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We provide explicit formulas for the effective fluid approach of $f(R)$ theories, such as the Hu & Sawicki and the designer models. Using the latter and simple modifications to the CLASS code, which we call EFCLASS, in conjunction with very accurate analytic approximations for the background evolution, we obtain competitive results in a much simpler and less error-prone approach. We also derive the initial conditions in matter domination and we find they differ from those already found in the literature for a constant $w$ model. A clear example is the designer model that behaves as $\Lambda$CDM in the background, but has nonetheless dark energy perturbations. We then use the aforementioned models to derive constraints from the latest cosmological data, including supernovae, BAO, CMB, $H(z)$ and growth-rate data, and find they are statistically consistent to the $\Lambda$CDM model. Finally, we show that the viscosity parameter $c_{vis}^2$ in realistic models is not constant as commonly assumed, but rather evolves significantly over several orders of magnitude, something which could affect forecasts of upcoming surveys., Comment: 24 pages, 12 figures, 5 tables. Changes match published version. The codes used in the analysis can be found at https://members.ift.uam-csic.es/savvas.nesseris/efclass.html and https://github.com/wilmarcardonac/EFCLASS

Eugenol (4-allyl-2-methoxyphenol) (1) has been reported to possess antioxidant and anticancer properties. In an attempt to enhance intrinsic activity of this natural compound, some derivatives were synthesized. Eugenol was extracted from cloves oil and further, the eugenol analogues (2-6) were obtained through acetylation and nitration reactions. Eugenol (1) and its analogues (2-6) were examined by in vitro model of cancer using two human cancer cell lines: DU-145 (androgen-insensitive prostate cancer cells) and KB (oral squamous carcinoma cells). Cell viability, by tetrazolium salts assay, was measured. Lactic dehydrogenase (LDH) release was also investigated to evaluate the presence of cell toxicity as a result of cell disruption, subsequent to membrane rupture. In the examined cancer cells, all compounds showed cell-growth inhibition activity. The obtained results demonstrate that the compounds 5-allyl-3-nitrobenzene-1,2-diol (3) and 4-allyl-2-methoxy-5-nitrophenyl acetate (5) were significantly (p < 0,001) more active than eugenol, with IC50 values in DU-145 cells of 19.02 x 10-6 and 21.5 × 10-6 mol L-1, respectively, and in KB cells of 18.11 × 10-6 and 21.26 × 10-6 mol L-1, respectively, suggesting that the presence of nitro and hydroxyl groups could be important in the activity of these compounds. In addition, our results seem to indicate that apoptotic cell demise appears to be induced in KB and DU-145 cells. In fact, in our experimental conditions, no statistically significant increase in LDH release was observed in cancer cells treated with eugenol and its analogues. Propriedades antioxidante e anticancerígena foram relatadas para o Eugenol (4-alil-2-metoxifenol) (1). Na tentativa de aumentar a atividade intrínseca deste composto natural, alguns derivados foram sintetizados. O eugenol foi extraído do óleo de cravo da Índia e seus análogos (2-6) foram obtidos por reações de acetilação e nitração. Eugenol (1) e seus análogos (2-6) foram avaliados in vitro frente a duas linhagens de células de câncer humanas: DU-145 (células de câncer de próstata, insensíveis a andrógeno) e KB (células de carcinoma escamoso oral). A viabilidade celular foi avaliada por ensaios com sal de tetrazólio. A liberação de desidrogenase lática (LDH) também foi investigada para avaliar a toxicidade celular como um resultado do rompimento celular subseqüente à ruptura da membrana. Todos os compostos apresentaram atividade inibitória sobre o crescimento das células cancerosas examinadas. Os resultados obtidos demonstram que os compostos 5-alil-3-nitrobenzeno-1,2-diol (3) e acetato de 4-alil-2-metoxi-5-nitrofenol (5) foram significativamente mais ativos que o eugenol (p < 0,001), com valores de IC50 em células DU-145 de 19,02 × 10-6 e 21,5 × 10-6 mol L-1 respectivamente, sugerindo que a presença dos grupos nitro e hidroxila podem ser importantes na atividade destes compostos. Os resultados também parecem indicar que a morte por apoptose está sendo induzida em células KB e DU-145. Nas condições experimentais avaliadas, não foi observado qualquer aumento estatisticamente significativo na liberação de LDH pelas células de câncer quando tratadas com eugenol e seus análogos.

