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Carbon block filters, commonly employed as point-of-use (POU) water treatment components, effectively eliminate pathogens and adsorb undesirable tastes, odors, and organic contaminants, all while producing no water waste. However, they lack the capability to remove arsenic. Enabling the carbon block to remove arsenic could reduce its exposure risks in tap water. Inspired by Sous vide cooking techniques, we developed a low-energy, low-chemical method for impregnating commercially available carbon block with titanium (hydr)oxide (THO) in four integrated steps: (1) vacuum removal of air from the carbon block, (2) impregnation with precursors in a flexible pouch, (3) sealing to prevent oxygen intrusion, and (4) heating in a water bath at 80 °C for 20 h to eliminate exposure and reactions with air. This process achieved a uniform 13 wt % Ti loading in the carbon block. Our modified carbon block POU filter efficiently removed both arsenate and arsenite from tap water matrices containing 10 or 100 μg/L arsenic concentrations in batch experiments or continuous flow operations. Surprisingly, the THO-modified carbon block removed arsenite better than arsenate. This innovative method, using 70% fewer chemicals than traditional autoclave techniques, offers a cost-effective solution to reduce exposure to arsenic and lower its overall risk in tap water.

Hematopoietic cells transplants are technically complex and expensive imposing a huge burden on health care systems, especially those in developing countries and regions. In 2017 > 4500 transplants were done in 13 Latin American countries with established transplant programmes. We interrogated data on transplant rate, cost, funding source, hospital type, Gini coefficient and the United Nations Development Programme Inequality-Adjusted Human Development Index to determine co-variates associated with transplant development. Transplant rates varied almost 30-fold between the 13 countries from 345 in Uruguay to 12 in Venezuela with a regional transplant rate 7–8-fold lower compared with the US and EU. We found significant correlations between higher transplant cost, public funding, transplants in private hospitals with transplant rate. Low cost pertransplant regardless of payor and transplants done in public hospitals were associated with low transplant rates. In contrast, high cost pertransplant funded by the government and transplants done in private hospitals were associated with high transplant rates. Surprisingly, we found transplant rates were higher when transplants cost more, when they were done in private for-profithospitals and payed for with public funds. These data give insights how to increase transplant rates in Latin America and other developing regions.

Biofilms cause a variety of pervasive problems in water treatment, distribution and reuse systems that are difficult to mitigate due to their resistance to disinfectants. We used magnetic phage-nanocomposite conjugates (PNCs) to target bacteria in biofilm inner layers for bottom-up eradication. Polyvalent Podoviridaephages PEB1 (54 nm) or PEB2 (86 nm) were covalently conjugated (viaamide bonds) with magnetic colloidal nanoparticle clusters (CNCs) of different sizes (150, 250 or 500 nm). Smaller CNCs with higher density of amino groups loaded phages more efficiently than the largest CNCs (e.g., for PEB1, 60 ± 4, 62 ± 5, and 47 ± 4 phages were loaded per μm2). Smaller PNCs dispersed phages more evenly throughout the biofilm bottom, significantly disrupting the biofilm bottom layer and detaching the biofilm within 6 h. The biofilm removal efficiency was 98.3 ± 1.4% for dual species biofilm (i.e., Escherichia coliand Pseudomonas aeruginosa) and 92.2 ± 3.1% for multi-species biofilm (i.e., E. coli, P. aeruginosa, and non-hosts Bacillus subtilisand Shewanella oneidensis). Large PNCs caused higher physical disruption but lower corresponding removal efficiencies (i.e., 80.2 ± 3.4% for dual species biofilm and 67.6 ± 3.8% for multi-species biofilm) due to lower horizontal diffusion at the bottom of the biofilm. A semi-empirical numerical model corroborated the higher biofilm removal efficiency with smaller PNCs and inferred that PNC size influences the mode of phage propagation: Small PNCs facilitate biofilm bottom clearance with significant horizontal dispersion while large PNCs mainly enhance vertical propagation. Overall, this study demonstrates the importance of size control to enhance the biofilm eradication capability of PNCs as an alternative or complementary biofilm control strategy.

No relevant conflicts of interest to declare.

More than a million HCT have been performed worldwide to date, but transplant rates and indications vary widely across regions. The Latin American Bone Marrow Transplantation Group (LABMT) was created under the auspices of the Worldwide Network for Blood and Marrow Transplantation (WBMT) in 2011 to assist in diffusing the practice, to integrate centers from multiple countries and to improve access to transplantation in the region. To evaluate the actual HCT activity, trends and contemporary practices in Latin America (LA), the LABMT surveyed centers for the annual activity from 2009 to 2012. Methods: The WBMT Global Activity Survey was used as a template and sent to all Hematology and HCT Societies in the region. This survey includes information of annual HCT numbers by center, indications, stem cell source and donor type. Results: A total of 11,116 HCT were performed between 2009 and 2012 with an increase in annual numbers from 2,517 in 2009 to 3,072 in 2012 (22%). The majority of the HCT were autologous (62%) with a 32% increase in activity over the period analyzed. In contrast, the increase in allogeneic HCT (6%) was relatively small. The majority of allogeneic HCT used related donors (n=3210), mostly HLA-identical peripheral blood (n=1812), bone marrow (n=1128) and non-identical related peripheral blood (n=156). Unrelated donor HCT (n=982) were performed mostly using cord blood (n=427), followed by bone marrow (n=332) and peripheral blood (n=223). In 2012, 91 teams from 12 countries reported 3,072 patients. Transplant rates (TR; HCT/10 million population) were 21 for allogeneic (ranging from 6 in Venezuela to 85 in Uruguay) and 60 for autologous HCT (ranging from 8 in Mexico to 215 in Uruguay). Unrelated donor TR was 5, ranging from 0 (Costa Rica, Panama, Peru, Paraguay and Venezuela) to 18 (Chile). Transplant center team density (team/10 million inhabitants) was 1.8 in 2012, with the highest in Uruguay (15), followed by Panama (8), Costa Rica (4), and Argentina (4). In comparison to other regions, transplant center density in LA was identical to the Asian Pacific region and lower than in Europe (7) or US/Canada (6). TR in LA compared to Asia/Pacific were higher for autologous (39 vs. 14) and lower for allogeneic (21 vs. 24, respectively, Table 1). Most transplant indications for autologous HCT (65% of all HCT) were plasma cell disorders (48%) and lymphomas (41%). Most allogeneic transplants (35% of all HCT) were performed for acute leukemias (58%, equally myeloid and lymphoid leukemias) and 18% for non-malignant disorders. Conclusion: While transplant indications are comparable to HCT performed in Europe and North America, transplant rates, transplant center and transplant team densities in LA are markedly lower. More autologous than allogeneic HCT are performed and autologous HCT increased considerably between 2009 and 2012. Unrelated donor TR is lower than in other regions. Initiatives are currently being taken to increase transplant activity, especially using alternative donor transplants within the region.