Comparison between disc and non-woven synthetic fabric filter media to prevent emitter clogging

The aim of this research was to compare the evolution of head loss in disc (130 mu m) and non-woven synthetic fabric filter media used to filter the water in drip irrigation systems. Two forms of treatment of the irrigation water were carried out: one with a chemical product (chlorine) and the other with none. The research used two different filter media: two for each treatment together with a fertigation technique with organic products in both types of treatment. The chemical treatment of the irrigation water was done by chlorination, in which the source of chlorine was sodium hypochlorite. Water from an open reservoir was used, in which a drip irrigation module was installed. The temporal variation in water quality over one year was analyzed, taking into consideration the physical, chemical, and biological parameters of water that can cause clogging problems in emitters. The results showed that, in irrigation water, the pH and iron chemical parameters presented an average risk of clogging, and the hydrogen sulfide parameters presented a high risk. The performance of the filters was analyzed by comparing the concentrations of the effluent on the disc and non-woven synthetic fabric filters in relation to the effluent's physical and biological parameters. An attempt was made to follow head loss evolution in relation to the volume filtered by the filters so as to make a comparative analysis. It could be seen that the evolution of head loss was more significant and quicker with the non-woven synthetic fabric filter than with the disc filter The level of clogging in the emitters was calculated by means of a uniform distribution index. The test area using the non-synthetic woven fiber filter presented the smallest level of clogging and the greatest water distribution index.51244145

Urban wild meat consumption and trade in Central Amazonia

The switch from hunting wild meat for home consumption to supplying more lucrative city marketsin Amazonia can adversely affect some game species. Despite this, information on the amounts of wild meateaten in Amazonian cities is still limited. We estimated wild meat consumption rates in 5 cities in the State ofAmazonas in Brazil through 1046 door-to-door household interviews conducted from 2004 to 2012. With thesedata, we modeled the relationship between wild meat use and a selection of socioeconomic indices. We thenscaled up our model to determine the amounts of wild meat likely to be consumed annually in the 62 urbancenters in central Amazonia. A total of 80.3% of all interviewees reported consuming wild meat during an averageof 29.3 (CI 11.6) days per year. Most wild meat was reported as bought in local markets (80.1%) or hunted by afamily member (14.9%). Twenty-one taxa were cited as consumed, mostly mammals (71.6%), followed by reptiles(23.2%) and then birds (5.2%). The declared frequency of wild meat consumption was positively correlated withthe proportion of rural population as well as with the per capita gross domestic product of the municipality(administrative divisions) where the cities were seated. We estimated that as much as 10,691 t of wild meat mightbe consumed annually in the 62 urban centers within central Amazonia, the equivalent of 6.49 kg per person peryear. In monetary terms, this amounts to US$21.72 per person per year or US$35.1 million overall, the latter figureis comparable to fish and timber production in the region. Given this magnitude of wild meat trade in centralAmazonia, it is fundamental to integrate this activity into the formal economy and actively develop policies thatallow the trade of more resilient taxa and restrict trade in species sensitive to hunting

Water treatment by sedimentation and slow fabric filtration using Moringa oleifera seeds

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The main objective of this work was to evaluate the suitability and efficiency of a natural coagulant from Moringa oleifera seeds in treating high turbidity water in the processes of slow direct filtration and sedimentation. In developing countries such as Brazil, the technologies for water treatment shall enable people living in potable-water deficient regions to purify water in easy and self-sustainable ways and at a low cost as well. Within this proposition, a potential use of M. oleifera has been suggested in several previous studies. In this work, a flocculation device made of pet bottles plus three filters consisting of pet bottles and non-woven synthetic fabric was used in the water treatment by slow direct filtration. The water output to the filters was of approximately 4 m(3)m-(2) per day. The water treatment by sedimentation comprised a flocculation unit made of pet bottles and a sedimentation tank. Synthetic bentonite-water was used as the untreated water, which was chosen due to its proper qualitative characteristics for the experiments. The data demonstrated that the M. oleifera coagulant was efficient in the treatment of water with high turbidity (50 to 100 NTU) in the tested systems of slow filtration through synthetic non-woven fabric and of sedimentation.51112561263Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)SAE/UnicampFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq [303889/2005-5]FAPESP [03/07709-3

PRE-FILTRATION IN BOULDER AND SLOW SAND FILTRATION WITH NON-WOVEN SYNTHETIC LAYERS AND GRANULATED VEGETAL COAL TO IMPROVE QUALITY IN WASTEWATER TREATED BY CONSTRUCTED WETLANDS

