Hacia un mejor entendimiento sobre los agricultores custodios y sus roles: percepciones de un estudio de caso en Cachilaya, Bolivia

Esta publicacion es el resultado de una investigacion colaborativa entre Bioversity International y la Fundacion para la Promocion e Investigacion de Productos Andinos (PROINPA). Se ocupa de las cuestiones relativas a la conservacion de la agrobiodiversidad en finca, un campo poco abordado por la investigacion, a pesar de su rol fundamental en el mantenimiento de la diversidad agrícola mundial. Actores estrategicos en la conservacion en las fincas son los agricultores que, por diversas razones, se distinguen de los demas por su contribucion a la conservacion de la diversidad de cultivos. Los llamamos ‘agricultores custodios’, a pesar de que la terminología pueda no ser adecuada para todos los contextos sociales. El entender quienes son los agricultores custodios, su presencia en el territorio, los tipos de cultivos que mantienen, el por que y como lo hacen, así como el adquirir conocimientos sobre los factores culturales, sociales y economicos detras de sus esfuerzos es, para los científicos, un paso muy importante en la elaboracion de estrategias efectivas de conservación en finca. Las entrevistas abiertas y la observacion participante son metodologías utiles para guiar futuros enfoques metodologicos y así avanzar en la comprension de como los roles de los agricultores custodios pueden ser mejor reconocidos, aprovechados y apoyados por la sociedad. Este trabajo ha sido realizado en el marco de un importante proyecto mundial de las Naciones Unidas apoyado por el FIDA y la Comision Europea, que se centra en el desarrollo de enfoques participativos e innovadores para la conservacion en finca de Especies Olvidadas y Subutilizadas (EOS)

3D ground model development for an active landslide in Lias mudrocks using geophysical, remote sensing and geotechnical methods

A ground model of an active and complex landslide system in instability prone Lias mudrocks of North Yorkshire, UK is developed through an integrated approach, utilising geophysical, geotechnical and remote sensing investigative methods. Surface geomorphology is mapped and interpreted using immersive 3D visualisation software to interpret airborne light detection and ranging data and aerial photographs. Subsurface structure is determined by core logging and 3D electrical resistivity tomography (ERT), which is deployed at two scales of resolution to provide a means of volumetrically characterising the subsurface expression of both site scale (tens of metres) geological structure, and finer (metre to sub-metre) scale earth-flow related structures. Petrophysical analysis of the borehole core samples is used to develop relationships between the electrical and physical formation properties, to aid calibration and interpretation of 3D ERT images. Results of the landslide investigation reveal that an integrated approach centred on volumetric geophysical imaging successfully achieves a detailed understanding of structure and lithology of a complex landslide system, which cannot be achieved through the use of remotely sensed data or discrete intrusive sampling alone

Thermocapillary actuation of liquid flow on chemically patterned surfaces

We have investigated the thermocapillary flow of a Newtonian liquid on hydrophilic microstripes which are lithographically defined on a hydrophobic surface. The speed of the microstreams is studied as a function of the stripe width w, the applied thermal gradient |dT/dx| and the liquid volume V deposited on a connecting reservoir pad. Numerical solutions of the flow speed as a function of downstream position show excellent agreement with experiment. The only adjustable parameter is the inlet film height, which is controlled by the ratio of the reservoir pressure to the shear stress applied to the liquid stream. In the limiting cases where this ratio is either much smaller or much larger than unity, the rivulet speed shows a power law dependency on w, |dT/dx| and V. In this study we demonstrate that thermocapillary driven flow on chemically patterned surfaces can provide an elegant and tunable method for the transport of ultrasmall liquid volumes in emerging microfluidic technologies

Climate change and crop diversity: farmers’ perceptions and adaptation on the Bolivian Altiplano

Crop diversity is central to traditional risk management practices on the Andean Altiplano and may find renewed importance in adapting to climate change. This study explored the role of crop diversity in farmers’ adaptation actions in eight Aymara communities on the northern Bolivian Altiplano. Using a combination of quantitative and qualitative methods, including multifactor analysis and a community resilience self-assessment, we investigated how farmers’ use of diversity in adaptation is related to their perceptions of crop and variety tolerances and other environmental, social, and economic factors. Few crops and varieties were perceived as tolerant to increasingly intense and unpredictable drought, frost, hail, and pest and disease outbreaks. Some local crops and varieties were perceived as vulnerable to emerging conditions (e.g. oca, papalisa, isaño), whereas bitter potatoes and wild relatives of quinoa and cañahua were perceived as highly stress tolerant and provide food in harsh periods. A total 19% of households surveyed (N = 193) had introduced new crops or varieties—often disease resistant or early maturing—as an adaptive action. Introduction of commercial crops was a common adaptation action, reflecting farmers’ response to warming temperatures and changing economic opportunities, but greater sensitivity of the introduced crops may cause maladaptation. Despite intensification of cropping systems, households continue to maintain a median four potato varieties with different tolerance traits, yet this risk management practice was not perceived as adaptation. Strengthening resilience will require a combination of actions, including maintaining and expanding crop portfolios and restoring soil and ecosystem health, using both traditional and innovative approaches

Towards a better understanding of custodian farmers and their roles: insights from a case study in Cachilaya, Bolivia.

