129 research outputs found

    Ideotyping integrated aquaculture systems to balance soil nutrients.

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    Due to growing land scarcity and lack of nutrient inputs, African farmers switched from shifting cultivation to continuous cropping and extended crop area by bringing fragile lands such as river banks and hill slopes into production. This accelerated soil fertility decline caused by erosion, harvesting and insufficient nutrient replenishment. We explored the feasibility to reduce nutrient depletion by increasing nutrient utilization efficiencies, while diversifying and increasing food production through the development of integrated aquaculture – agriculture (IAA). Considering the climatic conditions prevailing in Kenyan highlands, aquaculture production scenarios were ideotyped per agro-ecological zone. These aquaculture production scenarios were integrated into existing NUTrient MONitoring (NUTMON) farm surveydata for the area. The nutrient balances and flows of the resulting IAA-systems were compared to present land use.The effects of IAA development on nutrient depletion and total food production were evaluated. With the development of IAA systems, nutrient depletion rates dropped by 23–35%, agricultural production increased by 2–26% and overall farm food production increased by 22–70%. The study demonstrates that from a bio-physical point of view, the development of IAA-systems in Africa is technically possible and could raise soil fertility and total farm production. Further studies that evaluate the economic feasibility and impacts on the livelihood of farming households are recommended

    Bayesian Methods for Longitudinal Trending in Probabilities of Collision

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    Satellites have become an integral part of modern life, supporting phone communication, television and radio broadcasting, internet access, and military activities. Indeed, it is difficult to imagine modern society without many of these technologies, especially in an age when the world is increasingly interconnected via long-distance communications. As of 2013, there were over one thousand operational satellites in orbit about Earth. About half of these active satellites are in Low-Earth Orbit (LEO, meaning an orbital period less than 225 minutes), which is where the International Space Station (ISS) conducts operations, along with other commercial missions such as earth observation and satellite telephone communications. An increasing amount of attention is being placed on protecting satellites in LEO, as the frequency of object launches and satellite fragmentation events has contributed to the proliferation of space debris, resulting in increased congestion

    Effective targeting of DC-sign by α-fucosylamide functionalized gold nanoparticles

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    Dendritic Cells (DCs), the most potent antigenpresenting cells, play a critical role in the detection of invading pathogens, which are recognized also by multiple carbohydrate-specific receptors. Among them, DC-SIGN is one of the best characterized, with high-mannose and Lewis-type glycan specificity. In this study, we present a potent DC-SIGN targeting device developed using gold nanoparticles functionalized with \u3b1-fucosyl-\u3b2-alanyl amide. The nanoparticles bound to cellular DC-SIGN and induced internalization as effectively as similar particles coated with comparable amounts of LewisX oligosaccharide. They were found to be neutral toward dendritic cell maturation and IL-10 production, thus envisaging a possible use as targeted imaging tools and antigen delivery devices

    Peak Pc Prediction in Conjunction Analysis: Conjunction Assessment Risk Analysis

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    Satellite conjunction risk typically evaluated through the probability of collision (Pc). Considers both conjunction geometry and uncertainties in both state estimates. Conjunction events initially discovered through Joint Space Operations Center (JSpOC) screenings, usually seven days before Time of Closest Approach (TCA). However, JSpOC continues to track objects and issue conjunction updates. Changes in state estimate and reduced propagation time cause Pc to change as event develops. These changes a combination of potentially predictable development and unpredictable changes in state estimate covariance. Operationally useful datum: the peak Pc. If it can reasonably be inferred that the peak Pc value has passed, then risk assessment can be conducted against this peak value. If this value is below remediation level, then event intensity can be relaxed. Can the peak Pc location be reasonably predicted

    Adaptable antigen matrix platforms for peptide vaccination strategies and T cell-mediated anti-tumor immunity

