Mixed-species plantations of Eucalyptus and legume trees can symbiotically fix nitrogen and potentially improve the soil quality and biomass productivity compared with a conventional Eucalyptus ...monoculture. In this study, we evaluated changes in the structure and abundance of different microbial groups and nitrogen cycle genes in mixed and pure plantations of Acacia mangium and Eucalyptus urograndis in an experimental area in southeastern Brazil. Soil samples (0–10 cm) collected in two- and three-year-old stands were submitted to chemical characterization and molecular analyses using DGGE and real time-PCR for bacteria (16S rRNA), fungi (ITS), and genes involved in nitrogen cycling (nirK, amoA, nifH). The mixed plantation did not significantly change general soil fertility or total soil C and N content compared with the Eucalyptus monoculture. However, there was a significant increase in available phosphorus and soil nitrate content in both the A. mangium and mixed-species treatments. The multivariate ordination of the DGGE profiles of bacteria, fungi and archaea groups showed distinct community structures in each treatment. Significant differences in the abundance of copies of the target genes were found for fungi, with higher values in the Eucalyptus followed by the mixed and A. mangium plantations. The analysis of nitrogen cycle genes showed no clear difference in the communities of nitrogen fixing bacteria or nitrifying archaea among treatments. The nitrification activity was dominated by archaea because it was not possible to detect the presence of bacterial nitrifiers; the denitrifier community had a distinct profile in the Eucalyptus monoculture. The abundance of archaeal amoA and nirK genes suggests that the A. mangium treatment had higher nitrification and lower denitrification than the other treatments, which would explain the higher soil nitrate levels found in pure A. mangium treatments. Our data suggest that mixed plantations of E. urograndis and A. mangium result in a distinct microbial community relative to the respective monocultures with positive effects on soil phosphorus and nitrate content, which potentially reduces the need for anthropogenic fertilization.
•We studied soil fertility and microbiology in an Acacia–Eucalyptus mixed plantation.•The monocultures and the mixed plantation increased soil C and N over time.•Acacia and mixed plantation showed higher soil nitrate and phosphorus than Eucalyptus.•Bacteria, fungi and Archaea community had structure altered by management practices.•Nitrate accumulation may resulted from nitrifiers increase and denitrifiers decrease.
Context.
Interstellar and circumstellar ices are largely composed of frozen water. Therefore, it is important to derive fundamental parameters for H
2
O ice such as absorption and scattering ...opacities, for which accurate complex refractive indexes are needed.
Aims.
The primary goal of the work presented here is to derive ice-grain opacities based on accurate H
2
O ice complex refractive indexes at low temperatures and to assess the impact this has on the derivation of water ice column densities and porosity in space.
Methods.
We used the
optool
code to derive ice-grain scattering and absorption opacity values based on new and previously reported mid-infrared (mid-IR) complex refractive index measurements of H
2
O ice, primarily in its amorphous form, but not exclusively. Next, we used those opacities in the
RADMC-3D
code to run a radiative transfer simulation of a protostellar envelope containing H
2
O ice, which was then used to calculate water ice column densities.
Results.
We found that the real refractive index in the mid-IR of H
2
O ice at 30 K is ~14% lower than previously reported in the literature. This has a direct impact on the ice column densities derived from the simulations of embedded protostars. Additionally, we found that ice porosity plays a significant role in the opacity of icy grains and that the H
2
O libration mode can be used as a diagnostic tool to constrain the porosity level. Finally, the refractive indexes presented here allowed us to estimate a grain size detection limit of 18 μm based on the 3 μm band, whereas the 6 μm band allowed us to trace grain sizes larger than 20 μm.
Conclusions.
Based on radiative transfer simulations using new mid-IR refractive indexes, we conclude that H
2
O ice leads to more absorption of infrared light than previously estimated. This implies that the 3 and 6 μm bands remain detectable in icy grains with sizes larger than 10 μm. Finally, we also propose that the H
2
O ice libration band can be used as a diagnostic tool to constrain the porosity level of the interstellar ice, in addition to the OH dangling bond, which is now routinely used for this purpose.