The objective of this study was the comparison between two filtration systems, being one composed of a boulder pre-filter followed by a slow filter with sand as filtration media and a non-woven synthetic fabric in the upper part, and the other one composed of a boulder pre-filter followed by a slow filter with sand as filtration media and granular activated charcoal and a non-woven synthetic fabric in the upper part, for the purification of household effluents treated in cultivated beds, to be applied in fertigation. The filtration systems were compared to assess the efficiency in the removal of the parameters: suspended solids, turbidity, apparent color, chemical oxygen demand, dissolved oxygen, iron, manganese, total coliforms and E. coli. The two systems operated 24 hours a day, with the same application rate, treating a total final flow of 1.5 m(3) day(-1), while the application rate for the pre-filtration unit was 8.4 m(3) m(-2) day(-1) on average and for each of the slow filtration units it was 2.7 m(3) m(-2) day(-1) on average. The pre-filtration and slow filtration units were efficient in the reduction of suspended solids concentrations, turbidity, apparent color and COD, for the purification of previously treated domestic sewage. The use of granular activated charcoal combined with sand in the slow filter allowed a higher efficiency in the removal of suspended solids, color, turbidity, total coliforms and E. Coli., without increasing the initial head loss. The use of effluents is possible in the fertigation practice, where the disinfection process may be necessary or not, depending on the cultivation and the irrigation system adopted.31480381

Water quality and bead loss in irrigation filters

Among the irrigation systems used today, trickle irrigation is one of the most efficient methods. This research, conducted by means of field tests, had the objective of comparing head loss evolution on water filtration with a disc filter (130 mum) and a non-woven synthetic fabric filter used in a drip irrigation system. The test consisted of fertirrigation with organic fertilizer, and chemical treatment of the water with sodium hypochlorite. Physical, chemical, and biological parameters were analyzed, such as: pH, turbidity, suspended solids, dissolved solids, EC, hardness, Langelier index, total iron, manganese, sulfides, algae, and bacteria. The water source used in this experiment was from an open reservoir, where an experimental trickle irrigation system had been installed. The research was developed in four steps lasting 30 days each, during different seasons. The chemical factors pH, total iron, and concentration of sulfides presented a medium risk of clogging the emitters. All other physical and biological water quality parameters analyzed resulted in values that did not present an emitter-clogging risk. There was a correlation of results between physical parameters turbidity, suspended solids, and algae, and suspended solids. Fertirrigation influenced water quality. The concentration of free chlorine was higher in the effluent from the disc filter. Head loss evolution in the non-woven synthetic fabric filter was more striking and faster than in the disc filter.61656357

The adjuvant mechanism of cationic dimethyldioctadecylammonium liposomes

Cationic liposomes are being used increasingly as efficient adjuvants for subunit vaccines but their precise mechanism of action is still unknown. Here, we investigated the adjuvant mechanism of cationic liposomes based on the synthetic amphiphile dimethyldioctadecylammonium (DDA). The liposomes did not have an effect on the maturation of murine bone-marrow-derived dendritic cells (BM-DCs) related to the surface expression of major histocompatibility complex (MHC) class II, CD40, CD80 and CD86. We found that ovalbumin (OVA) readily associated with the liposomes (> 90%) when mixed in equal concentrations. This efficient adsorption onto the liposomes led to an enhanced uptake of OVA by BM-DCs as assessed by flow cytometry and confocal fluorescence laser-scanning microscopy. This was an active process, which was arrested at 4° and by an inhibitor of actin-dependent endocytosis, cytochalasin D. In vivo studies confirmed the observed effect because adsorption of OVA onto DDA liposomes enhanced the uptake of the antigen by peritoneal exudate cells after intraperitoneal injection. The liposomes targeted antigen preferentially to antigen-presenting cells because we only observed a minimal uptake by T cells in mixed splenocyte cultures. The adsorption of antigen onto the liposomes increased the efficiency of antigen presentation more than 100 times in a responder assay with MHC class II-restricted OVA-specific T-cell receptor transgenic DO11.10 T cells. Our data therefore suggest that the primary adjuvant mechanism of cationic DDA liposomes is to target the cell membrane of antigen-presenting cells, which subsequently leads to enhanced uptake and presentation of antigen

Ultrasound-assisted synthesis of organotin compounds and their application as luminescent dye in silk fibroin scaffolds

In this work, we report the green synthesis of four luminescent organotin compounds 1–4 derived from amino acid Schiff bases (1: Naph-Trp-SnPh2, 2: Naph-Tyr-SnBu2, 3: Naph-Tyr-SnPh2, 4: Naph-Phe-SnPh2), obtained by ultrasound-assisted synthesis in short time (~20 min) and good yields (>95%). The molecular structure proposed in solution (1H and 119Sn NMR) was confirmed by X-ray diffraction study for compound 1 where the tin atom resides in trigonal bipyramid geometry. Luminescent silk fibroin scaffolds (SF 1–4) were elaborated with organotin compounds by freeze-drying technique. Photophysical properties of organotin compounds and scaffolds were obtained in solid state, observing bathochromic behaviors in tyrosine derived compounds, suggesting that the tyrosine produce supramolecular interactions across the –OH group that change the fluorescent properties. Scaffolds 1–4 were characterized by FTIR, XDR, TG/DTG, and SEM analysis. In addition, cytotoxic analysis of SF 1 presents high cellular viability, which could be applied as a scaffold in tissue engineering