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    Injection of antigenic peptides has been widely used as a vaccine strategy to boost T cell immunity. However, the poor immunogenicity of single peptides can potentially be strengthened through modification of the tertiary structure and the selection of the accompanying adjuvant. Here, we generated antigenic peptides into non-linear trimers by solid phase peptide synthesis, thereby enhancing antigen presentation by dendritic cells to CD8+ T cells in vitro and in vivo. CD8+ T cells from mice vaccinated with trimers showed an KLRG1+ effector phenotype and were able to recognize and kill antigen-expressing tumor cells ex vivo. Importantly, trimers outperformed synthetic long peptide in terms of T cell response even when equal number of epitopes were used for immunization. To improve the synthesis of trimers containing difficult peptide sequences, we developed a novel small molecule that functions as conjugation platform for synthetic long peptides. This platform, termed Antigen MAtriX (AMAX) improved yield, purity and solubility of trimers over conventional solid phase synthesis strategies. AMAX outperformed synthetic long peptides in terms of both CD8+ and CD4+ T cell responses and allowed functionalization with DC-SIGN-binding carbohydrates for in vivo dendritic cell targeting strategies, boosting T cell responses even further. Moreover, we show that ag

    Distinct antigen uptake receptors route to the same storage compartments for cross-presentation in dendritic cells

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    An exclusive feature of dendritic cells (DCs) is their capacity to present exogenous antigens by MHC class I molecules, called cross-presentation. Here, we show that protein antigen can be conserved in mature murine DCs for several days in a lysosome-like storage compartment, distinct from MHC class II and early endosomal compartments, as an internal source for the supply of MHC class I ligands. Using two different uptake routes via Fc gamma receptors and C-type lectin receptors, we could show that antigens were routed towards the same endolysosomal compartments after 48 h. The antigen-containing compartments lacked co-expression of molecules involved in MHC class I processing and presentation including TAP and proteasome subunits as shown by single-cell imaging flow cytometry. Moreover, we observed the absence of cathepsin S but selective co-localization of active cathepsin X with protein antigen in the storage compartments. This indicates cathepsin S-independent antigen degradation and a novel but yet undefined role for cathepsin X in antigen processing and cross-presentation by DCs. In summary, our data suggest that these antigen-containing compartments in DCs can conserve protein antigens from different uptake routes and contribute to long-lasting antigen cross-presentation.Microscopic imaging and technolog

    Validación de la versión en español de la escala de evaluación del trastorno por déficit de atención e hiperactividad (ADHD-RS-IV.es) en una muestra española

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    Objetivos El objetivo de este estudio es validar la versión en castellano del ADHD-RS-IV (ADHD-RS-IV.es) en una muestra española. Métodos A partir de una muestra total de 652 niños y adolescentes (rango edad: 6-17 años; media [DE] = 11,14 [3,27] años), se incluyó a 518 pacientes con TDAH (criterios DSM-IV-TR) y a 134 controles sanos. Para la evaluación de la estructura factorial, la validez y la fiabilidad de la escala se realizó un análisis factorial confirmatorio (CFA) mediante structural equation modeling en una matriz de correlaciones policóricas, y usando el método de máxima verosimilitud para la estimación. Se calcularon la validez discriminante y su valor predictivo mediante curvas receiver operating characteristics. Resultados La escala en castellano mostró una consistencia interna elevada, tanto para la escala total como para sus subescalas. El coeficiente alfa de Cronbach era 0,94 para la escala total y ≥ 0,90 para las subescalas. Los valores alfa ordinales eran 0,95 para la escala total y ≥ 0,90 para las subescalas. El análisis CFA mostró un modelo de 2 factores (inatención e hiperactividad/impulsividad) intercorrelacionados. La escala ofrece buen poder discriminante (AUC = 0,97). Conclusiones La versión española del ADHD-RS-IV (ADHD-RS-IV.es) mostró una estructura bifactorial consistente con los modelos del DSM-IV-TR y DSM-5, y con el modelo propuesto por el autor de la escala original. Además, posee un alto poder discriminante, lo que lo convierte en un instrumento válido y fiable para medir la presencia y severidad de síntomas de TDAH en la población española.Objectives The purpose of this study is to validate a Spanish-language version of the 18-item ADHD Rating Scale-IV (ADHD-RS-IV.es) in a Spanish sample. Methods From a total sample of 652 children and adolescents aged 6 to 17 years (mean age was 11.14 ± 3.27), we included 518 who met the DSM-IV-TR criteria for ADHD and 134 healthy controls. To evaluate the factorial structure, validity, and reliability of the scale, we performed a confirmatory factor analysis (CFA) using structural equation modelling on a polychoric correlation matrix and maximum likelihood estimation. The scale's discriminant validity and predictive value were estimated using ROC (receiver operating characteristics) curve analysis. Results Both the full scale and the subscales of the Spanish-language version of the ADHD-RS-IV showed good internal consistency. Cronbach's alpha was 0.94 for the full scale and ≥ 0.90 for the subscales, and ordinal alpha was 0.95 and ≥ 0.90, respectively. CFA showed that a two-factor model (inattention and hyperactivity/impulsivity) provided the best fit for the data. ADHD-RS-IV.es offered good discriminant ability to distinguish between patients with ADHD and controls (AUC = 0.97). Conclusions The two-factor structure of the Spanish-language version of the ADHD-RS-IV (ADHD-RS-IV.es) is consistent with those of the DSM-IV-TR and DSM-5 as well as with the model proposed by the author of the original scale. Furthermore, it has good discriminant ability. ADHD-RS-IV.es is therefore a valid and reliable tool for determining presence and severity of ADHD symptoms in the Spanish population

