnienie tylno-przysrodkowe z nastawieniem okoloskokowym w leczeniu operacyjnym wrodzonej stopy konsko-szpotawej.

Basing on the authors' own experiences an attempt to assess the value of posteromedial release in treatment of congenital clubfoot was made. The procedure was performed in 70 feet in 52 children, age ranging from 6 months to 12 years, 90% of the procedures were performed before 4 years of age. Feet were classified as follows: a. non-coerrective--type III according to Marciniak, b. Partially corrective, c. in older children (> 4 years of age) in whom posteromedial release was combined with a lateral resection of the cuboid bone. Late results after 5-20 years (13 years on average) were assessed according to Magone's classification. Deformity free, fully functional feet were achieved in 60% cases. The authors stress the fact that posteromedial release is the method of choice in uncorrective cases of clubfeet, and in cases were conservative treatment was implemented after 10 months of age. In the procedure should be performed at the age of 2-3 months.

[The role of posterior release in the treatment program for congenital clubfoot]. / Miejsce uwolnienia tylnego w programie leczenia wrodzonej stopy konsko-szpotawej.

The aim of this paper was to assess the utility of this procedure and to define it's role in treatment of congenital clubfeet. The material comprises 123 children, among whom 154 feet were treated by posterior release. The age of the patients ranged from 5 to 36 months (average age: 16 months). The procedure involved the lengthening of the Achilles tendon in the sagittal plane, partial resection or transverse dissection of the articular capsule of the ankle joint. In selected cases lengthening of the tendon of the extensor hallucis muscle was performed and sometimes of the posticus muscle. The described procedure was performed in all cases where all forefoot components of the deformity were found, as well as an equines position of the foot. A group of 87 patients (70.7%), among whom posterior release was performed in 101 feet (65.6%). The follow-up time ranged from 5 to 15 years (average: 12.3 years). Results were assessed according to the classification by Magone et al. Very good results (95-100 points) were achieved in 27 feet (26.8%), good results (80-89 points) were found in 40 feet (39.6%), satisfactory (70-79 points) in 25 feet (24.7%), and bad results (less than 70 points) in 9 feet (8.9%). Basing on their own experience the authors' believe this procedure is very useful in treatment of congenital clubfeet. It's therapeutic usefulness is at it's best when deformities of the forefoot have been conservatively corrected. The extent of posterior release depends on the severity of the deformity.