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1.
PLoS One ; 19(4): e0300387, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635536

RESUMO

Although biochar application to soils has been found to increase soil quality and crop yield, the biochar dispersion extent and its impacts on native soil organic carbon (SOC) has received relatively little attention. Here, the vertical and lateral migration of fine, intermediate and coarse-sized biochar (<0.5, 0.5-1 and 1-5 mm, respectively), applied at low and high doses (1.5-2 and 3-4% w/w, respectively), was tracked using stable isotope methods, along with its impact on native SOC stocks. Biochar was homogeneously mixed into the surface layer (0-7 cm depth) of a loamy sandy Acrisol in Zambia. After 4.5 y, 38-75% of the biochar carbon (BC) was lost from the applied layer and 4-25% was detected in lower soil layers (7-30 cm). Estimating BC mineralization to be no more than 8%, 25-60% was likely transported laterally out of the experimental plots. This conclusion was supported by observations of BC in the control plot and in soils up to 2 m outside of the experimental plots. These processes were likely progressive as recovery of BC in similar plots 1 year after application was greater in both surface and lower soil layers than after 4.5 y. Fine and intermediate-sized BC displayed the greatest downward migration (25.3 and 17.9%, respectively), particularly when applied at lower doses, suggesting its movement through soil inter-particle spaces. At higher dosages, fine and intermediate-sized particles may have clogged pore, so coarse biochar displayed the greatest downward migration when biochar was applied at higher doses. In the BC treatment plot soil profiles, native SOC stocks were reduced by 2.8 to 24.5% (18.4% on average), i.e. positive priming. However, some evidence suggested that the soils may switch to negative priming over time. The dispersion of biochar in soil should be considered when evaluating biochar's agronomic benefits and environmental effects.


Assuntos
Carbono , Solo , Carvão Vegetal , Agricultura/métodos
2.
Natl Sci Rev ; 11(4): nwae007, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38495813

RESUMO

China currently has the highest acid deposition globally, yet research on its status, impacts, causes and controls is lacking. Here, we compiled data and calculated critical loads regarding acid deposition. The results showed that the abatement measures in China have achieved a sharp decline in the emissions of acidifying pollutants and a continuous recovery of precipitation pH, despite the drastic growth in the economy and energy consumption. However, the risk of ecological acidification and eutrophication showed no significant decrease. With similar emission reductions, the decline in areas at risk of acidification in China (7.0%) lags behind those in Europe (20%) or the USA (15%). This was because, unlike Europe and the USA, China's abatement strategies primarily target air quality improvement rather than mitigating ecological impacts. Given that the area with the risk of eutrophication induced by nitrogen deposition remained at 13% of the country even under the scenario of achieving the dual targets of air quality and carbon dioxide mitigation in 2035, we explored an enhanced ammonia abatement pathway. With a further 27% reduction in ammonia by 2035, China could largely eliminate the impacts of acid deposition. This research serves as a valuable reference for China's future acid deposition control and for other nations facing similar challenges.

3.
Eur Neuropsychopharmacol ; 78: 54-63, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37931511

RESUMO

Major depressive disorder (MDD) is a serious disease and a burden to patients, families and society. Rodent experiments and human studies suggest that several neuropeptide systems are involved in mood regulation. The aim of this study is two-fold: (i) to monitor, with qPCR, transcript levels of the substance P/tachykinin (TAC), NPY and CCK systems in bulk samples from control and suicide subjects, targeting five postmortem brain regions including locus coeruleus (LC); and (ii) to analyse expression of neuropeptide family transcripts in LC neurons of 'normal' postmortem brains by using laser capture microdissection with Smart-Seq2 RNA sequencing. qPCR revealed distinct regional expression patterns in male and female controls with higher levels for the TAC system in the dorsal raphe nucleus and LC, versus higher transcripts levels of the NPY and CCK systems in prefrontal cortex. In suicide patients, TAC, TAC receptors and a few NPY family transcript levels were increased mainly in prefrontal cortex and LC. The second study on 'normal' noradrenergic LC neurons revealed expression of transcripts for GAL, NPY, TAC1, CCK, and TACR1 and many other peptides (e.g. Cerebellin4 and CARTPT) and receptors (e.g. Adcyap1R1 and GPR173). These data and our previous results on suicide brains indicates that the tachykinin and galanin systems may be valid targets for developing antidepressant medicines. Moreover, the perturbation of neuropeptide systems in MDD patients, and the detection of further neuropeptide and receptor transcripts in LC, shed new light on signalling in noradrenergic LC neurons and on mechanisms possibly associated with mood disorders.