    Implante hematopoyético de una serie de pacientes movilizados con Plerixafor. Estudio retrospectivo multicéntrico

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    Poster [PC-256] Introducción: Plerixafor (PLX) es un inhibidor del receptor CXCR4 de probada eficacia en la recolección de PHSP para autotrasplante hematopoyético (TASPE) en pacientes malos movilizadores. Los estudios llevados a cabo hasta la fecha se han centrado mayoritariamente en aspectos referentes a la cinética de movilización (Mx) y rendimiento. El objetivo de nuestro estudio es recoger una amplia experiencia multicéntrica sobre el injerto hematopoyético a corto y medio plazo de pacientes que habían sido movilizados con PLX. Paciente: s y Métodos: Estudiamos retrospectivamente todos los pacientes que recibieron PLX como parte del esquema de movilización de PHSP para TASPE durante los años 2008-18 en siete hospitales de la zona norte; las enfermedades de base fueron: 94 linfomas no Hogdkin, 14 con enfermedad de Hogdkin, 78 mieloma múltiple y 4 con otros diagnósticos. 108 pacientes eran varones (56%) y 82 mujeres (44%). Su edad mediana era 59 años (4-73). Su peso y su altura oscilaron entre 15-134 kg y 106-188 cm, respectivamente. La mediana de líneas de tratamiento de nuestra serie fue de 2 (1-5); veintiún pacientes habían recibido radioterapia extensa y 15 pacientes uno o varios TASPEs previos. El número de intentos de Mx previos osciló entre 0 y 4 (mediana: 1). La pauta de G-CSF empleada fue de 5-10 mcg/kg/12 h durante 1-14 días (mediana: 6 días) y la dosis de PLX fue la recomendada en ficha técnica (0.24mcg/Kg/24horas). En 36 casos (18, 95%) la movilización se realizó en la fase de recuperación tras un ciclo de la quimioterapia de tratamiento. Tabla 1. Características de la serie y empleo de PLX. Resultados: se realizaron un total de 159 TASPEs. El estatus de la hemopatía en el momento del trasplante era remisión completa en el 50% de los casos. En cuanto a los resultados de movilización y colecta, la mediana de sesiones de aféresis requeridas fue de 2, rango (0-5) y la cifra de células CD34+ recolectada fue de 2, 79 (x 106/kg) con un rango entre 0 y 30, 3. Tabla 2. Datos de implante a corto y medio plazo Conclusiones: 1) el empleo de Plerixafor permitió realizar el TASPE en un alto porcentaje de pacientes malos movilizadores; 2) la calidad del injerto a corto y medio plazo de los pacientes autotrasplantados movilizados con PLX fue óptimo en la gran mayoría de los casos; 3) en nuestro conocimiento, esta serie multicéntrica es una de las mayores comunicadas enfocada en la calidad del implante a corto y medio plazo de pacientes malos movilizadores sometidos a TASPE
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