Determination of respiratory gas flow by electrical impedance tomography in an animal model of mechanical ventilation

Background A recent method determines regional gas flow of the lung by electrical impedance tomography (EIT). The aim of this study is to show the applicability of this method in a porcine model of mechanical ventilation in healthy and diseased lungs. Our primary hypothesis is that global gas flow measured by EIT can be correlated with spirometry. Our secondary hypothesis is that regional analysis of respiratory gas flow delivers physiologically meaningful results. Methods In two sets of experiments n = 7 healthy pigs and n = 6 pigs before and after induction of lavage lung injury were investigated. EIT of the lung and spirometry were registered synchronously during ongoing mechanical ventilation. In-vivo aeration of the lung was analysed in four regions-of-interest (ROI) by EIT: 1) global, 2) ventral (non-dependent), 3) middle and 4) dorsal (dependent) ROI. Respiratory gas flow was calculated by the first derivative of the regional aeration curve. Four phases of the respiratory cycle were discriminated. They delivered peak and late inspiratory and expiratory gas flow (PIF, LIF, PEF, LEF) characterizing early or late inspiration or expiration. Results Linear regression analysis of EIT and spirometry in healthy pigs revealed a very good correlation measuring peak flow and a good correlation detecting late flow. PIFEIT = 0.702 · PIFspiro + 117.4, r2 = 0.809; PEFEIT = 0.690 · PEFspiro-124.2, r2 = 0.760; LIFEIT = 0.909 · LIFspiro + 27.32, r2 = 0.572 and LEFEIT = 0.858 · LEFspiro-10.94, r2 = 0.647. EIT derived absolute gas flow was generally smaller than data from spirometry. Regional gas flow was distributed heterogeneously during different phases of the respiratory cycle. But, the regional distribution of gas flow stayed stable during different ventilator settings. Moderate lung injury changed the regional pattern of gas flow. Conclusions We conclude that the presented method is able to determine global respiratory gas flow of the lung in different phases of the respiratory cycle. Additionally, it delivers meaningful insight into regional pulmonary characteristics, i.e. the regional ability of the lung to take up and to release air.

Redistribution and attitudes toward immigrants: A European perspective

We investigate whether the dependence of immigrants on welfare benefits leads to opposition to further immigration by natives and immigrants in a pooled cross-section of 21 European countries for the 2004{2010 period. Explicitly controlling for the dependence of immigrants and natives on benefits we find that higher benefit take-up rates among immigrants than among natives lead to less favourable attitudes of natives towards immigration. Interestingly, we do not find similar stylised facts for immigrants' attitudes towards immigration.

The impact of welfare benefits on natives' and immigrants' attitudes towards immigration

We investigate whether the dependence of immigrants on welfare benefits leads to opposition to further immigration by natives and immigrants in a pooled cross-section of 21 European countries for the 2004-2010 period. Explicitly controlling for the dependence of immigrants and natives on benefits we find that higher benefit take-up rates among immigrants than among natives lead to less favourable attitudes of natives towards immigration. Interestingly, we do not find similar stylised facts for immigrants' attitudes towards immigration.

Redistribution and attitudes toward immigrants: A European perspective

We investigate whether the dependence of immigrants on welfare benefits leads to opposition to further immigration by natives and immigrants in a pooled cross-section of 21 European countries for the 2004-2010 period. Explicitly controlling for the dependence of immigrants and natives on benefits we find that higher benefit take-up rates among immigrants than among natives lead to less favourable attitudes of natives towards immigration. Interestingly, we do not find similar stylised facts for immigrants' attitudes towards immigration.

The impact of welfare benefits on natives' and immigrants' attitudes towards immigration

We investigate whether the dependence of immigrants on welfare benefits leads to opposition to further immigration by natives and immigrants in a pooled cross-section of 21 European countries for the 2004-2010 period. Explicitly controlling for the dependence of immigrants and natives on benefits we find that higher benefit take-up rates among immigrants than among natives lead to less favourable attitudes of natives towards immigration. Interestingly, we do not find similar stylised facts for immigrants' attitudes towards immigration.