Assuntos
Transtorno Depressivo Maior , Neuropeptídeos , Feminino , Humanos , Masculino , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/metabolismo , Núcleo Dorsal da Rafe , Perfilação da Expressão Gênica , Locus Cerúleo/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Substância P/metabolismo , Colecistocinina/metabolismo
4.
Eur J Neurol ; 30(10): 3142-3148, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37392418

RESUMO

BACKGROUND AND PURPOSE: COVID-19 is associated with multiple neurological manifestations. The clinical presentation, trajectory, and treatment response for three cases of myoclonus during COVID-19 infection, with no previous neurological disease, are decsribed. METODS: Analysis of cerebrospinal fluid from the cases using indirect immunohistochemistry. RESULTS: Antibodies against rodent brain tissue, and similarities in staining patterns were observed, indicating the presence of antineuronal immunoglobulin G autoantibodies targeting astrocytes in the hippocampus. CONCLUSION: Our results demontrate cerebrospinal fluid antineuronal antibodies indicating an an autoimmune involvment in the pathogenesis in COVID-19 associated myoclonus.


Assuntos
COVID-19 , Mioclonia , Doenças do Sistema Nervoso , Humanos , Autoanticorpos , Mioclonia/etiologia , COVID-19/complicações , Encéfalo
5.
Water Res ; 242: 120241, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37392509

RESUMO

An accurate depiction of mercury (Hg) reduction is important to predict Hg biogeochemistry in both aquatic and soil systems. Although the photoreduction of Hg is well documented, reduction in the dark is poorly known and is thus the focus of this work. Black carbon (BC), an important constituent of organic matter in environments, can reduce Hg2+ in dark and oxygen-deficient conditions. Fast removal of Hg2+ in BC/Hg2+ solution was observed, with 4.99-86.88 L mg-1h-1 of the reaction rate constant, which could be ascribed to the combined actions of adsorption and reduction. Meanwhile, slow Hg reduction was obtained, compared to Hg removal, with 0.06-2.16 L mg-1h-1 of the reaction rate constant. Thus, in the initial stage, Hg2+ removal was mainly triggered by adsorption, rather than reduction. Afterward, the adsorbed Hg2+ on black carbon was converted into Hg0. Dissolved black carbon and aromatic CH on particulate black carbon were dominant triggers of Hg reduction for black carbon. During Hg reduction, the intastable intermediate, formed in the complex between aromatic CH and Hg2+, behaved as persistent free radicals, which could be detected by in situ electron paramagnetic resonance. Subsequently, the intastable intermediate was mainly converted into CO on black carbon and Hg0. Corresponding results of the present study highlight the important role of black carbon in the Hg biogeochemical cycle.

