Culture and Human Capital Investments: Evidence of an Unconditional Cash Transfer Program in Bolivia

This paper uses a policy quasi-experiment created by the introduction of an old-age unconditional cash transfer program in Bolivia to study the intra-household income allocation process towards children's educational expenditure by ethnicity and gender of the recipient. Taking advantage of a sharp discontinuity created by the program assignment mechanism, I investigate the heterogeneity in the patterns of allocation within indigenous, multiethnic, and non-indigenous families, conditional on having one elder and one school-age child living in the household. I find that cultural factors (proxied by ethnicity) count in the decision making process of human capital investments. In particular, the allocation of resources within indigenous families follows rules closely related to patriarchal family structures (in which women have limited decision-making power) and is consistent with unitary, dictatorial, and common preferences theoretical household models. Conversely, non-indigenous families follow decision rules more closely related to collective and bargaining behavior models.Bolivia, culture, Bolivida, educational expenditure

Localització, ens ubiquem?

El terme localització és un calc de l'anglès molt utilitzat en àmbits especialitzats i molt polèmic, que designa el procés d'adaptació lingüística i cultural d'un producte informàtic a un mercat determinat. Aquest article descriu els arguments a favor i en contra de l'ús d'aquest terme, els orígens i la situació actual

Performance of an industrial biofilter from a composting plant in the removal of ammonia and VOCs after material replacement

BACKGROUND: Biofiltration is a suitable odor reduction technique for the treatment of gaseous emissions from composting processes, but little is known about the start-up of full-scale biofilters after material replacement and their performance after several years of operation. - RESULTS: Biofilter material (wood chips used previously as bulking agent in a composting process) can effectively remove ammonia and most of the volatile organic compounds (VOCs) content, achieving removal efficiencies greater than 70% for VOCs and near 90% for ammonia immediately after material replacement. These removal efficiencies were maintained for several months after material replacement. In the studied full-scale biofilter no lag phase was observed in the removal of ammonia whereas in the case of VOCs different patterns were detected during biofilter start-up. For the old biofilter material, after 4 years of operation, a statistically significant decrease of removal efficiency for ammonia in comparison with the new material was detected. No statistically significant differences were found in the case of VOCs. - CONCLUSIONS: Data on the emissions of several pollutants from biofilters treating composting exhaust gases have been systematically obtained. The tested filtering media presented adequate properties for biofiltration of gases emitted during the composting process

Interplay between R513 methylation and S516 phosphorylation of the cardiac voltage-gated sodium channel

Arginine methylation is a novel post-translational modification within the voltage-gated ion channel superfamily, including the cardiac sodium channel, Naᵥ1.5. We show that Naᵥ1.5 R513 methylation decreases S516 phosphorylation rate by 4 orders of magnitude, the first evidence of protein kinase A inhibition by arginine methylation. Reciprocally, S516 phosphorylation blocks R513 methylation. Naᵥ1.5 p.G514C, associated to cardiac conduction disease, abrogates R513 methylation, while leaving S516 phosphorylation rate unchanged. This is the first report of methylation–phosphorylation cross-talk of a cardiac ion channel

Adsorption, absorption and biological degradation of ammonia in different biofilter organic media

A tailor-made apparatus called ammoniometer, which is a batch mode respirometer applied to the study of ammonia biodegradation in biofilter media, has been used to evaluate adsorption, absorption, and biodegradation in five different organic materials (compost, coconut fibre, bark, pruning wastes, and peat) obtained from full-scale biofilters in operation in several waste treatment plants. The results showed that absorption could be represented by a Henry's law linear equation, with values of the Henry coefficient significantly higher (from 1,866 to 15,320) than that of pure water (1,498). Adsorption data were successfully fitted to Langmuir and Freundlich isotherms and maximum adsorption capacity varies from 1.06 to 1.81 mg NH(3)/g dry media. Ammonia biodegradation rates for each organic material were also calculated. Biodegradation rates varied from 0.67 to 7.82 mg NH(3)/kg media/d depending on the material tested. The data obtained showed important differences in the behaviour of the biofilter organic media, which has important implications in the design and modelling of these systems

Composting of dewatered wastewater sludge with various ratios of pruning waste used as a bulking agent and monitored by respirometer

The effects of different volumetric ratios of wastewater sludge to bulking agent on the performance of full-scale composting were studied. Volumetric ratios of wastewater sludge to pruning waste, used as a bulking agent, were 1:2 (Pile 1), 1:2.5 (Pile 2) and 1:3 (Pile 3). Experiments were carried out in an uncovered plant using windrow composting with weekly turning. To monitor the evolution of the three composting piles, routine parameters such as temperature and interstitial oxygen level, chemical parameters such as organic matter, moisture and C/N ratio, and biologically related indices such as respiration indices at process temperature (RIprocess) and at 37 °C (RI₃₇) were monitored. Different responses were observed in the three piles; Pile 1 did not accomplish the necessary requirements in terms of sanitation and RIprocess for a typical composting process; Piles 2 and 3 presented a similar behaviour, reaching thermophilic temperatures for a long period and, due to their high biological activity, high RIprocess. The quality of the product obtained in the three piles in terms of stability (RI₃₇ and the Rottegrade self-heating test) and maturity (germination index) were measured, with compost from Pile 3 the most stable. To achieve satisfactory stability and sanitation for application to land, optimisation of the sludge to bulking agent ratio used to process wastewater sludge into compost appears to be crucial

