Aging is characterized by loss of function of the adaptive immune system, but the underlying causes are poorly understood. To assess the molecular effects of aging on B cell development, we profiled ...gene expression and chromatin features genome-wide, including histone modifications and chromosome conformation, in bone marrow pro-B and pre-B cells from young and aged mice.
Our analysis reveals that the expression levels of most genes are generally preserved in B cell precursors isolated from aged compared with young mice. Nonetheless, age-specific expression changes are observed at numerous genes, including microRNA encoding genes. Importantly, these changes are underpinned by multi-layered alterations in chromatin structure, including chromatin accessibility, histone modifications, long-range promoter interactions, and nuclear compartmentalization. Previous work has shown that differentiation is linked to changes in promoter-regulatory element interactions. We find that aging in B cell precursors is accompanied by rewiring of such interactions. We identify transcriptional downregulation of components of the insulin-like growth factor signaling pathway, in particular downregulation of Irs1 and upregulation of Let-7 microRNA expression, as a signature of the aged phenotype. These changes in expression are associated with specific alterations in H3K27me3 occupancy, suggesting that Polycomb-mediated repression plays a role in precursor B cell aging.
Changes in chromatin and 3D genome organization play an important role in shaping the altered gene expression profile of aged precursor B cells. Components of the insulin-like growth factor signaling pathways are key targets of epigenetic regulation in aging in bone marrow B cell precursors.
The aim of this research was to determine methane and carbon dioxide emissions from a hybrid constructed wetland (CW) treating anaerobically pre-treated sewage. The CW was constituted of two ...horizontal flow (free water surface followed by a subsurface) units. A long-term study was carried out as both CW units were monitored for three campaigns in Period 1 (0.9–1.5years after start-up), and four campaigns in Period 2 (4.5–5.8years after start-up). The closed chamber method with collecting surfaces of 1810cm2 was used. For this system, variability due to position in the transverse section of CW, plant presence or absence and recommended sampling period was determined.
Overall methane emissions ranged from 96 to 966mgCH4m−2 d−1, depending on several factors as the operation time, the season of the year and the position in the system. Methane emissions increased from 267±188mgCH4m−2d−1 during the second year of operation to 543±161mgCH4m−2d−1 in the sixth year of operation. Methane emissions were related to the age of the CW and the season of the year, being high in spring and becoming lower from spring to winter. Total CO2 emissions ranged mostly from 3500 to 5800mgCO2m−2d−1 during the sixth year of operation, while nitrous oxide emissions were below the detection limit of the method.
Evolution of total methane emissions from a hybrid CWs (FWS+HSSF) in operation since June 2005. Display omitted
•Emissions increased from 267mgCH4m−2d−1 (2nd yr) to 543mgCH4m−2d−1 (6th yr).•Methane emission factor increased from 4.6% (2nd yr) to 16.9% (6th yr).•CH4 emissions correlate with wetlands age and the season (R2=0.89).•CO2 emissions ranged mostly from 3500 to 5800mgCO2m−2d−1.•Reliable CH4 emissions are obtained in a few hours but CO2 emission requires 24h.
Composting of solid fraction of swine manure is a usual practice in most farms in order to obtain a fertilizer of better quality. Due to the negative hydric balance of the composting process, ...watering the composting material is necessary, what may be carried out with liquid fraction of pig manure. In this way, substantial amounts of liquid fraction can be treated by composting, allowing the recovering the nutrients and reducing the volumes to be transported to the more distant crop fields or subjected to further treatment. Thus, the main objective of this research was to study the treatment of liquid fraction of pig manure by co-composting with solid fraction of pig manure and other solid biowaste generated in rural areas. The present research is part of a project to find an integral solution for pig manure consisting of nutrient recovery through compost production and water re-use after biological purification in constructed wetlands. In accordance with the European waste management hierarchy, sustainable and low cost cleaner technologies aiming at resource recovery must be developed as an alternative to conventional technologies applied to the treatment of pig manure. This paper presents the results of composting of liquid fraction of fresh manure, which is conceived at the same time as a pig wastewater pre-treatment, wastewater volume reduction and a nutrient recovery system. Two 30 m3 turned windrows were constituted with solid fraction of pig manure and Populus sp. wood chips as bulking material at volume ratios of 1:1 and 1:2 and watered intensely with liquid fraction whilst thermophilic temperatures were maintained. Subsequently, both windrows were divided and the new windrows each received the same quantity of a different organic waste (solid fraction of pig manure, sawdust and grape bagasse), being watered with liquid fraction for a further 30 days. Stabilised composts with a nitrogen content ranging from 1.8 to 2.0% and a carbon to nitrogen ratio from 14.0 to 18.8 were obtained. Water balances showed evaporation rates ranging from 14 to 76 L/t total solids·d and overall evaporation ratios from 1 to 2.7 m3/t total solids, referred to dry matter of solid waste. While the reduction of liquid fraction volume ranged from 58 to 88% (depending on the watering rate), mass reduction of pollutants reached approximately 90% of total Kjeldahl nitrogen, ammonium and suspended solids. In comparison with traditional composting processes of solid fraction, our results show that huge amounts of liquid fraction can be treated by co-composting with solid fraction and other solid wastes. Integrating the liquid fraction of pig manure in the composting process has improved the compost quality and has reduced the pollutant load in the remaining liquid fraction, which makes possible an advanced treatment in constructed wetlands in order to reach the necessary water quality to be recycled or even to discharge in natural water bodies. In this way, both composting and constructed wetland systems can offer an integral solution for the recovery of water and fertilizer elements contained in pig manure and diverse locally generated solid wastes. However, in spite of these benefits, more research focussing on nitrogen balances, ammonia volatilisation and greenhouse emissions will be of great interest.
Display omitted
•Liquid manure (LM) was added to composting windrows at ratios of 1.7–4.7 m3/t TS.•Evaporation rates of liquid manure ranged from 14 to 76 L t−1 TS·d−1.•Overall evaporation volumes reached 1–2.7 m3/t TS.•LM reduction from 58 to 88% vol. and pollutant reduction above 90% (TKN, NH3 and TSS).•Product: stabilized composts with 1.8–2.0% N.
The mechanism by which the eukaryotic DNA-replication machinery penetrates condensed chromatin structures to replicate the underlying DNA is poorly understood. Here we provide evidence that an ...ACF1-ISWI chromatin-remodeling complex is required for replication through heterochromatin in mammalian cells. ACF1 (ATP-utilizing chromatin assembly and remodeling factor 1) and an ISWI isoform, SNF2H (sucrose nonfermenting-2 homolog), become specifically enriched in replicating pericentromeric heterochromatin. RNAi-mediated depletion of ACF1 specifically impairs the replication of pericentromeric heterochromatin. Accordingly, depletion of ACF1 causes a delay in cell-cycle progression through the late stages of S phase. In vivo depletion of SNF2H slows the progression of DNA replication throughout S phase, indicating a functional overlap with ACF1. Decondensing the heterochromatin with 5-aza-2-deoxycytidine reverses the effects of ACF1 and SNF2H depletion. Expression of an ACF1 mutant that cannot interact with SNF2H also interferes with replication of condensed chromatin. Our data suggest that an ACF1-SNF2H complex is part of a dedicated mechanism that enables DNA replication through highly condensed regions of chromatin.
A comparative long-term study of three subsurface horizontal-flow (HF) constructed wetlands (CW) treating winery wastewater was carried out. The water depth for HF1 was 0.3 m, while the depth for HF2 ...and HF3 was 0.6 m, respectively. Hydraulic loading rate ranged from 7 to 93 mm/d, while surface loading rates fell into the following ranges: 4–85 g COD/m
2
·d, 2–49 g BOD
5
/m
2
·d and 0.5–6 g TSS/m
2
·d. The percentage of biological oxygen demand (BOD
5
) removal clearly decreased when influent concentration increased, while surface removal rate increased and reached a maximum of approximately 8 g BOD
5
/m
2
·d removed in the range of 10–20 g BOD
5
/m
2
·d fed, depending on the CW depth. HF1 showed a worse performance than the other units, appearing to be more affected by high influent concentrations. Solids accumulation on gravel media, hydraulic conductivity and gas emissions were monitored over the 2.8 years of operation.
An optical system for high resolution scanning of TGEM UV photon detection systems is introduced. The structure exploits the combination of a single Au-coated TGEM under study, and an asymmetric MWPC ...(Close Cathode Chamber) as post-amplification stage. A pulsed UV LED source with emission down to 240nm has been focused to a spot of 0.07mm on the TGEM surface, and single photo-electron charge spectra has been recorded over selected two dimensional regions. This way, the TGEM gain (order of 10–100) and TGEM photo-electron detection efficiency is clearly separated, unlike in case of continuous illumination. The surface structure connected to the TGEM photon detection is well observable, including inefficiencies in the holes and at the symmetry points between holes. The detection efficiency as well as the gas gain are fluctuating from hole to hole. The gain is constant in the hexagon around any hole, pointing to the fact that the gain depends on hole geometry, and less on the position where the electron enters. The detection probability map strongly changes with the field strength above the TGEM surface, in relation to the change of the actual surface field configuration. The results can be confronted with position-dependent simulations of TGEM electron transfer and gas multiplication.
► First demonstration of Thick GEM surface scanning with single photo-electrons. ► Resolution of 0.1mm is sufficient to identify structures connected to TGEM surface field structure. ► Gain and detection efficiency and separately measurable. ► Detection efficiency is high in a ring around the holes, and gain is constant in the hexagonal collection regions.
Muography is a novel imaging technology based on particle physics instrumentation to reveal density structure of hill-sized objects. The cosmic muon flux is attenuated while penetrating into the ...ground, thus the differential local flux correlates with the overburden density-length. Underground muography exploits the close-to-zenith flux, while main challenges became portability, low power consumption, and robustness against the out-of-the-laboratory environment. Various fields could benefit from this non-invasive imaging, eg. speleology, mining, archeology, or industry. Portable gaseous tracking detector systems have been designed, built, and successfully used in several underground locations. This paper presents the designed portable muography systems, the main requirements, and measurement campaigns for calibration, natural caves, and cultural heritage.
In this work Ag nanoparticles (AgNP) with surface-enhanced Raman scattering (SERS) activity were prepared and immobilized by laser irradiation on a water/ solid interface where the aqueous phase ...contains the Ag+ cation and the solid surface is of hydrophilic nature (glass and cellulose). The so-prepared AgNP demonstrated a high SERS effectiveness in the detection of dispersed adsorbates such as the case of the anthraquinonic dye alizarin. The size and SERS effectiveness of AgNP increases with the irradiation time, the laser power, and the cation concentration. Laser-induced AgNP can be classified into two classes attending to the morphology: spherical and planar. The latter are formed after longer irradiation times, being more active regarding the SERS efficiency. Ag photoreduction can be employed for in situ detection of the dye alizarin, but when the dye is placed on a hydrophilic substrate. Even so, this in situ SERS technique could be attractive for analytical applications involving the in situ detection of the analyzed species, such as the case of dyes in artistical objects, textiles, foods, and surface analysis in general.
The production of protons, anti-protons, neutrons, deuterons and tritons in minimum bias p+C interactions is studied using a sample of 385 734 inelastic events obtained with the NA49 detector at the ...CERN SPS at 158 GeV/c beam momentum. The data cover a phase space area ranging from 0 to 1.9 GeV/c in transverse momentum and in Feynman
x
from −0.8 to 0.95 for protons, from −0.2 to 0.3 for anti-protons and from 0.1 to 0.95 for neutrons. Existing data in the far backward hemisphere are used to extend the coverage for protons and light nuclear fragments into the region of intra-nuclear cascading. The use of corresponding data sets obtained in hadron–proton collisions with the same detector allows for the detailed analysis and model-independent separation of the three principle components of hadronization in p+C interactions, namely projectile fragmentation, target fragmentation of participant nucleons and intra-nuclear cascading.
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