6.
J Clin Med ; 12(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36983329

RESUMO

BACKGROUND: A large proportion of people who sustain a whiplash injury will have persistent pain, disability, and participation problems. Several prognostic factors for functional recovery have been reported in the literature but these factors are often evaluated based on differing implementations in clinical practice. Additionally, physiotherapists also rely on their clinical intuition to estimate the functional prognosis of their patients, but this is seldom measured in experimental research. Furthermore, no study to date has explored the associations between clinical intuition, clinically estimated factors, and objectively measured factors for functional recovery of patients with Whiplash-Associated Disorders (WAD). AIM: The aim of this exploratory study is to evaluate associations between prognostic factors for functional recovery, based on routinely collected data in a specialized primary care physiotherapy practice in a consecutive sample of patients (n = 523) with WAD. METHODS: Three sources of prognostic factors were selected: (1) physiotherapists' synthesis of clinical intuition in terms of high-risk, inconclusive risk, or low-risk for functional recovery, (2) patient-registered factors from history taking, and (3) patient-reported prognostic factors derived from questionnaires. Prognostic factors were selected based on the literature, recommendations in Dutch clinical practice guidelines, and consensus between experts. Spearman's rank correlation coefficients were calculated to explore the associations between sources of prognostic factors, using a cutoff ≥0.25 for acceptable association. RESULTS: Associations between physiotherapists' intuitive synthesis and patient-registered variables were substantial (rs = 0.86), between patient-registered variables and patient-reported variables fair (ranging from 0.30 to 0.41) to substantial (ranging from 0.69 to 0.73), and between physiotherapists intuitive synthesis and patient-reported variables fair (ranging from 0.30 to 0.37). CONCLUSION: When estimating prognosis for functional recovery using clinical reasoning, physiotherapists should integrate patients' registered experience of their course of recovery, as well as the timeline after an accident, with their own synthesis of clinical intuition regarding prognostic factors in patients with WAD.

7.
J Environ Manage ; 337: 117721, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36966634

RESUMO

Here, we assess the effects of gypsum and local organic waste as amendments to non-weathered, filter-pressed bauxite residue (BR) to improve its properties and support plant growth. In addition, we monitored the leachate quality of the amended BR under progressive leaching that simulated precipitation conditions in Northern Brazil. Free-draining column tests consisting of BR amended with gypsum and organic waste, at 5% and 10% w/w, respectively, were leached for 8 weeks to assess the effects on the chemical composition of BR and the leachates. Adding gypsum to BR reduced the exchangeable sodium (Na) percentage (ESP) from approximately 79%-48%, whereas adding only organic waste had smaller effects on ESP (from ∼79% to âˆ¼ 70%). The mean leachate pH ranged from 8.7 to 9.4 for the gypsum, and organic waste amended BR, while this was 10.3 in the leachate of the unamended BR. The treatments had similar trends of electrical conductivity throughout the experiments and were below 2 dS/cm after 8 weeks, when ∼1.700 mm simulated precipitation had leached. Aluminium (Al), Arsenic (As), and Vanadium (V) concentrations in leachates of BR with gypsum, either alone or in combination with organic waste, were significantly lowered than in leachate of non-amended BR. By contrast, metal concentrations increased if organic waste was added to BR. We conclude that amending BR with gypsum, in combination with organic waste, significantly improves the chemical properties of the solid phase and achieved rehabilitation goals for SAR and EC of the leachates after 8 weeks of leaching. However, despite high leaching rates, rehabilitation goals for pH and ESP were not achieved with gypsum either alone or combined with organic waste.


Assuntos
Óxido de Alumínio , Poluentes do Solo , Óxido de Alumínio/química , Sulfato de Cálcio/química , Solo/química , Alumínio , Metais/química , Sódio , Poluentes do Solo/química
8.
J Environ Manage ; 334: 117511, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36801691