Nitrogen-bearing complex organic molecules have been commonly detected in the gas phase but not yet in interstellar ices. This has led to the long-standing question of whether these molecules form in ...the gas phase or in ices. The James Webb Space Telescope (JWST) offers the sensitivity, spectral resolution, and wavelength coverage needed to detect them in ices and investigate whether their abundance ratios are similar in gas and ice. We report the first tentative detection of CH3CN, C2H5CN and the simple molecule, N2O, based on the CN-stretch band in interstellar ices toward three (HOPS 153, HOPS 370, and IRAS 20126+4104) out of the five protostellar systems observed as part of the Investigating Protostellar Accretion (IPA) GO program with JWST-NIRSpec. We also provide upper limits for the two other sources with smaller luminosities in the sample. We detect OCN− in the ices of all sources with typical CH3CN/OCN− ratios of around 1. Ice and gas column density ratios of the nitrogen-bearing species with respect to each other are better matched than those with respect to methanol, which are a factor of ~5 larger in the ices than the gas. We attribute the elevated ice column densities with respect to methanol to the difference in snowline locations of nitrogen-bearing molecules and of methanol, biasing the gas-phase observations toward fewer nitrogen-bearing molecules. Moreover, we find tentative evidence of the enhancement of OCN−, CH3CN, and C2H5CN in warmer ices; although, the formation of these molecules likely starts along with methanol in the cold prestellar phase. Future surveys combining NIRSpec and MIRI, and additional laboratory spectroscopic measurements of C2H5CN ice, are necessary for robust detection and conclusions on the formation history of complex cyanides.
ABSTRACT
The processing of H2O:CO2:CH4 (10:1:1) and H2O:CO2:CH4:NH3 (10:1:1:1) ices at 72 K by oxygen ions was studied in an attempt to simulate the physicochemical effects induced by energetic ions ...on the surface of Enceladus (or similar cold surfaces in the outer Solar System). The experiments were carried out at the Grand Accélérateur National d’Ions Lourds (GANIL) in Caen/France. The samples were irradiated with 15.7-MeV O5+ at the IRRadiation SUD (IRRSUD) beamline and with 108-keV O6+ at the Accélérateurs pour les Recherches avec les Ions de Basses Energies (ARIBE) beamline. The frozen samples were monitored by Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy (4000–650 cm−1, 2.5–15.4 μm, at 1 cm−1 resolution). The identified molecular species formed during irradiation were CO, OCN−, CH3OH, HCN, CN−, H2CO3, HNCO, HCO and CO3. The effective formation cross-sections for the synthesis of new species and the effective molecular destruction cross-sections of the parent species in the experiments with MeV ions were found to be of the order of 10−14–10−13 cm2. For the keV ion experiments, these values were of the order of 10−16–10−15 cm2. The fluence at which the sample reaches chemical equilibrium and the molecular abundances in this region (equilibrium branching ratios) were estimated. These experiments suggest that the chemical inventory on the surface of Enceladus can be influenced by the incidence of charged particles on to the moon’s surface.
Pulmonary arterial hypertension (PAH) is a severe disease with high morbidity and mortality. Current therapies are mainly focused on vasodilative agents to improve prognosis. However, recent ...literature has shown the important interaction between immune cells and stromal vascular cells in the pathogenic modifications of the pulmonary vasculature. The immunological pathogenesis of PAH is known as a complex interplay between immune cells and vascular stromal cells, via direct contacts and/or their production of extra-cellular/diffusible factors such as cytokines, chemokines, and growth factors. These include, the B-cell-mast-cell axis, endothelium mediated fibroblast activation and subsequent M2 macrophage polarization, anti-endothelial cell antibodies and the versatile role of IL-6 on vascular cells. This review aims to outline the major pathophysiological changes in vascular cells caused by immunological mechanisms, leading to vascular remodeling, increased pulmonary vascular resistance and eventually PAH. Considering the underlying immunological mechanisms, these mechanisms may be key to halt progression of disease.
