Value sharing and food system dynamics for milk, tomato, and cereals food chains

The aim of the paper is to analyse value sharing and food system dynamics of milk, tomato, and cereals food chains, so to explore the agro-food enterprises capacity to be competitive and sustainable. The paper is based on the functionalist approach of Malassis and the notion of the system of the General Systems Theory. The methodology is aimed at creating a consolidated financial statement for each food chain so to re-create the chain value and identify how this is shared among the different food chain stages. The analysis is carried out on primary and secondary data: around 2400 financial statements concerning 480 enterprises from 2003 to 2007 and stakeholders\u2019 interviews. Results show that value is usually created in the processing and distribution stages, to the detriment of the primary sector, and that the retail managing practices tend to impose damaging structural changes on farms whose profitability is at times becoming sustainable only thanks to European subsidies. To conclude, there is evidence of inadequate definition of strategic and network alliance along the chain. Competitiveness is still a concept achieved by single food chain stages against others and food chain internal competition entails a declining sustainability of small farms and enterprises

Effects of the modification of gas diffusion electrodes by organic redox catalysts for hydrogen peroxide electrosynthesis

This paper reports a comparative study of the electrochemical performance of in situ hydrogen peroxide electrogeneration on gas diffusion electrodes modified by organic redox catalysts 2-ethylanthraquinone, 2-terc-butylanthraquinone and azobenzene in medium of 0.1 mol L-1 H2SO4 plus 0.1 mol L-1 K2SO4, pH = 1. Hydrogen peroxide generation proved strongly dependent on the applied potential and on the concentration of added catalysts. Electrode modifications led to a significant increase in H2O2 yield (30%) reaching 850 mg L-1, and the overpotential for oxygen reduction shifted to less negative values (400 mV vs Ag/AgCl for electrodes modified by quinones and 300 mV vs Ag/AgCl for electrodes modified by azobenzene) compared to noncatalyzed gas diffusion electrodes, resulting in reduced energy consumption of 596.5 to 232.4 kWh kg-1. The results indicated that the best electrode for H2O2 electrogeneration is the gas diffusion electrode modified with 10% of 2-ethylanthraquinone, offering the best cost to benefit ratio.Este trabalho apresenta um estudo comparativo da eficiência eletroquímica na eletrogeração de peróxido de hidrogênio in situ usando eletrodos da difusão gasosa modificados com os catalisadores orgânicos redox: 2-etilantraquinona, 2-terc-butilantraquinona e azobenzeno em meio de 0,1 mol L-1 H2SO4 + 0,1 mol L-1 K2SO4, pH = 1. A produção de peróxido de hidrogênio está diretamente relacionada ao potencial aplicado e a concentração dos catalisadores adicionados. A modificação dos eletrodos resultou em um aumento significativo no rendimento de H2O2 (30%) alcançando 850 mg L-1 e o sobrepotencial da reação de redução do oxigênio foi deslocado para valores menos negativos (400 mV vs Ag/AgCl para os eletrodos modificados com quinonas e 300 mV vs. Ag/AgCl para os eletrodos modificados com azobenzeno) comparado ao eletrodo de difusão gasosa não modificado, reduzindo o consumo de energia de 596,5 para 232,4 kWh kg-1. Os resultados indicaram que o melhor eletrodo para a eletrogeração do H2O2 é o eletrodo de difusão gasosa modificado com 10% de 2-etilantraquinona, o qual apresentou a melhor relação custo/benefício.643650Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Reator Eletroquìmico Para Eletrogeração De Peróxido De Hidrogênio

Este desenvolvimento refere-se a um equipamento (reator eletroquímico e/ou eletrolítico) destinado a produção de peróxido de hidrogênio a partir da redução do oxigênio dissolvido em solução. Este equipamento utiliza processos eletroquímicos e/ou eletrolíticos, através de células eletroquímicas e/ou eletrolíticas empregando catodos tridimensionais, metálicos ou carbonosos, tipo esponja. Duas configurações de reatores, denominadas de fluxo paralelo e fluxo transversal, foram avaliadas. A eficiência do reator eletroquímico e/ou eletrolítico desenvolvido foi verificada com relação à distância anodo/catodo, velocidade do fluido e a presença de promotores de turbulência, pelo monitoramento da concentração de peróxido de hidrogênio eletrogerada. Concentrações de H2O2 acima de 700 mg L-1 foram obtidas após cinco horas de experimento na configuração de fluxo transversal otimizada, com uma eficiência de corrente de 85% e consumo energético de 4,5 kWh kg-1.BR0203017 (A)C25B1/30C25B1/30BR20020203017C25B1/30C25B1/3