RESUMO

The rapid growth of energy-intensive and high-emission industries has propelled China's economy but has also led to massive levels of air pollutant emissions and ecological problems, such as acid deposition. Despite recent declines, atmospheric acid deposition in China is still severe. Long-term exposure to high levels of acid depositions has a substantial negative impact on the ecosystem. Evaluating these hazards and incorporating this issue into planning and decision-making processes is critical to achieving sustainable development goals in China. However, the long-term economic loss caused by atmospheric acid deposition and its temporal and spatial variation in China is unclear. Hence, the aim of this study was to assess the environmental cost of acid deposition in the agriculture, forestry, construction, and transportation industries from 1980 to 2019, using long-term monitoring, integrated data, and the dose-response method with localization parameters. The results showed that the estimated cumulative environmental cost of acid deposition was USD 230 billion, representing 0.27% of the gross domestic product (GDP) in China. This cost, was particularly high for building materials, followed by crops, forests, and roads. Temporally, the environmental cost and the ratio of environmental cost to GDP decreased from their peaks by 43% and 91%, respectively, because of emission controls targeting acidifying pollutants and promotion of clean energy. Spatially, the largest environmental cost occurred in developing provinces, indicating that more stringent emission reduction measures should be implemented in these regions. These findings highlight the huge environmental costs behind rapid development; however, the implementation of reasonable emission reduction measures can effectively reduce these environmental costs, providing a promising paradigm for other undeveloped and developing countries.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Ecossistema , China , Poluentes Atmosféricos/análise , Florestas , Desenvolvimento Econômico
11.
Acta Neuropathol ; 144(4): 651-676, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36040521

RESUMO

Tau pathology of the noradrenergic locus coeruleus (LC) is a hallmark of several age-related neurodegenerative disorders, including Alzheimer's disease. However, a comprehensive neuropathological examination of the LC is difficult due to its small size and rod-like shape. To investigate the LC cytoarchitecture and tau cytoskeletal pathology in relation to possible propagation patterns of disease-associated tau in an unprecedented large-scale three-dimensional view, we utilized volume immunostaining and optical clearing technology combined with light sheet fluorescence microscopy. We examined AT8+ pathological tau in the LC/pericoerulear region of 20 brains from Braak neurofibrillary tangle (NFT) stage 0-6. We demonstrate an intriguing morphological complexity and heterogeneity of AT8+ cellular structures in the LC, representing various intracellular stages of NFT maturation and their diverse transition forms. We describe novel morphologies of neuronal tau pathology such as AT8+ cells with fine filamentous somatic protrusions or with disintegrating soma. We show that gradual dendritic atrophy is the first morphological sign of the degeneration of tangle-bearing neurons, even preceding axonal lesions. Interestingly, irrespective of the Braak NFT stage, tau pathology is more advanced in the dorsal LC that preferentially projects to vulnerable forebrain regions in Alzheimer's disease, like the hippocampus or neocortical areas, compared to the ventral LC projecting to the cerebellum and medulla. Moreover, already in the precortical Braak 0 stage, 3D analysis reveals clustering tendency and dendro-dendritic close appositions of AT8+ LC neurons, AT8+ long axons of NFT-bearing cells that join the ascending dorsal noradrenergic bundle after leaving the LC, as well as AT8+ processes of NFT-bearing LC neurons that target the 4th ventricle wall. Our study suggests that the unique cytoarchitecture, comprised of a densely packed and dendritically extensively interconnected neuronal network with long projections, makes the human LC to be an ideal anatomical template for early accumulation and trans-neuronal spreading of hyperphosphorylated tau.


Assuntos
Doença de Alzheimer , Locus Cerúleo , Doença de Alzheimer/patologia , Humanos , Imageamento Tridimensional , Locus Cerúleo/patologia , Emaranhados Neurofibrilares/patologia , Proteínas tau/metabolismo
12.
Proc Natl Acad Sci U S A ; 119(33): e2123146119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35947618

