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The identity of the dominant root-associated microbial symbionts in a forest determines the ability of trees to access limiting nutrients from atmospheric or soil pools1,2, sequester carbon3,4and withstand the effects of climate change5,6. Characterizing the global distribution of these symbioses and identifying the factors that control this distribution are thus integral to understanding the present and future functioning of forest ecosystems. Here we generate a spatially explicit global map of the symbiotic status of forests, using a database of over 1.1 million forest inventory plots that collectively contain over 28,000 tree species. Our analyses indicate that climate variables—in particular, climatically controlled variation in the rate of decomposition—are the primary drivers of the global distribution of major symbioses. We estimate that ectomycorrhizal trees, which represent only 2% of all plant species7, constitute approximately 60% of tree stems on Earth. Ectomycorrhizal symbiosis dominates forests in which seasonally cold and dry climates inhibit decomposition, and is the predominant form of symbiosis at high latitudes and elevation. By contrast, arbuscular mycorrhizal trees dominate in aseasonal, warm tropical forests, and occur with ectomycorrhizal trees in temperate biomes in which seasonally warm-and-wet climates enhance decomposition. Continental transitions between forests dominated by ectomycorrhizal or arbuscular mycorrhizal trees occur relatively abruptly along climate-driven decomposition gradients; these transitions are probably caused by positive feedback effects between plants and microorganisms. Symbiotic nitrogen fixers—which are insensitive to climatic controls on decomposition (compared with mycorrhizal fungi)—are most abundant in arid biomes with alkaline soils and high maximum temperatures. The climatically driven global symbiosis gradient that we document provides a spatially explicit quantitative understanding of microbial symbioses at the global scale, and demonstrates the critical role of microbial mutualisms in shaping the distribution of plant species. A spatially explicit global map of tree symbioses with nitrogen-fixing bacteria and mycorrhizal fungi reveals that climate variables are the primary drivers of the distribution of different types of symbiosis.

Las vacunas son la principal herramienta para prevenir la enfermedad neumocócica invasiva (ENI). El reemplazo por serotipos no vacunales es una amenaza para la efectividad de las vacunas antineumocócicas conjugadas (VCN). El objetivo principal de este estudio es valorar el impacto del SARS-CoV-2 en la epidemiología de neumococo, analizando concretamente los nuevos serotipos vacunales 22F y 33F.

Se evaluó la distribución de serotipos de la enfermedad neumocócica invasiva (ENI) por grupos de edad en España, así como el impacto de las vacunas antineumocócicas y el SARS-CoV-2.

ABSTRACTIn this article, the software and hardware control architecture for a novel high-temperature three-phase electric air heating furnace is presented. It consists of a multiple-input single-output (MISO) nonlinear plant designed to heat air at flow rates in a range between 10 and 60 Nm3/h, from ambient temperature up to 1000 °C.A divide-and-conquer (D&C) approach is applied. It consists in discretizing the air flow rates and working temperatures in intervals where the system behaviour is considered as single-input single-output (SISO) linear plant. Process identification techniques have been used to obtain empiric models for different operation ranges of the electric furnace. The controller parameters have been calculated using the Ziegler–Nichols tuning method.The resulting output air temperature control is composed of a set of 12 PI and PID controllers. The switch among controllers as a function of air flow rates and temperatures is carried out using programming logic and gain scheduling technique, respectively. The resulting multiple controller has been tested under real conditions and the results are presented and discussed.

To describe the preparation of topical endotracheal mitomycin C and the clinical outcomes of four patients with recurrent and severe laryngotracheal stenosis (LTS) treated with adjuvant topical mitomycin C.

Presentamos un caso de extracción quirúrgica de una burbuja de perfluorocarbono líquido (PFCL) subfoveal, mediante la producción de un desprendimiento retiniano macular terapéutico y aspirado de la burbuja de PFCL.

OBJECTIVE: To analyze the mechanisms involved in the characteristic hyperexpression of CD23 on peripheral blood B cells from patients with rheumatoid arthritis (RA). METHODS: Peripheral blood mononuclear cells (PBMC) were obtained from patients with active disease and activated during 18 h with an anti-CD3 monoclonal antibody in the presence or absence of blocking antibodies to CD154 or CD40. PBMC were further purified by rosetting and CD23 expression was assessed on B cells by flow cytometry after double staining (CD19/CD23). Lymphocytes were also isolated from synovial fluid (SF). CD154 expression was analyzed on PB or SF CD4+ T cells after double staining (CD4/CD154) by flow cytometry at basal conditions and after different stimuli [anti-CD3 or phorbol myristic acetate (PMA) plus ionomycin]. Co-culture experiments between SF and PB cells were performed to analyze the involvement of the CD40-CD154 interaction on CD23 expression. CD154 and CD23 expression was also analyzed on synovial membrane by immunohistochemical techniques. RESULTS: A high proportion of activated CD23 B cells was detected in patients with RA. Blocking experiments with both anti-CD40 and anti-CD154 Mab showed a significant reduction in the proportion of PB B cells expressing CD23. Following activation with anti-CD3 Mab or PMA plus ionomycin, CD154 expression was mainly induced on PB CD4+ T cells. In co-culture experiments, SF T cells were more efficient than PB T cells in inducing CD40 dependent CD23 expression on PB B cells. In addition, CD4+ T cells from synovial membrane clearly expressed CD154. CONCLUSION: Our results establish a link between CD154-CD40 pathway and CD23 expression on PB B cells from patients with RA. T cells from the synovial microenvironment were active participants in this CD23 expression, presumably in the context of cell recirculation.

The hydrogenation activity of Pt supported on activated carbon would depend on both the Pt dispersity (which can be modified by a partial carbon burn-off in air) and the impurities concentration.

The enhancement of the activity of a carbon treated with HF is due to the drastic diminution of its inorganic impurities, which produces an increase of the surface area of the carbon, a stronger Pt-C interaction and a higher Pt dispersity.

Pt−Re/Al2O3 prepared under different impregnating conditions were characterized by TPR and tested in naphtha and n-heptane reforming. Catalysts showed different Pt and Re radial distributions and reduction profiles. When both metals interact, higher dehydrocyclization and conversion are retained after a deactivation step, meanwhile, when Re is segregated from Pt the catalytic performance is negatively affected.

Pt−Sn/Al2O3, Pt/Al2O3 and Sn/Al2O3 catalysts were tested for isopropanol decomposition. Dehydration activity was related to catalysts acidity. Pt/Al2O3 and bimetallic catalysts show a similar dehydrogenation activity, however, monometallic catalysts have a deactivation rate non-observable in Pt−Sn/Al2O3.

In this Letter, a middle initial and additional affiliation have been added for author G. J. Nabuurs; two statements have been added to the Supplementary Acknowledgements; and a citation to the French National Institute has been added to the Methods; see accompanying Author Correction for further details.