Biofiltration for ammonia removal from composting exhaust gases

A study was conducted to investigate the utilization of mature compost as a biofilter media for the removal of ammonia from the exhaust gases of the composting process. Source-selected organic fraction of municipal solid wastes, digested wastewater sludge and animal by-products were composted in a pilot-scale reactor and the exhaust gas was treated in a biofilter. Due to the high ammonia adsorption and absorption capacity of the compost media, no delay or start-up phase was observed and high removal efficiencies were achieved from the beginning of the experiments. A global ammonia removal efficiency of 95.9% was obtained in the biofilter for a loading rate range of 846-67,100 mg NH₃ m⁻³ biofilter h⁻¹. However, an important reduction of ammonia removal was observed when the waste gas contained high NH₃ concentration (more than 2000 mg NH₃ m⁻³), which corresponded with the case of animal by-products composting

Emission of volatile organic compounds from composting of different solid wastes : abatement by biofiltration

Emission of volatile organic compounds (VOCs) produced during composting of different organic wastes (source-selected organic fraction of municipal solid wastes (OFMSW), raw sludge (RS) and anaerobically digested wastewater sludge (ADS) and animal by-products (AP)) and its subsequent biofiltration have been studied. Composting was performed in a laboratory scale composting plant (30 l) and the exhaust gases generated were treated by means of a compost biofilter. VOCs concentration in the composting exhaust gases for each composting process ranged from 50 to 695 mg C m⁻³ for OFMSW (5:1), from 13 to 190 mg C m⁻³ for OFMSW (1:1), from 200 to 965 mg C m⁻³ for RS, from 43 to 2900 mg C m⁻³ for ADS and from 50 to 465 mg C m⁻³ for AP. VOCs emissions were higher during the beginning of the composting process and were not generally related to the biological activity of the process. These emissions corresponded to an average loading rate applied to the biofilter from 2.56 to 29.7 g C m⁻³ biofilter h⁻¹. VOCs concentration in the exhaust gas from the biofilter ranged from 55 to 295 mg C m⁻³ for OFMSW (5:1), from 12 to 145 mg C m−3 for OFMSW (1:1), from 55 to 270 mg C m−3 for RS, from 42 to 855 mg C m⁻³ for ADS and from 55 to 315 mg C m⁻³ for AP. Removal efficiencies up to 97% were achieved although they were highly dependent of the composted waste. An important observation was that the compost biofilter emitted VOCs with an estimated concentration of 50 mg C m⁻³

Coupling composting and biofiltration for ammonia and volatile organic compounds removal

The efficiency of a compost biofilter for the simultaneous removal of ammonia and volatile organic compounds (VOCs) from exhaust gases of the composting process of different organic wastes (source-selected organic fraction of municipal solid wastes and animal by-products) is studied. An average ammonia removal efficiency of 94.7% was obtained in the biofilter for an average loading rate range of 846-to 67100 mg [NH3] m⁻³ biofilter h⁻¹. However, a sharp reduction in NH3 removal was observed when the waste gas contained a high, more than 2000 mg m⁻³, NH3 concentration. The maximum VOC removal efficiency was 82% when the biofilter worked at a loading rate range of 0.55-28.8 g [C] m⁻³ biofilter h⁻¹

Composting of dewatered wastewater sludge with various ratios of pruning waste used as a bulking agent and monitored by respirometer

The effects of different volumetric ratios of wastewater sludge to bulking agent on the performance of full-scale composting were studied. Volumetric ratios of wastewater sludge to pruning waste, used as a bulking agent, were 1:2 (Pile 1), 1:2.5 (Pile 2) and 1:3 (Pile 3). Experiments were carried out in an uncovered plant using windrow composting with weekly turning. To monitor the evolution of the three composting piles, routine parameters such as temperature and interstitial oxygen level, chemical parameters such as organic matter, moisture and C/N ratio, and biologically related indices such as respiration indices at process temperature (RIprocess) and at 37 °C (RI₃₇) were monitored. Different responses were observed in the three piles; Pile 1 did not accomplish the necessary requirements in terms of sanitation and RIprocess for a typical composting process; Piles 2 and 3 presented a similar behaviour, reaching thermophilic temperatures for a long period and, due to their high biological activity, high RIprocess. The quality of the product obtained in the three piles in terms of stability (RI₃₇ and the Rottegrade self-heating test) and maturity (germination index) were measured, with compost from Pile 3 the most stable. To achieve satisfactory stability and sanitation for application to land, optimisation of the sludge to bulking agent ratio used to process wastewater sludge into compost appears to be crucial