RESUMO

Human prefrontal cortex (hPFC) is a complex brain region involved in cognitive and emotional processes and several psychiatric disorders. Here, we present an overview of the distribution of the peptidergic systems in 17 subregions of hPFC and three reference cortices obtained by microdissection and based on RNA sequencing and RNAscope methods integrated with published single-cell transcriptomics data. We detected expression of 60 neuropeptides and 60 neuropeptide receptors in at least one of the hPFC subregions. The results reveal that the peptidergic landscape in PFC consists of closely located and functionally different subregions with unique peptide/transmitter-related profiles. Neuropeptide-rich PFC subregions were identified, encompassing regions from anterior cingulate cortex/orbitofrontal gyrus. Furthermore, marked differences in gene expression exist between different PFC regions (>5-fold; cocaine and amphetamine-regulated transcript peptide) as well as between PFC regions and reference regions, for example, for somatostatin and several receptors. We suggest that the present approach allows definition of, still hypothetical, microcircuits exemplified by glutamatergic neurons expressing a peptide cotransmitter either as an agonist (hypocretin/orexin) or antagonist (galanin). Specific neuropeptide receptors have been identified as possible targets for neuronal afferents and, interestingly, peripheral blood-borne peptide hormones (leptin, adiponectin, gastric inhibitory peptide, glucagon-like peptides, and peptide YY). Together with other recent publications, our results support the view that neuropeptide systems may play an important role in hPFC and underpin the concept that neuropeptide signaling helps stabilize circuit connectivity and fine-tune/modulate PFC functions executed during health and disease.


Assuntos
Neuropeptídeos , Córtex Pré-Frontal , Receptores de Neuropeptídeos , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Córtex Pré-Frontal/metabolismo , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo
13.
Nat Commun ; 13(1): 3620, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35750885

RESUMO

Pigs are valuable large animal models for biomedical and genetic research, but insights into the tissue- and cell-type-specific transcriptome and heterogeneity remain limited. By leveraging single-cell RNA sequencing, we generate a multiple-organ single-cell transcriptomic map containing over 200,000 pig cells from 20 tissues/organs. We comprehensively characterize the heterogeneity of cells in tissues and identify 234 cell clusters, representing 58 major cell types. In-depth integrative analysis of endothelial cells reveals a high degree of heterogeneity. We identify several functionally distinct endothelial cell phenotypes, including an endothelial to mesenchymal transition subtype in adipose tissues. Intercellular communication analysis predicts tissue- and cell type-specific crosstalk between endothelial cells and other cell types through the VEGF, PDGF, TGF-ß, and BMP pathways. Regulon analysis of single-cell transcriptome of microglia in pig and 12 other species further identifies MEF2C as an evolutionally conserved regulon in the microglia. Our work describes the landscape of single-cell transcriptomes within diverse pig organs and identifies the heterogeneity of endothelial cells and evolutionally conserved regulon in microglia.


Assuntos
Células Endoteliais , Microglia , Animais , Microglia/metabolismo , Fenótipo , Regulon/genética , Análise de Célula Única , Suínos , Transcriptoma
14.
Sci Total Environ ; 827: 154338, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35257752

RESUMO

Soil acidification along with base cations loss degrades soil quality and is a major environmental problem, especially in agroecosystems with extensive nitrogen (N) fertilization. So far, the rates of proton (H+) production and real soil acidification (loss of base cations) remain unclear in subtropical agricultural watersheds. To assess the current status and future risk of soil acidification in subtropical red soil region of China, a two-year monitoring was conducted in a typical agricultural watershed with upland, paddy fields, and orchards where high N fertilizers are applied (320 kg N ha-1 yr-1). H+ production, neutralization and base cations losses were quantified based on the inputs (rainwater, inflow of water, and fertilizer) and outputs (outflow of water, groundwater drainage, and plant uptake) of major elements (K+, Ca2+, Na+, Mg2+, Al3+, NH4+, NO3-, SO42-, Cl-, and H+). The result showed that total H+ production in the watershed was 5152 molc ha-1 yr-1. N transformation was the most important H+ source (68%), followed by excess plant uptake of cations (25%) and H+ deposition (7%). Base cations exchange and weathering of minerals (3842 molc ha-1 yr-1) dominated H+ neutralization, followed by SO42- adsorption (1081 molc ha-1 yr-1), while H+ and Al3+ leaching amounted to 431 molc ha-1 yr-1, only. These results state clearly that despite significant soil acidification, the acidification of surface waters is minor, implying that soils have buffered substantially the net H+ addition. As a result of soil buffering, there was abundant loss of base cations, whose rate is significantly higher than the previously reported weathering rate of minerals in red soils (3842 vs 230-1080 molc ha-1 yr-1). This suggests that the pool of exchangeable base cations is being depleted in the watershed, increasing the vulnerability of the watershed, and posing a serious threat to future recovery of soils from acidification.