This publication is the result of a research collaboration between Bioversity International and the Fundación para la Promoción e Investigación de Productos Andinos (PROINPA). It deals with issues regarding on-farm conservation of agrobiodiversity, which is a poorly addressed field of research in spite of its pivotal role in the maintenance of global crop diversity. Strategic actors in on-farm conservation are those farmers who, for various reasons, distinguish themselves from others by their contribution to conserving crop diversity. We call them ‘custodian famers’, even though the terminology may not be suitable to all social contexts. Understanding who these custodian farmers are, their presence over the territory, the types of crops they maintain, why and how, as well as gaining insights on the cultural, social and economic drivers behind their efforts is, for scientists, a very important step in devising effective on-farm conservation strategies and this booklet is a contribution in that direction. The open-ended interviews and participant observation methodologies provided in this study are helpful in guiding future methodological approaches and advancing our understanding of how the roles of custodian farmers can be better recognized, harnessed and supported by society. This work has been carried out in the framework of a major global UN Project supported by IFAD and the European Commission, which is focusing on the development of innovative participatory approaches for the conservation of neglected and underutilized species (NUS) on farm

Lung CD8+ T cells in COPD have increased expression of bacterial TLRs

Abstract Background Toll-like receptors (TLRs) on T cells can modulate their responses, however, the extent and significance of TLR expression by lung T cells, NK cells, or NKT cells in chronic obstructive pulmonary disease (COPD) is unknown. Methods Lung tissue collected from clinically-indicated resections (n = 34) was used either: (a) to compare the expression of TLR1, TLR2, TLR2/1, TLR3, TLR4, TLR5, TLR6 and TLR9 on lung CD8+ T cells, CD4+ T cells, NK cells and NKT cells from smokers with or without COPD; or (b) to isolate CD8+ T cells for culture with anti-CD3ε without or with various TLR ligands. We measured protein expression of IFN-γ, TNF-α, IL-13, perforin, granzyme A, granzyme B, soluble FasL, CCL2, CCL3, CCL4, CCL5, CCL11, and CXCL9 in supernatants. Results All the lung subsets analyzed demonstrated low levels of specific TLR expression, but the percentage of CD8+ T cells expressing TLR1, TLR2, TLR4, TLR6 and TLR2/1 was significantly increased in COPD subjects relative to those without COPD. In contrast, from the same subjects, only TLR2/1 and TLR2 on lung CD4+ T cells and CD8+ NKT cells, respectively, showed a significant increase in COPD and there was no difference in TLR expression on lung CD56+ NK cells. Production of the Tc1 cytokines IFN-γ and TNF-α by lung CD8+ T cells were significantly increased via co-stimulation by Pam3CSK4, a specific TLR2/1 ligand, but not by other agonists. Furthermore, this increase in cytokine production was specific to lung CD8+ T cells from patients with COPD as compared to lung CD8+ T cells from smokers without COPD. Conclusions These data suggest that as lung function worsens in COPD, the auto-aggressive behavior of lung CD8+ T cells could increase in response to microbial TLR ligands, specifically ligands against TLR2/1.http://deepblue.lib.umich.edu/bitstream/2027.42/112427/1/12931_2012_Article_1320.pd

Origin of Shifts in the Surface Plasmon Resonance Frequencies for Au and Ag Nanoparticles

Origin of shifts in the surface plasmon resonance (SPR) frequency for noble metal (Au, Ag) nanoclusters are discussed in this book chapter. Spill out of electron from the Fermi surface is considered as the origin of red shift. On the other hand, both screening of electrons of the noble metal in porous media and quantum effect of screen surface electron are considered for the observed blue shift in the SPR peak position.Comment: 37 pages, 14 Figures in the submitted book chapter of The Annual Reviews in Plasmonics, edited by Professor Chris D. Geddes. Springer Scinec

Effects of hydrogen in the annealing environment on photoluminescence from Si nanoparticles in SiO2