Purpose: To determine and compare the antioxidant, antiproliferative and apoptotic effects of leaf infusions of Ilex laurina and Ilex paraguariensis in colon cancer cells.Methods: Antioxidant activity was determined by ORAC (Oxygen Radical Absorbance Capacity) and FRAP (Ferric Reducing Antioxidant Power). Cytotoxic and antiproliferative effects were analyzed using MTT ((3-(4, 5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) and sulfhorodamine-B respectively. Cell death and apoptosis of human colon adenocarcinoma cells SW480 and their metastatic-derived SW620 cells, were analyzed by flow cytometry using propidium iodide and Annexin-V.Results: Although their flavonoid levels were similar, I. laurina infusion contained 2.2 and 4.4 times higher amounts of total phenolic and caffeoyl derivatives, respectively, than I. paraguariensis. FRAP and ORAC values for I. laurina infusion were 1.6 and 2.0 more active than I. paraguariensis. Both plant infusions inhibited viability and cell growth of SW480 and SW620 cells. These results may be associated to cell cycle-arrest and apoptosis because of the comparable increase of hypodiploid and annexin-V positive colon cancer cells.Conclusion: These data highlight the antioxidant and promising anticancer activities of I. laurina and Ilex paraguariensis.Keywords: Ilex laurina, Ilex paraguariensis, Antioxidant, Antiproliferative, Apoptosis, Colon cancer

In the last decades, community forest management (CFM) has become an alternative to reach important objectives related to forests sustainability and the improvement of forest dwellers’ wellbeing. In many countries the recognition and development of specific CFM models has been closely related to social struggles for new rights or the recognition of traditional rights over land, which link it with the communitarian model. In order to understand the sequence of changes of CFM in the course of its recognition in Bolivia and particularly in the northern Bolivian Amazon, we considered three important social processes. The first social process relates to community devised distribution of land and forest resources in response to agricultural and forestry government reforms. The second social process relates to the debt-peonage system called “habilito” in the region, which barraca holders used to control their workforce, assure an adequate labor supply to exploit rubber and Brazil nuts, and to exercise influence over social relations and the local economy. The third process relates to the consequences of the dynamics triggered by the changes experienced by the first two, observed most of the time as different kind of conflicts, resulted from the difficulties of community members to adapt to the new social, political, normative and economic contexts. Related to the first social process, our findings suggest that within processes of changes of land property right and rights of forest use in favor or peasants and indigenous people, these actors needs to develop strategies to cope with the new legislation and new responsibilities, in which the principles of property and rights granted by the government might constitute themselves some kind of obstacle to people devising local principles of access and authority. Thus, the first step to community rule design, enforcement, and effective forest management is the opportunity to, and equity of, access to forest resources among members. The above changes carried out the rupture of the former dominant social relationships which is well observed within the negotiation of habilito. The study on habilito (second social process) suggests that after the above mentioned reforms, the habilito became a new instrument among the actors closely linked to forest resource use. To peasant and indigenous people habilito is a source of credit and goods, and to traders is an instrument to assure access to valuable forest resources. Within the process described above, when uncertainties and contradictions arise during the definition and application of new rules, conflicts emerge affecting individual and collective spheres. We called “conflict precursor” when individualistic behavior gives priority to individual goals, rather than collective goals. A conflict precursor becomes a “problem factor” when individual behavior represents an obstacle to reach collective agreements. This is the consequence of the different management and legal rules between livelihoods and valuable natural resources, and the confusion it represents for community members. Natural resource-based conflicts then, become a matter of who has the ability to use the resource in the most advantageous way