Systemic sclerosis (SSc) patients face an elevated risk of cardiovascular disease (CVD), even when classic cardiovascular risk factors are considered. Plasma dephosphorylated-uncarboxylated Matrix ...Gla-protein (dp-ucMGP), an inactive form of MGP, is associated with increased CVD risk. Smooth muscle cells, implicated in SSc's development, are the primary dp-ucMGP producers. This study assessed dp-ucMGP levels and initial CVD events in early-diagnosed SSc patients, investigating its potential as a CVD and all-cause mortality predictor over time.
In a cohort of 87 SSc patients (excluding those with pre-existing CVD or on dialysis), baseline dp-ucMGP levels were measured, along with cardiovascular risk factors. Validation involved assessing dp-ucMGP in a subset of treatment-naive SSc patients.
A significantly elevated median dp-ucMGP level of 634 pmol/L (IQR 301) compared with healthy controls (dp-ucMGP < 393 pmol/L;
< 0.001) was observed. Validation in a treatment-naive SSc patient subset yielded similar results (median 589 pmol/L; IQR 370). During a median 10.5-year follow-up among 78 SSc patients, 33.3% experienced their first CVD event, independent of traditional risk factors. Elevated dp-ucMGP levels (>634 pmol/L) correlated with a higher risk of CVD and/or death (log-rank test:
< 0.01).
In summary, dp-ucMGP emerges as a novel biomarker in SSc patients, with elevated levels indicating an increased risk of CVD and/or mortality in this population.
The Last Interglacial (c. 128,000 to 115,000 years ago) was the last time when global temperatures may have been higher than those of the Holocene, but little is known about vegetation change or ...paleoclimate during that period in Central America. A new fossil pollen record from the lowland setting of El Valle, Panama, spanned the period from 137,000 to 98,000 years ago. We used multivariate analysis of modern and fossil pollen samples to provide the first regional quantification of Last Interglacial temperature and precipitation change and found mean annual temperatures were c. 1–2 °C warmer than modern, while precipitation was mostly similar to modern. The montane genus Quercus was intermittently present throughout the interglacial period, leading to the inference that this dispersal-limited taxon was surviving in microrefugia. Both charcoal and the early successional genus Cecropia were noticeably rare in the last interglacial compared with the Holocene. The modern absence of Quercus from Central Panama does not appear to be the product of interglacial warming, but rather a result of dry conditions in the late Holocene and human activity. It is suggested that humans greatly increased fire frequency, thereby favoring Cecropia and eliminating Quercus from the lower portion of its elevational range.
•The last interglacial in Panama was between 1 and 2 °C warmer than modern and contained both wet and dry oscillations.•Quercus (oaks) survived in microrefugia below their modern limit during the last interglacial in Panama•Quercus were important components of lower-montane forests in Panama prior to human actions.•Mid-Holocene forest clearance and burning caused a loss of Quercus from their lower range in Panama.
Context.
The increasing sensitivity and resolution of ground-based telescopes have enabled the detection of gas-phase complex organic molecules (COMs) across a variety of environments. Many of the ...detected species are expected to form on the icy surface of interstellar grains and transfer later into the gas phase. Therefore, icy material is regarded as a primordial source of complex molecules in the interstellar medium. Upcoming
James Webb
Space Telescope (JWST) observations of interstellar ices in star-forming regions will reveal infrared (IR) features of frozen molecules with unprecedented resolution and sensitivity. To identify COM features in the JWST data, laboratory IR spectra of ices for conditions that simulate interstellar environments are needed.
Aims.
This work provides laboratory mid-IR spectra of methyl cyanide (CH
3
CN, also known as acetonitrile) ice in its pure form and mixed with known interstellar molecules at cryogenic temperatures. The spectroscopic data presented in this work will support the interpretation of JWST ice observations and are made available to the community through the Leiden Ice Database for Astrochemistry (LIDA).