Sequestration of plant secondary metabolites by insect herbivores: molecular mechanisms and ecological consequences

Numerous insect herbivores can take up and store plant toxins as self-defense against their own natural enemies. Plant toxin sequestration is tightly linked with tolerance strategies that keep the toxins functional. Specific transporters have been identified that likely allow the herbivore to control the spatiotemporal dynamics of toxin accumulation. Certain herbivores furthermore possess specific enzymes to boost the bioactivity of the sequestered toxins. Ecologists have studied plant toxin sequestration for decades. The recently uncovered molecular mechanisms in combination with transient, non-transgenic systems to manipulate insect gene expression will help to understand the importance of toxin sequestration for food-web dynamics in nature.

Plant diversity moderates drought stress in grasslands: Implications from a large real-world study on 13C natural abundances

Land-use change and intensification play a key role in the current biodiversity crisis. The resulting species loss can have severe effects on ecosystem functions and services, thereby increasing ecosystem vulnerability to climate change. We explored whether land-use intensification (i.e. fertilization intensity), plant diversity and other potentially confounding environmental factors may be significantly related to water use (i.e. drought stress) of grassland plants. Drought stress was assessed using δ13C abundances in aboveground plant biomass of 150 grassland plots across a gradient of land-use intensity. Under water shortage, plants are forced to increasingly take up the heavier 13C due to closing stomata leading to an enrichment of 13C in biomass. Plants were sampled at the community level and for single species, which belong to three different functional groups (one grass, one herb, two legumes). Results show that plant diversity was significantly related to the δ13C signal in community, grass and legume biomass indicating that drought stress was lower under higher diversity, although this relation was not significant for the herb species under study. Fertilization, in turn, mostly increased drought stress as indicated by more positive δ13C values. This effect was mostly indirect by decreasing plant diversity. In line with these results, we found similar patterns in the δ13C signal of the organic matter in the topsoil, indicating a long history of these processes. Our study provided strong indication for a positive biodiversity-ecosystem functioning relationship with reduced drought stress at higher plant diversity. However, it also underlined a negative reinforcing situation: as land-use intensification decreases plant diversity in grasslands, this might subsequently increases drought sensitivity. Vice-versa, enhancing plant diversity in species-poor agricultural grasslands may moderate negative effects of future climate change.

Schumpeter and Personal Capitalism

In an earlier paper, I criticized Schumpeter's account of the obsolescence of the entrepreneur in Capitalism, Socialism, and Democracy. That account rests, I argued, on a confusion about the nature of scientific knowledge and its role in the competences of the firm. This paper is an attempt to take up the argument again, moving it away from the doctrine-historical into the provinces of the economics of organization. Drawing on the work of Max Weber, as well as on a case study of the Swiss watch industry, the paper argues for the ineradicable role of personal capitalism, properly understood.

Cellular Uptake of Neutrohpil Elastase Links Inflammation to Adaptive Immunity

Many tumors arise from sites of inflammation providing evidence that innate immunity is a critical component in the development and progression of cancer. Neutrophils are primary mediators of the innate immune response. Upon activation, an important function of neutrophils is release of an assortment of proteins from their granules including the serine protease neutrophil elastase (NE). The effect of NE on cancer has been attributed primarily to its ability to degrade the extracellular matrix thereby promoting invasion and metastasis. Recently, it was shown that NE could be taken up by lung cancer cells leading to degradation of insulin receptor substrate-1 thereby promoting hyperactivity of the phosphatidylinositol-3 kinase (PI3K) pathway and tumor cell proliferation. To our knowledge, nobody has investigated uptake of NE by other tumor types. In addition, NE has broad substrate specificity suggesting that uptake of NE by tumor cells could impact processes regulating tumorigenensis other than activation of the PI3K pathway. Neutrophil elastase has been identified in breast cancer specimens where high levels of NE have prognostic significance. These studies have assessed NE levels in whole tumor lysates. Because the major source of NE is from activated neutrophils, we hypothesized that breast cancer cells do not have endogenous NE but may take up NE released by tumor associated neutrophils in the tumor microenvironment and that this could provide a link between the innate immune response to tumors and specific adaptive immune responses. In this thesis, we show that breast cancer cells lack endogenous NE expression and that they are able to take up NE resulting in increased generation of low molecular weight cyclin E (CCNE) and enhanced susceptibility to lysis by CCNE-specific cytotoxic T lymphocytes. We also show that after taking up NE and proteinase 3 (PR3), a second primary granule protease with significant homology to NE, breast cancer cells cross-present the NE- and PR3-derived peptide PR1 rendering them susceptible to PR1-targeted therapies. Taken together, our data support a role for NE uptake in modulating adaptive immune responses against breast cancer.

Análisis y pautas para el mejoramiento socioeconómico de los productores del oeste pampeano

En la zona comprendida entre las isoyetas de 500 mm a 300 mm, perteneciente a la provincia fitogeográfica del Monte, una población rural de 6.845 habitantes, 9 del total provincial, con una densidad de 0,2 hab /km2, habita los cinco departamentos del centro y extremo oeste de La Pampa, cuya superficie abarca el 38 de la provincia. Su economía de subsistencia se desarrolla sobre campos naturales, con una ganadería de bovinos, caprinos, ovinos y equinos. La población presenta un alto grado de dispersión y un significativo aislamiento respecto de los centros más poblados. El objetivo a cumplir, modificar las condiciones de vida de los "crianceros", hace necesaria la aplicación de pautas que permitan convertir estas economías de subsistencia en pequeños emprendimientos ganaderos con aceptables índices de rentabilidad mediante el uso más eficiente del medio y sus recursos. Esta estructura productiva ha de permitir una relación más solidaria entre los ganaderos, una mayor libertad en la toma de decisiones y una mayor independencia económica. La consolidación estable de este proyecto y el logro de sus objetivos redundarán en un mejor manejo del ecosistema, así como en un marcado mejoramiento de la calidad de vida de estos alejados productores rurales.

Análisis y pautas para el mejoramiento socioeconómico de los productores del oeste pampeano

En la zona comprendida entre las isoyetas de 500 mm a 300 mm, perteneciente a la provincia fitogeográfica del Monte, una población rural de 6.845 habitantes, 9 del total provincial, con una densidad de 0,2 hab /km2, habita los cinco departamentos del centro y extremo oeste de La Pampa, cuya superficie abarca el 38 de la provincia. Su economía de subsistencia se desarrolla sobre campos naturales, con una ganadería de bovinos, caprinos, ovinos y equinos. La población presenta un alto grado de dispersión y un significativo aislamiento respecto de los centros más poblados. El objetivo a cumplir, modificar las condiciones de vida de los "crianceros", hace necesaria la aplicación de pautas que permitan convertir estas economías de subsistencia en pequeños emprendimientos ganaderos con aceptables índices de rentabilidad mediante el uso más eficiente del medio y sus recursos. Esta estructura productiva ha de permitir una relación más solidaria entre los ganaderos, una mayor libertad en la toma de decisiones y una mayor independencia económica. La consolidación estable de este proyecto y el logro de sus objetivos redundarán en un mejor manejo del ecosistema, así como en un marcado mejoramiento de la calidad de vida de estos alejados productores rurales.

Análisis y pautas para el mejoramiento socioeconómico de los productores del oeste pampeano

En la zona comprendida entre las isoyetas de 500 mm a 300 mm, perteneciente a la provincia fitogeográfica del Monte, una población rural de 6.845 habitantes, 9 del total provincial, con una densidad de 0,2 hab /km2, habita los cinco departamentos del centro y extremo oeste de La Pampa, cuya superficie abarca el 38 de la provincia. Su economía de subsistencia se desarrolla sobre campos naturales, con una ganadería de bovinos, caprinos, ovinos y equinos. La población presenta un alto grado de dispersión y un significativo aislamiento respecto de los centros más poblados. El objetivo a cumplir, modificar las condiciones de vida de los "crianceros", hace necesaria la aplicación de pautas que permitan convertir estas economías de subsistencia en pequeños emprendimientos ganaderos con aceptables índices de rentabilidad mediante el uso más eficiente del medio y sus recursos. Esta estructura productiva ha de permitir una relación más solidaria entre los ganaderos, una mayor libertad en la toma de decisiones y una mayor independencia económica. La consolidación estable de este proyecto y el logro de sus objetivos redundarán en un mejor manejo del ecosistema, así como en un marcado mejoramiento de la calidad de vida de estos alejados productores rurales.

ATPase activity, proton gradients and proton secretion inhibition during experiments with Sepia officinalis and Sepioteuthis lessoniana

The constraints of an active life in a pelagic habitat led to numerous convergent morphological and physiological adaptations that enable cephalopod molluscs and teleost fishes to compete for similar resources. Here, we show for the first time that such convergent developments are also found in the ontogenetic progression of ion regulatory tissues; as in teleost fish, epidermal ionocytes scattered on skin and yolk sac of cephalopod embryos appear to be responsible for ionic and acid-base regulation before gill epithelia become functional. Ion and acid-base regulation is crucial in cephalopod embryos, as they are surrounded by a hypercapnic egg fluid with a Pco2 between 0.2 and 0.4 kPa. Epidermal ionocytes were characterized via immunohistochemistry, in situ hybridization, and vital dye-staining techniques. We found one group of cells that is recognized by concavalin A and MitoTracker, which also expresses Na+/H+ exchangers (NHE3) and Na+-K+-ATPase. Similar to findings obtained in teleosts, these NHE3-rich cells take up sodium in exchange for protons, illustrating the energetic superiority of NHE-based proton excretion in marine systems. In vivo electrophysiological techniques demonstrated that acid equivalents are secreted by the yolk and skin integument. Intriguingly, epidermal ionocytes of cephalopod embryos are ciliated as demonstrated by scanning electron microscopy, suggesting a dual function of epithelial cells in water convection and ion regulation. These findings add significant knowledge to our mechanistic understanding of hypercapnia tolerance in marine organisms, as it demonstrates that marine taxa, which were identified as powerful acid-base regulators during hypercapnic challenges, already exhibit strong acid-base regulatory abilities during embryogenesis.

(Table S1) Diatom abundance in coastal upwelling systems

Coastal upwelling systems account for approximately half of global ocean primary production and contribute disproportionately to biologically driven carbon sequestration. Diatoms, silica-precipitating microalgae, constitute the dominant phytoplankton in these productive regions, and their abundance and assemblage composition in the sedimentary record is considered one of the best proxies for primary production. The study of the sedimentary diatom abundance (SDA) and total organic carbon content (TOC) in the five most important coastal upwelling systems of the modern ocean (Iberia-Canary, Benguela, Peru-Humboldt, California and Somalia-Oman) reveals a global-scale positive relationship between diatom production and organic carbon burial. The analysis of SDA in conjunction with environmental variables of coastal upwelling systems such as upwelling strength, satellite-derived net primary production and surface water nutrient concentrations shows different relations between SDA and primary production on the regional scale. At the global-scale, SDA appears modulated by the capacity of diatoms to take up silicic acid, which ultimately sets an upper limit to global export production in these ocean regions.

Combined effects of CO2 and temperature on carbon uptake and partitioning by the marine diatoms Thalassiosira weissflogii and Dactyliosolen fragilissimus

Carbon uptake and partitioning of two globally abundant diatom species, Thalassiosira weissflogii and Dactyliosolen fragilissimus, was investigated in batch culture experiments under four conditions: ambient (15°C, 400 µatm), high CO2 (15°C, 1000 µatm), high temperature (20°C, 400 µatm), and combined (20°C, 1000 µatm). The experiments were run from exponential growth into the stationary phase (six days after nitrogen depletion), allowing us to track biogeochemical dynamics analogous to bloom situations in the ocean. Elevated CO2 had a fertilizing effect and enhanced uptake of dissolved inorganic carbon (DIC) by about 8% for T. weissflogii and by up to 39% for D. fragilissimus. This was also reflected in higher cell numbers, build-up of particulate and dissolved organic matter, and transparent exopolymer particles. The CO2 effects were most prominent in the stationary phase when nitrogen was depleted and CO2(aq) concentrations were low. This indicates that diatoms in the high CO2 treatments could take up more DIC until CO2 concentrations in seawater became so low that carbon limitation occurs. These results suggest that, contrary to common assumptions, diatoms could be highly sensitive to ongoing changes in oceanic carbonate chemistry, particularly under nutrient limitation. Warming from 15 to 20 °C had a stimulating effect on one species but acted as a stressor on the other species, highlighting the importance of species-specific physiological optima and temperature ranges in the response to ocean warming. Overall, these sensitivities to CO2 and temperature could have profound impacts on diatoms blooms and the biological pump.