Internal or external magma oceans in the earliest protoplanets -- perspectives from nitrogen and carbon fractionation

When the extent of protoplanetary melting approached magma ocean (MO)-like conditions, alloy melts efficiently segregated from the silicates to form metallic cores. The nature of the MO of a differentiating protoplanet, i.e., internal or external MO (IMO or EMO), not only determines the abundances of life-essential volatiles like nitrogen (N) and carbon (C) in its core and mantle reservoirs but also the timing and mechanism of volatile loss. Whether the earliest formed protoplanets had IMOs or EMOs is, however, poorly understood. Here we model equilibrium N and C partitioning between alloy and silicate melts in the absence (IMO) or presence (EMO) of vapor degassed atmospheres. Bulk N and C inventories of the protoplanets during core formation are constrained for IMOs and EMOs by comparing the predicted N and C abundances in the alloy melts from both scenarios with N and C concentrations in the parent cores of magmatic iron meteorites. Our results show that in comparison to EMOs, protoplanets having IMOs satisfy N and C contents of the parent cores with substantially lower amounts of bulk N and C present in the parent body during core formation. As the required bulk N and C contents for IMOs and EMOs are in the sub-chondritic and chondritic range, respectively, N and C fractionation models alone cannot be used to distinguish the prevalence of these two end-member differentiation regimes. A comparison of N and C abundances in chondrites with their peak metamorphic temperatures suggests that protoplanetary interiors could lose a substantial portion of their N and C inventories with increasing degrees of thermal metamorphism.Comment: 19 pages, 8 figures, 1 tabl

H α fluxes and extinction distances for planetary nebulae in the IPHAS survey of the northern galactic plane

We report H α filter photometry for 197 Northern hemisphere planetary nebulae (PNe) obtained using imaging data from the IPHAS survey. H α+[N II] fluxes were measured for 46 confirmed or possible PNe discovered by the IPHAS survey and for 151 previously catalogued PNe that fell within the area of the northern Galactic Plane surveyed by IPHAS. After correcting for [N II] emission admitted by the IPHAS H α filter, the resulting H α fluxes were combined with published radio free–free fluxes and H β fluxes, in order to estimate mean optical extinctions to 143 PNe using ratios involving their integrated Balmer line fluxes and their extinction-free radio fluxes. Distances to the PNe were then estimated using three different 3D interstellar dust extinction mapping methods, including the IPHAS-based H-MEAD algorithm of Sale (2014). These methods were used to plot dust extinction versus distance relationships for the lines of sight to the PNe; the intercepts with the derived dust optical extinctions allowed distances to the PNe to be inferred. For 17 of the PNe in our sample reliable GaiaDR2 distances were available and these have been compared with the distances derived using three different extinction mapping algorithms as well as with distances from the nebular radius versus H α surface brightness relation of Frew et al. (2016). That relation and the H-MEAD extinction mapping algorithm yielded the closest agreement with the Gaia DR2 distances

Relative Bioavailability and Bioaccessibility and Speciation of Arsenic in Contaminated Soils

Background: Assessment of soil arsenic (As) bioavailability may profoundly affect the extent of remediation required at contaminated sites by improving human exposure estimates. Because small adjustments in soil As bioavailability estimates can significantly alter risk assessments and remediation goals, convenient, rapid, reliable, and inexpensive tools are needed to determine soil As bioavailability

Expression and regulation of HIF-1alpha in macrophages under inflammatory conditions; significant reduction of VEGF by CaMKII inhibitor

