Environmental Costs of Government-Sponsored Agrarian Settlements in Brazilian Amazonia

Brazil has presided over the most comprehensive agrarian reform frontier colonization program on Earth, in which ~1.2 million settlers have been translocated by successive governments since the 1970's, mostly into forested hinterlands of Brazilian Amazonia. These settlements encompass 5.3% of this ~5 million km2 region, but have contributed with 13.5% of all land conversion into agropastoral land uses. The Brazilian Federal Agrarian Agency (INCRA) has repeatedly claimed that deforestation in these areas largely predates the sanctioned arrival of new settlers. Here, we quantify rates of natural vegetation conversion across 1911 agrarian settlements allocated to 568 Amazonian counties and compare fire incidence and deforestation rates before and after the official occupation of settlements by migrant farmers. The timing and spatial distribution of deforestation and fires in our analysis provides irrefutable chronological and spatially explicit evidence of agropastoral conversion both inside and immediately outside agrarian settlements over the last decade. Deforestation rates are strongly related to local human population density and road access to regional markets. Agrarian settlements consistently accelerated rates of deforestation and fires, compared to neighboring areas outside settlements, but within the same counties. Relocated smallholders allocated to forest areas undoubtedly operate as pivotal agents of deforestation, and most of the forest clearance occurs in the aftermath of government-induced migration

Effect of Biodiversity Changes in Disease Risk: Exploring Disease Emergence in a Plant-Virus System

The effect of biodiversity on the ability of parasites to infect their host and cause disease (i.e. disease risk) is a major question in pathology, which is central to understand the emergence of infectious diseases, and to develop strategies for their management. Two hypotheses, which can be considered as extremes of a continuum, relate biodiversity to disease risk: One states that biodiversity is positively correlated with disease risk (Amplification Effect), and the second predicts a negative correlation between biodiversity and disease risk (Dilution Effect). Which of them applies better to different host-parasite systems is still a source of debate, due to limited experimental or empirical data. This is especially the case for viral diseases of plants. To address this subject, we have monitored for three years the prevalence of several viruses, and virus-associated symptoms, in populations of wild pepper (chiltepin) under different levels of human management. For each population, we also measured the habitat species diversity, host plant genetic diversity and host plant density. Results indicate that disease and infection risk increased with the level of human management, which was associated with decreased species diversity and host genetic diversity, and with increased host plant density. Importantly, species diversity of the habitat was the primary predictor of disease risk for wild chiltepin populations. This changed in managed populations where host genetic diversity was the primary predictor. Host density was generally a poorer predictor of disease and infection risk. These results support the dilution effect hypothesis, and underline the relevance of different ecological factors in determining disease/infection risk in host plant populations under different levels of anthropic influence. These results are relevant for managing plant diseases and for establishing conservation policies for endangered plant species

Combining remote sensing and household level data for regional scale analysis of land cover change in the Brazilian Amazon

Land cover change in the Brazilian Amazon depends on the spatial variability of political, socioeconomic and biophysical factors, as well as on the land use history and its actors. A regional scale analysis was made in Rondônia State to identify possible differences in land cover change connected to spatial policies of land occupation, size and year of establishment of properties, accessibility measures and soil fertility. The analysis was made based on remote sensing data and household level data gathered with a questionnaire. Both types of analyses indicate that the highest level of total deforestation is found inside agrarian projects, especially in those established more than 20 years ago. Even though deforestation rates are similar inside and outside official settlements, inside agrarian projects forest depletion can exceed 50% at the property level within 10–14 years after establishment. The data indicate that both small-scale and medium to large-scale farmers contribute to deforestation processes in Rondônia State encouraged by spatial policies of land occupation, which provide better accessibility to forest fringes where soil fertility and forest resources are important determinants of location choic

Effect of curing time on the microstructure and mechanical strength development of alkali activated binders based on vitreous calcium aluminosilicate (VCAS)