Assuntos
Agricultura , Solo , Cátions , Fertilizantes/análise , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Água
15.
BMC Biol ; 20(1): 25, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35073880

RESUMO

BACKGROUND: There is a need for functional genome-wide annotation of the protein-coding genes to get a deeper understanding of mammalian biology. Here, a new annotation strategy is introduced based on dimensionality reduction and density-based clustering of whole-body co-expression patterns. This strategy has been used to explore the gene expression landscape in pig, and we present a whole-body map of all protein-coding genes in all major pig tissues and organs. RESULTS: An open-access pig expression map ( www.rnaatlas.org ) is presented based on the expression of 350 samples across 98 well-defined pig tissues divided into 44 tissue groups. A new UMAP-based classification scheme is introduced, in which all protein-coding genes are stratified into tissue expression clusters based on body-wide expression profiles. The distribution and tissue specificity of all 22,342 protein-coding pig genes are presented. CONCLUSIONS: Here, we present a new genome-wide annotation strategy based on dimensionality reduction and density-based clustering. A genome-wide resource of the transcriptome map across all major tissues and organs in pig is presented, and the data is available as an open-access resource ( www.rnaatlas.org ), including a comparison to the expression of human orthologs.


Assuntos
Genoma , Genômica , Animais , Perfilação da Expressão Gênica , Mamíferos , Anotação de Sequência Molecular , Especificidade de Órgãos , Suínos/genética , Transcriptoma
16.
Environ Sci Pollut Res Int ; 29(14): 20186-20199, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34725759

RESUMO

Nitrate (NO3-) loss and enrichment in water bodies caused by fertilization are a major environmental problem in agricultural areas. However, the quantitative contribution of different NO3- sources, especially chemical fertilizers (CF) and soil organic nitrogen (SON), to NO3- runoff loss remains unclear. In this study, a systematic investigation of NO3- runoff and its sources was conducted in a subtropical agricultural watershed located in Yujiang County, Jiangxi Province, China. A semi-monthly sampling was performed at the inlet and outlet from March 2018 to February 2019. Hydrochemical and dual NO3- isotope (15 N and 18O) approaches were combined to estimate the NO3- runoff loss and quantify the contribution of different sources with a Bayesian isotope mixing model. Source apportionment by Stable Isotope Analysis in R (SIAR) suggested that NO3- in runoff was mainly derived from nitrification of ammonium (NH4+) mineralized from SON (37-52%) and manure/sewage (M&S) (25-47%), while the contribution of CF was relatively small (14-25%). The contribution of various sources showed seasonal variations, with a greater contribution of CF in the wet growing season (March to August). Compared with the inlet which contributed 37-40% to runoff NO3-, SON contributed more at the outlet (49-52%). Denitrification in the runoff was small and appeared to be confined to the dry season (September to February), with an estimated NO3- loss of 2.73 kg N ha-1. The net NO3- runoff loss of the watershed was 34.5 kg N ha-1 yr-1, accounting for 15% of the annual fertilization rate (229 kg N ha-1 yr-1). Besides M&S (22%), fertilization and remineralization of SON (CF + SON) were the main sources for the NO3- runoff loss (78%), suggesting accelerated nitrification of NH4+ from CF (24%) and SON mineralization (54%). Our study indicates that NO3- runoff loss in subtropical agricultural watersheds is dominated by nonpoint source pollution from fertilization. SON played a more important role than CF. Besides, the contribution of sewage should not be neglected. Our data suggest that a combination of more rational fertilizer N application (CF), better management of SON, and better treatment of domestic sewage could alleviate NO3- pollution in subtropical China.