<p>Abstract</p> <p>Background</p> <p>Macrophages expressing the pro-angiogenic transcription factor hypoxia-inducible factor (HIF)-1alpha have been demonstrated in rheumatoid arthritis (RA) in the synovial tissue. Aim of the present study was to investigate intracellular signal transduction regulation of pro-inflammatory HIF-1 alpha expression in macrophages to identify possible new intervention strategies. We investigated the effects of CaMKII-inhibitors amongst other kinase inhibitors, on HIF-1 alpha expression and downstream production of pro-angiogenic factors in macrophages.</p> <p>Methods</p> <p>Differentiated THP-1 cells and synovial fluid (SF) macrophages were stimulated with 1 μg/ml LPS with or without pretreatment with specific inhibitors of the ERK pathway (PD98059), the PI3K pathway (LY294002), and the CaMKII pathway (KN93 and SMP-114). mRNA and protein expression of HIF-1 alpha, VEGF, MMP-9, and IL-8 was measured in cell lysates and cell supernatants.</p> <p>Results</p> <p>HIF-1 alpha protein expression in LPS-stimulated THP-1 macrophages could be blocked by ERK- and PI3K-inhibitors, but also by the CaMKII inhibitor KN93. THP-1 and SF macrophages produced high levels of VEGF, IL-8, and MMP-9, and VEGF protein production was significantly inhibited by PI3K-inhibitor, and by both CaMKII inhibitors. LPS stimulation in an hypoxic environment did not change VEGF levels, suggesting that LPS induced VEGF production in macrophages is more important than the hypoxic induction.</p> <p>Conclusions</p> <p>Expression of HIF-1 alpha and downstream effects in macrophages are regulated by ERK-, PI3K, but also by CaMKII pathways. Inhibition of HIF-1α protein expression and significant inhibition of VEGF production in macrophages was found using CaMKII inhibitors. This is an unknown but very interesting effect of the CaMKII inhibitor SMP-114, which has been in clinical trial as DMARD for the treatment of RA. This effect may contribute to the anti-arthritic effects of SMP-114.</p

Galectin-3 alters the lateral mobility and clustering of beta 1-integrin receptors

Glycoprotein receptors are influenced by myriad intermolecular interactions at the cell surface. Specific glycan structures may interact with endogenous lectins that enforce or disrupt receptor-receptor interactions. Glycoproteins bound by multivalent lectins may form extended oligomers or lattices, altering the lateral mobility of the receptor and influencing its function through endocytosis or changes in activation. In this study, we have examined the interaction of Galectin-3 (Gal-3), a human lectin, with adhesion receptors. We measured the effect of recombinant Gal-3 added exogenously on the lateral mobility of the alpha 5 beta 1 integrin on HeLa cells. Using single-particle tracking (SPT) we detected increased lateral mobility of the integrin in the presence of Gal-3, while its truncated C-terminal domain (Gal-3C) showed only minor reductions in lateral mobility. Treatment of cells with Gal-3 increased beta 1-integrin mediated migration with no apparent changes in viability. In contrast, Gal-3C decreased both cell migration and viability. Fluorescence microscopy allowed us to confirm that exogenous Gal-3 resulted in reorganization of the integrin into larger clusters. We used a proteomics analysis to confirm that cells expressed endogenous Gal-3, and found that addition of competitive oligosaccharide ligands for the lectin altered the lateral mobility of the integrin. Together, our results are consistent with a Gal-3-integrin lattice model of binding and confirm that the lateral mobility of integrins is natively regulated, in part, by galectins

Active Camera Control from Compressed Image Streams

In this paper we describe a new framework to control an active camera platform in order to improve the performance of tasks such as active stereo vision. This framework encompasses both calibrated and uncalibrated operations. We show how to control the camera system by making measurements as much as possible on compressed video streams. Coarse depth information, object segmentation, and focus and zoom control can be obtained from JPEG/MPEG streams without complete image stream decompression. When better accuracy is required, finer resolution depth maps can be reconstructed in the usual way by completely recovering the pixel information in the frames of the video stream. Our experimental results show the potential of these strategies for active vision systems. Keywords: Active vision, stereo, multimedia, compression, focus, zoom 1 Introduction It is now well-known that active camera control can greatly improve the flexibility and robustness of many computer vision tasks. Controlling t..