The aim of this paper is to study the influence of curing time on the microstructure and mechanical strength development of alkali activated binders based on vitreous calcium aluminosilicate (VCAS). Mechanical strength of alkali activated mortars cured at 65 °C was assessed for different curing times (4¿168 h) using 10 molal NaOH solution as alkaline activator. Compressive strength values around 77 MPa after three days of curing at 65 °C were obtained. 1·68 MPa/h compressive strength gain rate was observed in the first 12 h, decreasing to 0·95 MPa/h for the period of 12¿72 h. The progress of geopolymeric reaction was monitored by means of TGA and, electrical conductivity and pH measurements in an aqueous suspension. Significant decrease in pH and electrical conductivity were observed in the 4¿72 h period, demonstrating the geopolymerization process. Furthermore, SEM images showed an important amount of (N, C)ASH gel and low porosity of the developed matrix.To the Ministerio de Ciencia e Innovacion (MICINN) of the Spanish Government (BIA2011-26947) and also to FEDER for funding and to Vitrominerals company for supplying VCAS samples.Mitsuuchi Tashima, M.; Soriano Martínez, L.; Borrachero Rosado, MV.; Monzó Balbuena, JM.; Paya Bernabeu, JJ. (2013). Effect of curing time on the microstructure and mechanical strength development of alkali activated binders based on vitreous calcium aluminosilicate (VCAS). Bulletin of Materials Science. 36:245-249. https://doi.org/10.1007/s12034-013-0466-zS24524936Bernal S A, Gutiérrez R M, Pedraza A L, Provis J L, Rodriguez E D and Delvasto S 2011 Cem. Concr. Res. 41 1Criado M, Fernández-Jiménez A, Sobrados I, Palomo A and Sanz J 2011 J. Eur. Ceram. Soc. avaiable onlineDavidovits J 2008 Geopolymer chemistry and applications Institute Geopolymere, Saint-Quentin, FranceDuxson P, Fernández-Jiménez A, Provis J L, Lukey G C, Palomo A and van Deventer J S J 2007 J. Mater. Sci. 47 2917Fernández-Jiménez A, Palomo A and Criado M 2005 Cem. Concr. Res. 35 1204Hossain A B, Shrazi S A, Persun J and Neithalath N 2008 J. Transp. Res. Board 2070 32Komnitsas K and Zaharaki D 2007 Miner. Eng. 20 1261Lampris C, Lupo R and Cheeseman C R 2009 Waste Manage. 29 368Lin T, Jia D, Wang M, He P and Liang D 2009 Bull. Mater. Sci. 32 77Lloyd R R, Provis J L and van Deventer J S J 2009 J. Mater. Sci. 44 608Marín-López C, Reyes Araiza J L, Manzano-Ramírez A, Rubio Avalos J C, Perez-Bueno J J, Muñiz-Villareal M S, Ventura-Ramos E and Vorobiev Y 2009 Inorg. Mater. 45 1429Najafi Kani E, Allahverdi A and Provis J L 2012 Cem. Concr. Comp. 34 25Neithalath N, Persun J and Hossain A 2009 Cem. Concr. Res. 39 473Pacheco-Torgal F, Castro-Gomes J and Jalali S 2008a Constr. Build. Mater. 22 1315Pacheco-Torgal F, Castro-Gomex J and Jalali S 2008b Constr. Build. Mater. 22 1201Pacheco-Torgal F, Castro-Gomex J and Jalali S 2008c Constr. Build. Mater. 22 2212Payá J, Borrachero M V, Monzó J, Soriano L and Tashima M M 2012 Mater. Lett. 74 223Puertas F, Martínez-Ramírez S, Alonso S and Vázquez T 2000 Cem. Concr. Res. 30 1625Puertas F, Barba A, Gazulla M F, Gómez M P, Palacios M and Martínez-Ramírez S 2006 Mater. Construc. 56 73Reig L, Tashima M M, Borrachero M V, Monzó J and Payá J 2010 II Simposio aprovechamiento de residuos agro-industriales como fuente sostenible de materiales de construcción p. 83Rodriguez E D, Bernal S A, Provis J, Payá J, Monzó J and Borrachero M V 2012 Cem. Concr. Comp. (submitted)Tashima M M, Borrachero M V, Monzó J, Soriano L and Payá J 2009 COMATCOMP09 p.421Tashima M M, Akasaki J L, Castaldelli V N, Soriano L, Monzó J, Payá J and Borrachero M V 2012 Mater. Lett. 80 50Xu H and van Deventer J S J 2000 Int. J. Miner. Process. 59 247Yao X, Zhang Z, Zhu H and Chen Y 2009 Thermochim. Acta 493 49Zivica V 2004 Bull. Mater. Sci. 27 179Zivica V, Balkovic S and Drabik M 2011 Constr. Build. Mater. 25 220

Inhibition of cyclooxygenase-2 decreases breast cancer cell motility, invasion and matrix metalloproteinase expression

BACKGROUND: Cyclooxygenase (COX) is the rate-limiting enzyme that catalyzes the formation of prostaglandins. The inducible isoform of COX (COX-2) is highly expressed in aggressive metastatic breast cancers and may play a critical role in cancer progression (i.e. growth and metastasis). However, the exact mechanism(s) for COX-2-enhanced metastasis has yet to be clearly defined. It is well established that one of the direct results of COX-2 action is increased prostaglandin production, especially prostaglandin E(2 )(PGE(2)). Here, we correlate the inhibition of COX-2 activity with decreased breast cancer cell proliferation, migration, invasion and matrix metalloproteinase (MMP) expression. METHODS: Breast cancer cells (Hs578T, MDA-MB-231 and MCF-7) were treated with selective COX-2 inhibitors (NS-398 and Niflumic acid, NA). Cell proliferation was measured by staining with erythrosin B and counting the viable cells using a hemacytometer. Cell migration and invasion were measured using migration and invasion chamber systems. MMP expression was determined by enzyme immunoassay (secreted protein) and real-time quantitative polymerase chain reaction (mRNA). RESULTS: Our results show that there is a decline in proliferation, migration and invasion by the Hs578T and MDA-MB-231 breast cancer cell lines in the presence of either low concentrations (1 μM or lower) NA or NS-398. We also report that MMP mRNA and protein expression by Hs578T cells is inhibited by NS-398; there was a 50% decrease by 100 μM NS-398. PGE(2 )completely reversed the inhibitory effect of NS-398 on MMP mRNA expression. CONCLUSION: Our data suggests that COX-2-dependent activity is a necessary component for cellular and molecular mechanisms of breast cancer cell motility and invasion. COX-2 activity also modulates the expression of MMPs, which may be a part of the molecular mechanism by which COX-2 promotes cell invasion and migration. The studies suggest that COX-2 assists in determining and defining the metastatic signaling pathways that promote the breast cancer progression to metastasis

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal