The Horizontal Ice Nucleation Chamber (HINC) : INP measurements at conditions relevant for mixed-phase clouds at the High Altitude Research Station Jungfraujoch

In this work we describe the Horizontal Ice Nucleation Chamber (HINC) as a new instrument to measure ambient ice-nucleating particle (INP) concentrations for conditions relevant to mixed-phase clouds. Laboratory verification and validation experiments confirm the accuracy of the thermodynamic conditions of temperature (T) and relative humidity (RH) in HINC with uncertainties in T of ±0.4 K and in RH with respect to water (RHw) of ±1.5 %, which translates into an uncertainty in RH with respect to ice (RHi) of ±3.0 % at T > 235 K. For further validation of HINC as a field instrument, two measurement campaigns were conducted in winters 2015 and 2016 at the High Altitude Research Station Jungfraujoch (JFJ; Switzerland, 3580 m a. s. l. ) to sample ambient INPs. During winters 2015 and 2016 the site encountered free-tropospheric conditions 92 and 79 % of the time, respectively. We measured INP concentrations at 242 K at water-subsaturated conditions (RHw = 94 %), relevant for the formation of ice clouds, and in the water-supersaturated regime (RHw = 104 %) to represent ice formation occurring under mixed-phase cloud conditions. In winters 2015 and 2016 the median INP concentrations at RHw = 94 % was below the minimum detectable concentration. At RHw = 104 %, INP concentrations were an order of magnitude higher, with median concentrations in winter 2015 of 2.8 per standard liter (std L−1; normalized to standard T of 273 K and pressure, p, of 1013 hPa) and 4.7 std L−1 in winter 2016. The measurements are in agreement with previous winter measurements obtained with the Portable Ice Nucleation Chamber (PINC) of 2.2 std L−1 at the same location. During winter 2015, two events caused the INP concentrations at RHw = 104 % to significantly increase above the campaign average. First, an increase to 72.1 std L−1 was measured during an event influenced by marine air, arriving at the JFJ from the North Sea and the Norwegian Sea. The contribution from anthropogenic or other sources can thereby not be ruled out. Second, INP concentrations up to 146.2 std L−1 were observed during a Saharan dust event. To our knowledge this is the first time that a clear enrichment in ambient INP concentration in remote regions of the atmosphere is observed during a time of marine air mass influence, suggesting the importance of marine particles on ice nucleation in the free troposphere

Contenido de aceite en pasta de aceituna sobre una base de peso seco (OPDW): un indicador del tiempo de cosecha óptimo en modernos olivares

In modern oil olive orchards, mechanical harvesting technologies have significantly accelerated harvesting outputs, thereby allowing for careful planning of harvest timing. While optimizing harvest time may have profound effects on oil yield and quality, the necessary tools to precisely determine the best date are rather scarce. For instance, the commonly used indicator, the fruit ripening index, does not necessarily correlate with oil accumulation. Oil content per fruit fresh weight is strongly affected by fruit water content, making the ripening index an unreliable indicator. However, oil in the paste, calculated on a dry weight basis (OPDW), provides a reliable indication of oil accumulation in the fruit. In most cultivars tested here, OPDW never exceeded ca. 0.5 g.g–1 dry weight, making this threshold the best indicator for the completion of oil accumulation and its consequent reduction in quality thereafter. The rates of OPDW and changes in quality parameters strongly depend on local conditions, such as climate, tree water status and fruit load. We therefore propose a fast and easy method to determine and monitor the OPDW in a given orchard. The proposed method is a useful tool for the determination of optimal harvest timing, particularly in large plots under intensive cultivation practices, with the aim of increasing orchard revenues. The results of this research can be directly applied in olive orchards, especially in large-scale operations. By following the proposed method, individual plots can be harvested according to sharp thresholds of oil accumulation status and pre-determined oil quality parameters, thus effectively exploiting the potentials of oil yield and quality. The method can become a powerful tool for scheduling the harvest throughout the season, and at the same time forecasting the flow of olives to the olive mill.En los modernos olivares, las tecnologías de recogida mecánica han acelerado significativamente la recogida de las cosechas, lo que permite la planificación del momento idóneo de la cosecha. Mientras que la optimización de tiempo de cosecha puede tener importantes efectos en la producción de un aceite de calidad, las herramientas para determinar con precisión la mejor fecha de la cosecha son más bien pobres. Por ejemplo, el indicador de uso común, el índice de maduración de la fruta, no se correlaciona necesariamente con la acumulación de aceite. El contenido de aceite por peso de fruto fresco está estrechamente afectado por el contenido de agua de la fruta, por lo que es un indicador poco fiable. Sin embargo, el aceite en la pasta, calculado sobre una base de peso seco (OPDW), proporciona una indicación fiable de la acumulación de aceite en el fruto. En la mayoría de los cultivares analizados aquí, OPDW nunca excedió 0.5 g·g–1 de peso seco, haciendo de este umbral el mejor indicador para la terminación de la acumulación de aceite y su consiguiente reducción de la calidad. Las tasas de OPDW y los cambios en los parámetros de calidad dependen en gran medida de las condiciones locales, como el clima, el estado hídrico del árbol, y la carga frutal. Por tanto, proponemos un método rápido y fácil de determinar y seguir OPDW en un olivar determinado. El método propuesto es una herramienta útil para la determinación del momento óptimo de cosecha, especialmente en las grandes parcelas bajo prácticas intensivas de cultivo, y con el consiguiente aumento de ingresos. Los resultados de esta investigación pueden aplicarse directamente a un olivar, especialmente en operaciones a gran escala. Siguiendo el método propuesto, las parcelas individuales pueden cosecharse de acuerdo con los perfiles de estado de acumulación de aceite y determinados parámetros de calidad del aceite, por lo tanto explotar eficazmente los potenciales de rendimiento de aceite y calidad. El método puede convertirse en una poderosa herramienta de programar la cosecha a lo largo de la temporada, la previsión de este modo el flujo de las aceitunas a la almazara

The Horizontal Ice Nucleation Chamber (HINC): INP measurements at conditions relevant for mixed-phase clouds at the High Altitude Research Station Jungfraujoch

Abstract. In this work we describe the Horizontal Ice Nucleation Chamber, HINC as a new instrument to measure ambient ice nucleating particle (INP) concentrations for conditions relevant to mixed-phase clouds. Laboratory verification and validation experiments confirm accuracy of the thermodynamic conditions of temperature (T) and relative humidity (RH) in HINC with uncertainties in temperature of ±0.4 K and in RH with respect to water (RHw) of ±1.5 %, which translates to an uncertainty in RH with respect to ice (RHi) of ±3.0 % at T &gt; 235 K. For further validation of HINC as a field instrument, two measurement campaigns were conducted in winters 2015 and 2016 at the High Altitude Research Station Jungfraujoch (JFJ; Switzerland, 3580 m a.s.l.) to sample ambient INPs. During winters 2015 and 2016 the site encountered free tropospheric conditions 92 % and 79 % of the time respectively. We measured INP concentrations at 242 K at water sub-saturated conditions (RHw = 94 %), relevant for the formation of ice clouds, and in the water supersaturated regime (RHw = 103–104 %) to represent ice formation occurring under mixed-phase cloud conditions. In winter 2015 and 2016 the median INP concentrations at RHw = 94 % was below the minimum detectable concentration. At RHw = 104 %, INP concentrations were an order of magnitude higher, with median concentrations in winter 2015 of 2.8 per standard liter (stdL−1; normalized to standard temperature T = 273 K and pressure p = 1013 hPa) and 4.7 stdL−1 in winter 2016. The measurements are in agreement with previous winter measurements obtained with the Portable Ice Nucleation Chamber, PINC, of 2.2 stdL−1 at the same location. During winter 2015, two events caused the INP concentrations at RHw = 103–104 % to significantly increase above the campaign average. First, an increase to 72.1 stdL−1 was measured during an event influenced by marine air, coming from the Northern Sea and the Norwegian Sea. Second, INP concentrations up to 146.2 stdL−1 were observed during a Saharan dust event. To our knowledge this is the first time that a clear enrichment in ambient INP concentration is observed during a time of marine air mass influence, indicating the importance of marine particles on ice nucleation in the free troposphere. </jats:p

The Hemopoietic Stem Cell Niche Versus the Microenvironment of the Multiple Myeloma-Tumor Initiating Cell

Multiple myeloma cells are reminiscent of hemopoietic stem cells in their strict dependence upon the bone marrow microenvironment. However, from all other points of view, multiple myeloma cells differ markedly from stem cells. The cells possess a mature phenotype and secrete antibodies, and have thus made the whole journey to maturity, while maintaining a tumor phenotype. Not much credence was given to the possibility that the bulk of plasma-like multiple myeloma tumor cells is generated from tumor-initiating cells. Although interleukin-6 is a major contributor to the formation of the tumor’s microenvironment in multiple myeloma, it is not a major factor within hemopoietic stem cell niches. The bone marrow niche for myeloma cells includes the activity of inflammatory cytokines released through osteoclastogenesis. These permit maintenance of myeloma cells within the bone marrow. In contrast, osteoclastogenesis constitutes a signal that drives hemopoietic stem cells away from their bone marrow niches. The properties of the bone marrow microenvironment, which supports myeloma cell maintenance and proliferation, is therefore markedly different from the characteristics of the hemopoietic stem cell niche. Thus, multiple myeloma presents an example of a hemopoietic tumor microenvironment that does not resemble the corresponding stem cell renewal niche

Background Free‐Tropospheric Ice Nucleating Particle Concentrations at Mixed‐Phase Cloud Conditions

Clouds containing ice are vital for precipitation formation and are important in determining the Earths radiative budget. However primary formation of ice in clouds is not fully understood. In the presence of ice nucleating particles (INPs), the phase change to ice is promoted, but identification and quantification of INPs in a natural environment remains challenging because of their low numbers. In this paper we quantify INP number concentrations in the free troposphere (FT) as measured at the High Altitude Research Station Jungfraujoch during the years 2014 to 2017. INPs were measured at conditions relevant for mixed-phase cloud formation at 241 to 242 K

Arrested neural and advanced mesenchymal differentiation of glioblastoma cells-comparative study with neural progenitors

<p>Abstract</p> <p>Background</p> <p>Although features of variable differentiation in glioblastoma cell cultures have been reported, a comparative analysis of differentiation properties of normal neural GFAP positive progenitors, and those shown by glioblastoma cells, has not been performed.</p> <p>Methods</p> <p>Following methods were used to compare glioblastoma cells and GFAP+NNP (NHA): exposure to neural differentiation medium, exposure to adipogenic and osteogenic medium, western blot analysis, immunocytochemistry, single cell assay, BrdU incorporation assay. To characterize glioblastoma cells <it>EGFR </it>amplification analysis, LOH/MSI analysis, and <it>P53 </it>nucleotide sequence analysis were performed.</p> <p>Results</p> <p><it>In vitro </it>differentiation of cancer cells derived from eight glioblastomas was compared with GFAP-positive normal neural progenitors (GFAP+NNP). Prior to exposure to differentiation medium, both types of cells showed similar multilineage phenotype (CD44+/MAP2+/GFAP+/Vimentin+/Beta III-tubulin+/Fibronectin+) and were positive for SOX-2 and Nestin. In contrast to GFAP+NNP, an efficient differentiation arrest was observed in all cell lines isolated from glioblastomas. Nevertheless, a subpopulation of cells isolated from four glioblastomas differentiated after serum-starvation with varying efficiency into derivatives indistinguishable from the neural derivatives of GFAP+NNP. Moreover, the cells derived from a majority of glioblastomas (7 out of 8), as well as GFAP+NNP, showed features of mesenchymal differentiation when exposed to medium with serum.</p> <p>Conclusion</p> <p>Our results showed that stable co-expression of multilineage markers by glioblastoma cells resulted from differentiation arrest. According to our data up to 95% of glioblastoma cells can present <it>in vitro </it>multilineage phenotype. The mesenchymal differentiation of glioblastoma cells is advanced and similar to mesenchymal differentiation of normal neural progenitors GFAP+NNP.</p

Statistical Modeling of Single Target Cell Encapsulation

High throughput drop-on-demand systems for separation and encapsulation of individual target cells from heterogeneous mixtures of multiple cell types is an emerging method in biotechnology that has broad applications in tissue engineering and regenerative medicine, genomics, and cryobiology. However, cell encapsulation in droplets is a random process that is hard to control. Statistical models can provide an understanding of the underlying processes and estimation of the relevant parameters, and enable reliable and repeatable control over the encapsulation of cells in droplets during the isolation process with high confidence level. We have modeled and experimentally verified a microdroplet-based cell encapsulation process for various combinations of cell loading and target cell concentrations. Here, we explain theoretically and validate experimentally a model to isolate and pattern single target cells from heterogeneous mixtures without using complex peripheral systems.Wallace H. Coulter Foundation (Young Investigator in Bioengineering Award)National Institutes of Health (U.S.) (Grant R01AI081534)National Institutes of Health (U.S.) (Grant R21AI087107

Innate Killing of Leishmania donovani by Macrophages of the Splenic Marginal Zone Requires IRF-7

Highly phagocytic macrophages line the marginal zone (MZ) of the spleen and the lymph node subcapsular sinus. Although these macrophages have been attributed with a variety of functions, including the uptake and clearance of blood and lymph-borne pathogens, little is known about the effector mechanisms they employ after pathogen uptake. Here, we have combined gene expression profiling and RNAi using a stromal macrophage cell line with in situ analysis of the leishmanicidal activity of marginal zone macrophages (MZM) and marginal metallophilic macrophages (MMM) in wild type and gene targeted mice. Our data demonstrate a critical role for interferon regulatory factor-7 (IRF-7) in regulating the killing of intracellular Leishmania donovani by these specialised splenic macrophage sub-populations. This study, therefore, identifies a new role for IRF-7 as a regulator of innate microbicidal activity against this, and perhaps other, non-viral intracellular pathogens. This study also highlights the importance of selecting appropriate macrophage populations when studying pathogen interactions with this functionally diverse lineage of cells

Human bone marrow mesenchymal stem cells : a systematic reappraisal via the genostem experience

Genostem (acronym for “Adult mesenchymal stem cells engineering for connective tissue disorders. From the bench to the bed side”) has been an European consortium of 30 teams working together on human bone marrow Mesenchymal Stem Cell (MSC) biological properties and repair capacity. Part of Genostem activity has been dedicated to the study of basic issues on undifferentiated MSCs properties and on signalling pathways leading to the differentiation into 3 of the connective tissue lineages, osteoblastic, chondrocytic and tenocytic. We have evidenced that native bone marrow MSCs and stromal cells, forming the niche of hematopoietic stem cells, were the same cellular entity located abluminally from marrow sinus endothelial cells. We have also shown that culture-amplified, clonogenic and highly-proliferative MSCs were bona fide stem cells, sharing with other stem cell types the major attributes of self-renewal and of multipotential priming to the lineages to which they can differentiate (osteoblasts, chondrocytes, adipocytes and vascular smooth muscle cells/pericytes). Extensive transcription profiling and in vitro and in vivo assays were applied to identify genes involved in differentiation. Thus we have described novel factors implicated in osteogenesis (FHL2, ITGA5, Fgf18), chondrogenesis (FOXO1A) and tenogenesis (Smad8). Another part of Genostem activity has been devoted to studies of the repair capacity of MSCs in animal models, a prerequisite for future clinical trials. We have developed novel scaffolds (chitosan, pharmacologically active microcarriers) useful for the repair of both bone and cartilage. Finally and most importantly, we have shown that locally implanted MSCs effectively repair bone, cartilage and tendonWork supported by the European Community (Key action 1.2.4-3 Integrated Project Genostem, contract No 503161)

The maize root stem cell niche: a partnership between two sister cell populations

Using transcript profile analysis, we explored the nature of the stem cell niche in roots of maize (Zea mays). Toward assessing a role for specific genes in the establishment and maintenance of the niche, we perturbed the niche and simultaneously monitored the spatial expression patterns of genes hypothesized as essential. Our results allow us to quantify and localize gene activities to specific portions of the niche: to the quiescent center (QC) or the proximal meristem (PM), or to both. The data point to molecular, biochemical and physiological processes associated with the specification and maintenance of the niche, and include reduced expression of metabolism-, redox- and certain cell cycle-associated transcripts in the QC, enrichment of auxin-associated transcripts within the entire niche, controls for the state of differentiation of QC cells, a role for cytokinins specifically in the PM portion of the niche, processes (repair machinery) for maintaining DNA integrity and a role for gene silencing in niche stabilization. To provide additional support for the hypothesized roles of the above-mentioned and other transcripts in niche specification, we overexpressed, in Arabidopsis, homologs of representative genes (eight) identified as highly enriched or reduced in the maize root QC. We conclude that the coordinated changes in expression of auxin-, redox-, cell cycle- and metabolism-associated genes suggest the linkage of gene networks at the level of transcription, thereby providing additional insights into events likely associated with root stem cell niche establishment and maintenance