Considerations on the hydrogen peroxide electrogeneration

This paper presents some results that may be used as previous considerations to a hydrogen peroxide electrogeneration process design. A kinetic study of oxygen dissolution in aqueous solution is carried out and rate constants for oxygen dissolution are calculated. Voltammetric experiments on vitreous carbon cathode shown that the low saturation concentration drives the oxygen reduction process to a mass transfer controlled process which exhibits low values of limiting currents. Results have shown that the hydrogen peroxide formation and its decomposition to water are separated by 400 mV on the vitreous carbon surface. Diffusion coefficients for oxygen and hydrogen peroxide are calculated using data taken from Levich and Tafel plots. In a series of bulk electrolysis experiments hydrogen peroxide was electrogenerated at several potential values, and concentration profiles as a function of the electrical charged passed were obtained. Data shown that, since limiting current plateaus are poorly defined onto reticulated vitreous carbon, cathodic efficiency may be a good criterion for choosing the potential value in which hydrogen peroxide electrogeneration should be carried out.25225

Effects of the modification of gas diffusion electrodes by organic redox catalysts for hydrogen peroxide electrosynthesis

This paper reports a comparative study of the electrochemical performance of in situ hydrogen peroxide electrogeneration on gas diffusion electrodes modified by organic redox catalysts 2-ethylanthraquinone, 2-terc-butylanthraquinone and azobenzene in medium of 0.1 mol L-1 H2SO4 plus 0.1 mol L-1 K2SO4, pH = 1. Hydrogen peroxide generation proved strongly dependent on the applied potential and on the concentration of added catalysts. Electrode modifications led to a significant increase in H2O2 yield (30%) reaching 850 mg L-1, and the overpotential for oxygen reduction shifted to less negative values (400 mV vs Ag/AgCl for electrodes modified by quinones and 300 mV vs Ag/AgCl for electrodes modified by azobenzene) compared to noncatalyzed gas diffusion electrodes, resulting in reduced energy consumption of 596.5 to 232.4 kWh kg-1. The results indicated that the best electrode for H2O2 electrogeneration is the gas diffusion electrode modified with 10% of 2-ethylanthraquinone, offering the best cost to benefit ratio

Bibliometric study on SDG 6: analysing main content aspects by using Web of Science data from 2015 to 2021

Purpose: The purpose of the article is to understand how the literature has been addressing the United Nations' Sixth Sustainable Development Goal (SDG) to obtain an overview of the current scenario and future perspectives. Design/methodology/approach: For that, a bibliometric analysis will be conducted with documents published between 2015 and 2021 and present in the Web of Science database. Initially, 328 documents were identified, and after careful reading of titles and abstracts, 239 documents were analysed. The documents were analysed using tools available on the Web of Science database and the software Bibliometrix. Findings: Amongst the results generated, it should be highlighted the identification of the motor themes “sustainable development” + “developing countries” and “water security”, presenting a significant relevance to the field and a high development level. In addition, “human rights” was verified as an emerging theme in the context of SDG 6 debates. Originality/value: The information provided here offers good documentation of the extent to which SDG 6 is documented in the literature and can be helpful for researchers interested in the topic

Is Brain-Derived Neurotropic Factor Methylation Involved in the Association Between Prenatal Stress and Maternal Postnatal Anxiety During the COVID-19 Pandemic?

BackgroundThe COVID-19 pandemic is a collective trauma that may expose susceptible individuals to high levels of stress. Pregnant women represent a high-risk population, considering that pregnancy is a period of heightened neuroplasticity and susceptibility to stress through epigenetic mechanisms. Previous studies showed that the methylation status of the BDNF gene is linked with prenatal stress exposure. The goals of this study were (a) to assess the association between pandemic-related stress and postnatal anxiety and (b) to investigate the potential role of maternal BDNF methylation as a significant mediator of this association. MethodsIn the present study, we report data on the association among pandemic-related stress during pregnancy, maternal BDNF methylation, and postnatal anxiety symptoms. Pandemic-related stress and postnatal anxiety were assessed through self-report instruments. BDNF methylation was estimated in 11 CpG sites in DNA from mothers' buccal cells. Complete data were available from 108 mothers. ResultsResults showed that pandemic-related stress was associated with an increased risk of postnatal anxiety, r = 0.20, p < 0.05. CpG-specific BDNF methylation was significantly associated with both prenatal pandemic-related stress, r = 0.21, p < 0.05, and postnatal maternal anxious symptoms, r = 0.25, p = 0.01. Moreover, a complete mediation by the BDNF CpG6 methylation emerged between pandemic-related stress during pregnancy and postnatal maternal anxiety, ACME = 0.66, p < 0.05. ConclusionThese findings suggest that BDNF epigenetic regulation by pandemic-related stress might contribute to increase the risk of anxiety in mothers. Policymakers should prioritize the promotion of health and wellbeing in pregnant women and mothers during the present healthcare emergency

