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Universalising actions aimed at water supply in rural communities and indigenous populations must focus on simple and low-cost technologies adapted to the local context. In this setting, this research studied the dynamic gravel filter (DGF) as a pre-treatment to household slow-sand filters (HSSFs), which is the first description of a household multistage filtration scale to treat drinking water. DGFs (with and without a non-woven blanket on top of the gravel layer) followed by HSSFs were tested. DGFs operated with a filtration rate of 3.21 m3 m−2.d−1 and HSSFs with 1.52 m3 m−2.d−1. Influent water contained kaolinite, humic acid and suspension of coliforms and protozoa. Physical-chemical parameters were evaluated, as well as Escherichia coli, Giardia spp. cysts and Cryptosporidium spp. oocyst reductions. Removal was low (up to 6.6%) concerning true colour, total organic carbon and absorbance (λ = 254 nm). Nevertheless, HMSFs showed turbidity decrease above 60%, E. coli reduction up to 1.78 log, Giardia cysts and Cryptosporidium oocysts reductions up to 3.15 log and 2.24 log, respectively. The non-woven blanket was shown as an important physical barrier to remove solids, E. coli and protozoa.

The [Ru(NH3)5(H2O)]2+ andtrans-[Ru(NH3)4SO2(H2O)]2+ complexes ions were immobilized on poly(4-vinylpyridine) (4-PVP) through reactions in aqueous solutions. The stability of the imobilized complexes was checked in aqueous solution in the pH 2.0–8.0 range. The number of pyridinic nitrogens in the polymer 4-PVP is 2.80±0.05 mmol/g according to nitrogen elemental analysis. Potentiometric titration experiments showed that the accessible nitrogen, in aqueous medium, was 0.94±0.02 mmol/g with a pKa value of 7.4±0.2. In addition, ruthenium and sulfate analysis has demonstrated that about 15% of the accessible nitrogen sites are able to coordinate to the metal centers. The characterization of the immobilized complexes was made through diffuse electronic and infrared spectroscopies and differential pulse and cyclic voltammetries.

Emergent percutaneous transluminal coronary angioplasty (PTCA) is an effective treatment for acute myocardial infarction. However, occasionally results of angioplasty are suboptimal due to coronary dissection or elastic recoil, leading to a high chance of recurrent ischemia. Coronary stents are occasionally employed in such settings, but a high incidence of stent thrombosis was noted by early investigators when stents were placed into areas of active thrombus formation. Since coronary thrombosis and stent thrombosis are both initiated by platelets, the potent antiplatelet agent abciximab might be useful in preventing stent thrombosis. Little information is available concerning early outcome or 6-month clinical event rate when coronary artery stents are placed for suboptimal angioplasty results for acute myocardial infarction in patients given abciximab. We deployed 75 stents as part of angioplasty for acute myocardial infarction in 40 patients given abciximab. All patients had suboptimal angioplasty results leading to stent deployment. Each obtained normal flow angiographically and no stent thrombosis or acute closure was observed. Early mortality occurred in 1 patient. All patients were followed at least 6 months, and no patient died after hospital discharge. Three patients experienced recurrent ischemic events within the first 6 months. Two of these events were due to infarct vessel restenosis. We conclude the combined use of coronary artery stents and abciximab for suboptimal PTCA results during acute myocardial infarction is associated with a low incidence of culprit vessel recurrent ischemic events within 6 months of intervention.

Current prepping of the JohnsonJohnson stent deployment balloon can be suboptimal. This simple technique allows for an improved preparation of the stent delivery balloon prior to deployment, resulting in less air in the balloon during inflation.