Glycated Haemoglobin A1c Measurement in Stored Whole Blood Sample is Reliable for Clinical Use. ( La Medición de la Hemoglobina Glicada en Muestras de Sangre Entera Almacenadas es Confiable para el uso Clínico)

Glycated haemoglobin A1c (HbA1c) gives an integrated plasma glycaemia for the previous 2–3 months and its measurement is central in the management of diabetic patients. However, in many developing countries because kits/regents or expertise for HbA1c measurement are not always available and the test must be conducted on fresh whole blood samples, HbA1c tests are not routinely performed. Thus, this study aimed to determine if the degradation products from whole blood sample storage are significant enough to compromise the diagnostic value of HbA1c measurements. Two hundred and thirty-one fresh whole blood samples with pre-determined HbA1c values were stored at between 2–8°C and using boronate affinity immunoassay technique, HbA1c values were then measured in the same whole blood samples after 20 days of storage. The results showed that there were no significant differences in the mean values of the initial HbA1c measurement and the values obtained after storage (7.5 ±2.0 vs. 7.5 ± 2.1, p >0.05) and this was irrespective of gender. Furthermore, irrespective of gender, there were significant correlations between the HbA1c values measured in fresh whole blood samples and values obtained after storage (r = 0.83, p < 0.01). Therefore, based on these findings and other previous reports, the effect of storage degradation product was not significant enough to compromise the clinical or research use of HbA1c test results from stored whole blood samples. However, we recommend that diagnostic laboratories should evaluate their HbA1c measurement techniques for HbA1c determination in stored whole blood samples. Any persistent upward or downward bias in stored whole blood samples should be reported to guide the physician in interpreting HbA1c results from stored whole blood samples from that laboratory and/or technique. (La Medición de la Hemoglobina Glicada en Muestras de Sangre Entera Almacenadas es Confiable para el uso Clínico) La hemoglobina glicada o glicosilada A1c (HbA1c) produce una glicemia plasmática integrada en los últimos 2–3 meses y su medición es fundamental para el tratamiento de pacientes diabéticos. Sin embargo, en muchos países en vías de desarrollo – debido a que no siempre hay kits/reactivos o conocimiento experto para la medición de HbA1c, y la prueba tiene que realizarse con muestras de sangre entera fresca – no se realizan tests de HbA1c de forma rutinaria. Así, este estudio apuntó a determinar si los productos de degradación del almacenamiento de la muestra de sangre entera son suficientemente significativos como para comprometer el valor del diagnóstico de las mediciones de las dimensiones de HbA1c. Doscientos treinta y una muestras de sangre entera fresca con valores HbA1c pre-determinados, fueron almacenadas entre 2–8°C y usando la técnica de inmunoensayo de afinidad al boronato, los valores de HbA1c fueron entonces medidos en las mismas muestras de sangre entera después de 20 días de almacenamiento. Los resultados mostraron que no había ninguna diferencia significativa en los valores promedios de la medición inicial de HbA1c y los valores obtenidos después del almacenamiento (7.5 ±2.0 vs. 7.5 ± 2.1, p > 0.05), independientemente del género. Además, con independencia del género, hubo correlaciones significativas entre los valores de HbA1c medidos en las coefmuestras de sangre entera fresca y los valores obtenidos después del almacenamiento (r = 0.83, p < 0.01). Por lo tanto, basado en estos hallazgos y otros informes anteriores, el efecto del producto de la degradación por almacenamiento no fue suficientemente significativo como para comprometer el empleo clínico o investigativo de los resultados de la prueba de HbA1c a partir de muestras de sangre entera almacenada. Sin embargo, recomendamos que los laboratorios de diagnóstico evalúen sus técnicas de medición para la determinación de HbA1c en las muestras de sangre entera almacenada. Cualquier tendencia persistente ascendente o descendente en las muestras de sangre entera almacenada debe ser reportada a fin de orientar al médico en la interpretación de los resultados de HbA1c de las muestras de sangre entera almacenadas por el laboratorio y/o para la técnica