Methods.
Fourier transform IR spectroscopy is used to record the mid-IR spectra (500–4000 cm
−1
/20–2.5 µm, with a resolution of 1 cm
−1
) of methyl cyanide (acetonitrile, CH
3
CN) mixed with H
2
O, CO, CO
2
, CH
4
, NH
3
, H
2
O:CO
2
, and H
2
O:CH
4
:NH
3
, at temperatures ranging from 15 to 150 K. The refractive index (at 632.8 nm) of pure amorphous CH
3
CN ice at 15 K and the band strength of selected IR transitions are also measured.
Results.
We present a variety of reference mid-IR spectra of frozen CH
3
CN that can be compared to astronomical ice observations. The peak position and full width at half maximum (FWHM) of six absorption bands of frozen methyl cyanide in its pure form and mixed ices, at temperatures between 15–150 K, are characterized. These bands are the following: the CH
3
symmetric stretching at 2940.9 cm
−1
(3.400 µm), the CN stretching at 2252.2 cm
−1
(4.440 µm), a peak resulting from a combination of different vibrational modes at 1448.3 cm
−1
(6.905 µm), the CH
3
antisymmetric deformation at 1410 cm
−1
(7.092 µm), the CH
3
symmetric deformation at 1374.5 cm
−1
(7.275 um), and the CH
3
rock vibration at 1041.6 cm
−1
(9.600 um). Additionally, the apparent band strength of these vibrational modes in mixed ices is derived. The laboratory spectra of CH
3
CN are compared to observations of interstellar ices toward W33A and three low-mass Young Stellar Objects (YSO). Since an unambiguous identification of solid methyl cyanide toward these objects is not possible, upper limits for the CH
3
CN column density are determined as ≤2.4 × 10
17
molecules cm
−2
for W33A and 5.2 × 10
16
, 1.9 × 10
17
, and 3.8 × 10
16
molecules cm
−2
for EC92, IRAS 03235, and L1455 IRS3, respectively. With respect to solid H
2
O, these values correspond to relative abundances of 1.9, 3.1, 1.3, and 4.1%, for W33A, EC92, IRAS 03235, and L1455 IRS3, respectively.
Recombinant virus vectors represent a promising strategy for vaccine research. Among available viral vectors, members of the
Poxviridae
family—especially the modified Vaccinia virus Ankara ...(MVA)—stand out as immunogenic and safe vaccine platforms. Because MVA usually does not produce plaques in cell culture, visible selection markers such as the green fluorescent protein (GFP) are frequently incorporated into the constructions in order to facilitate the recognition of recombinants. However, these genetic markers have to be removed before any clinical trial. Here, we evaluated the acute responses generated in mice immunized with a MVA vector in which the GFP marker was not removed. We observed no differences in neutrophil, monocyte, or total leucocyte recruitment among animals inoculated with MVA or MVA-GFP. Likewise, there were no differences in neutrophil activation between mice groups. Hepatic functions were not altered in either MVA or MVA-GFP-inoculated mice, and we observed no histopathological alterations in different tissues from virus-inoculated animals. In conclusion, the presence of GFP is innocuous to immunized animals and do not alter acute physiopathological responses to the MVA vector. We suggest that keeping the GFP marker may be a good strategy for vaccine development, production, and evaluation.
This Policy Review presents the International Myeloma Working Group's clinical practice recommendations for the treatment of relapsed and refractory multiple myeloma. Based on the results of phase 2 ...and phase 3 trials, these recommendations are proposed for the treatment of patients with relapsed and refractory disease who have received one previous line of therapy, and for patients with relapsed and refractory multiple myeloma who have received two or more previous lines of therapy. These recommendations integrate the issue of drug access in both low-income and middle-income countries and in high-income countries to help guide real-world practice and thus improve patient outcomes.
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