Electrochemical removal of CuII in the presence of humic acid

The removal of CuII (10 mg L-1) complexed by commercial humic acid (100 mg L-1) was studied at different current densities (30-80 mA cm-2) using a filter-press cell, Ti/Ru0.3Ti0.7O2 anode and stainless steel cathode. The electrolyses were performed with and without membrane separating the cell compartments [(homogeneous anionic (Nafion R117), heterogeneous cationic (Ionac MC-3470) and heterogeneous anionic (Ionac MA-3475)]. The influence of the membrane on the rate of CuII removal was bigger for cationic membranes. Current efficiencies up to ca. 55% (Ionac MC-3470) for CuII removal at 30 mA cm-2 were obtained. By combining oxidation and reduction, 100% CuII removal was achieved at current efficiencies of 75%. The main path for the removal is the electrostatic interaction with the anode followed by diffusion through the membrane and deposition at the cathode. Additionally, the oxidative degradation of humic acid contributes to the rate of CuII removal.A remoção de CuII (10 mg L-1) complexado por ácido húmico comercial (100 mg L-1) foi estudada a diferentes densidades de corrente (30-80 mA cm-2) usando uma célula filtro-prensa, ânodo de Ti/Ru0.3Ti0.7O2 e cátodo de aço inoxidável. As eletrólises foram feitas com e sem membrana separando os compartimentos da célula [aniônica homogênea (Nafion R117), catiônica heterogênea (Ionac MC-3470) e aniônica heterogênea (Ionac MA-3475)]. A influência da membrana na velocidade de remoção de CuII foi maior com as catiônicas. Foi obtida eficiência de corrente de ca. 55% (Ionac MC-3470) para remoção de CuII a 30 mA cm-2. Combinando oxidação e redução, foi obtida remoção de 100% de CuII com eficiência de corrente de 75%. A etapa principal para a remoção é interação eletrostática com o ânodo, seguida pela difusão através da membrana e deposição sobre o cátodo. Adicionalmente, a degradação oxidativa de ácido húmico contribui com a velocidade de remoção de CuII.651658Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Modifiable and non-modifiable factors related to HPV infection and cervical abnormalities in women at high risk: a cross-sectional analysis from the Valhidate Study

Abstract: Migrant women, and women infected with HIV, are at enhanced risk of cervical HPV infection and HPV-related cancers. We investigated factors that can reduce these risks through public health preventive and screening interventions. We compared prevalence and risk factors for cervical HPV infection/lesions in women with HIV-infection (HIW) and migrant women (RMW) with a control group of resident women (SPW) who were enrolled in the study for the eVALuation and monitoring of HPV Infections and relATEd cervical diseases in high-risk women (VALHIDATE). Among 3093 evaluable women, age-standardized HPV prevalence was 36.3% (95%CI: 28.1\u201344.4) in HIW, 21.6% (95%CI: 15.7\u201327.5) in RMW, and 14.3% (95%CI: 12.5\u201316.1) in SPW. Adjusted prevalence of HPV infection was 2.07 times higher among HIW (95%CI: 1.75\u20132.45), and 1.45 times higher among RMW (95%CI: 1.17\u20131.80) than in SPW. Prevalence-ratios of SIL and HG-SIL were 2.67 (95%CI: 2.06\u20133.45) and 2.82 (95%CI: 1.28\u20136.20), respectively, in HIW compared to controls. A multivariate log-binomial regression model showed modifiable risk factors associated with HPV infection/lesion to have different patterns among groups. Specific public-health intervention, including health and sexual-health education, safe-sex procedures, and improvements to screening programmes, could favorably affect these highly vulnerable women