The role of hydrogen in enhancing the photoluminescence (PL) yield observed from Si nanocrystals embedded in SiO{sub 2} has been studied. SiO{sub 2} thermal oxides and bulk fused silica samples have been implanted with Si and subsequently annealed in various ambients including hydrogen or deuterium forming gases (Ar+4%H{sub 2} or Ar+4%D{sub 2}) or pure Ar. Results are presented for annealing at temperatures between 200 and 1100 C. Depth and concentration profiles of H and D at various stages of processing have been measured using elastic recoil detection. Hydrogen or deuterium is observed in the bulk after annealing in forming gas but not after high temperature (1100 C) anneals in Ar. The presence of hydrogen dramatically increases the broad PL band centered in the near-infrared after annealing at 1100 C but has almost no effect on the PL spectral distribution. Hydrogen is found to selectively trap in the region where Si nanocrystals are formed, consistent with a model of H passivating surface states at the Si/SiO{sub 2} interface that leads to enhanced PL. The thermal stability of the trapped H and the PL yield observed after a high temperature anneal have been studied. The hydrogen concentration and PL yield are unchanged for subsequent anneals up to 400 C. However, above 400 C the PL decreases and a more complicated H chemistry is evident. Similar concentrations of H or D are trapped after annealing in H{sub 2} or D{sub 2} forming gas; however, no differences in the PL yield or spectral distribution are observed, indicating that the electronic transitions resulting in luminescence are not dependent on the mass of the hydrogen species

Basal Gene Expression by Lung CD4+ T Cells in Chronic Obstructive Pulmonary Disease Identifies Independent Molecular Correlates of Airflow Obstruction and Emphysema Extent

Lung CD4+ T cells accumulate as chronic obstructive pulmonary disease (COPD) progresses, but their role in pathogenesis remains controversial. To address this controversy, we studied lung tissue from 53 subjects undergoing clinically-indicated resections, lung volume reduction, or transplant. Viable single-cell suspensions were analyzed by flow cytometry or underwent CD4+ T cell isolation, followed either by stimulation with anti-CD3 and cytokine/chemokine measurement, or by real-time PCR analysis. In lung CD4+ T cells of most COPD subjects, relative to lung CD4+ T cells in smokers with normal spirometry: (a) stimulation induced minimal IFN-γ or other inflammatory mediators, but many subjects produced more CCL2; (b) the T effector memory subset was less uniformly predominant, without correlation with decreased IFN-γ production. Analysis of unstimulated lung CD4+ T cells of all subjects identified a molecular phenotype, mainly in COPD, characterized by markedly reduced mRNA transcripts for the transcription factors controlling TH1, TH2, TH17 and FOXP3+ T regulatory subsets and their signature cytokines. This mRNA-defined CD4+ T cell phenotype did not result from global inability to elaborate mRNA; increased transcripts for inhibitory CD28 family members or markers of anergy; or reduced telomerase length. As a group, these subjects had significantly worse spirometry, but not DLCO, relative to subjects whose lung CD4+ T cells expressed a variety of transcripts. Analysis of mRNA transcripts of unstimulated lung CD4+ T cell among all subjects identified two distinct molecular correlates of classical COPD clinical phenotypes: basal IL-10 transcripts correlated independently and inversely with emphysema extent (but not spirometry); by contrast, unstimulated IFN-γ transcripts correlated independently and inversely with reduced spirometry (but not reduced DLCO or emphysema extent). Aberrant lung CD4+ T cells polarization appears to be common in advanced COPD, but also exists in some smokers with normal spirometry, and may contribute to development and progression of specific COPD phenotypes. Trial Registration ClinicalTrials.gov as NCT0028122

Can CAPTURE Be Used to Identify Undiagnosed Patients with Mild-To-Moderate COPD Likely to Benefit from Treatment?

Background: COPD Assessment in Primary Care To Identify Undiagnosed Respiratory Disease and Exacerbation Risk (CAPTURE™) uses five questions and peak expiratory flow (PEF) thresholds (males ≤350 L/min; females ≤250 L/min) to identify patients with a forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC)11 60%–80% predicted) who may also benefit from diagnosis and treatment. Methods: Data from the CAPTURE development study were used to test its sensitivity (SN) and specificity (SP) differentiating mild-to-moderate COPD (n=73) from no COPD (n=87). SN and SP for differentiating all COPD cases (mild to severe; n=259) from those without COPD (n=87) were also estimated. The modified Medical Research Council (mMRC) dyspnea scale and COPD Assessment Test (CAT™) were used to evaluate symptoms and health status. Clinical Trial Registration: NCT01880177, https://ClinicalTrials.gov/ct2/show/NCT01880177?term=NCT01880177&rank=1. Results: Mean age (+SD): 61 (+10.5) years; 41% male. COPD: FEV1/FVC=0.60 (+0.1), FEV1% predicted=74% (+12.4). SN and SP for differentiating mild-to-moderate and non-COPD patients (n=160): Questionnaire: 83.6%, 67.8%; PEF (≤450 L/min; ≤350 L/min): 83.6%, 66.7%; CAPTURE (Questionnaire+PEF): 71.2%, 83.9%. COPD patients whose CAPTURE results suggested that diagnostic evaluation was warranted (n=52) were more likely to be symptomatic than patients whose results did not (n=21) (mMRC \u3e2: 37% vs 5%, p10: 86% vs 57%, p Conclusion: CAPTURE (450/350) may be useful for identifying symptomatic patients with mild-to-moderate airflow obstruction in need of diagnostic evaluation for COPD