Assuntos
Nitratos , Poluentes Químicos da Água , Teorema de Bayes , China , Monitoramento Ambiental , Nitratos/análise , Isótopos de Nitrogênio/análise , Poluentes Químicos da Água/análise
17.
Sci Total Environ ; 816: 151596, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-34774948

RESUMO

Nitrogen (N)-induced soil acidification has received much attention worldwide. Nitrification and soil N mineralization are two key N cycle processes that affect soil acidification. However, the seasonal dynamics of soil pH under their combined influence is unclear. We studied the effect of N fertilization on soil pH and N transformations using 15N tracing in field lysimeters with soils developed from different parent materials (Quaternary red clay, sandstone, and basalt). Maize was planted with 200 kg N ha-1 yr-115N-labeled urea addition. During 7-45 days after fertilization, proton (H+) production due to nitrification of fertilizer N, nitrate (NO3-) leaching, and plant uptake exceeded H+ consumption by base cations mobilization and leaching, resulting in a significant soil pH decline. When nitrification activity decreased (after 45 days), due to exhausted ammonium (NH4+) availability, soil pH rose again. During the fallow period, acid neutralization due to base cation mobilization, and ammonification of soil organic N (SON) offset H+ production caused by nitrification of mineralized SON, leading to a sustained rise in soil pH. After the one-year experiment, no significant soil pH decrease was observed in any of the soils. Parent material had little effect on the seasonal dynamics of soil acidification, which appeared to be controlled by fertilization, environmental factors (temperature and moisture), and plant uptake. In subtropical regions, monitoring of soil pH on an annual basis may mask the effect of N fertilization on soil acidification.


Assuntos
Nitrificação , Solo , China , Fertilização , Fertilizantes/análise , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Estações do Ano
18.
NPJ Precis Oncol ; 5(1): 97, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34799669

RESUMO

Uterine sarcomas are rare but deadly malignancies without effective treatment. Immunotherapy is a promising new approach to treat these tumors but has shown heterogeneous effects in sarcoma patients. With the goal of identifying key factors for improved patient treatment, we characterized the tumor immune landscape in 58 uterine sarcoma cases with full clinicopathological annotation. Immune cell characterization revealed the overall prevalence of FOXP3+ cells and pro-tumor M2-like macrophages. Hierarchical clustering of patients showed four tumor type-independent immune signatures, where infiltration of FOXP3+ cells and M1-like macrophages associated with favorable prognosis. High CD8+/FOXP3+ ratio in UUS and ESS correlated with poor survival, upregulation of immunosuppressive markers, extracellular matrix (ECM)-related genes and proteins, and YAP activation. This study shows that uterine sarcomas present distinct immune signatures with prognostic value, independent of tumor type, and suggests that targeting the ECM could be beneficial for future treatments.

19.
J Environ Manage ; 296: 113187, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34217940

RESUMO

On the cultivated slopes of the highlands of southwest Ethiopia, soil degradation due to water erosion is a challenge for crop production. To limit surface runoff and soil erosion, soil bunds often in combination with trenches, constructed along contour lines, are common. In addition to the interception of surface runoff, soil bunds may affect crop yield. Here, we evaluate effect of soil bunds on surface runoff and maize yield, using FAO's AquaCrop model, calibrated based on field experiments in the Bokole-Karetha watershed, in SW Ethiopia. Experiments were conducted in 2018 and 2019 on three neighboring fields, each comprising plots in triplicate without and with soil bunds. Experimental data from 2018 to 2019, which were average and above average with respect to rainfall, indicate that water availability was sufficient or even in excess for maize production. Soil bunds significantly (p < 0.05) reduced surface runoff, but maize yield did not differ significantly. In plots without soil bunds, the AquaCrop model described surface runoff satisfactorily after slight adjustment of the curve number (related to infiltration capacity) in one of the three fields. Maize yields were reproduced adequately after calibrating soil fertility and adjusting water productivity. After calibration and validation, the AquaCrop model was used to hindcast surface runoff and grain yield from 1999 to 2017, given available climatic data for the region. Hindcasts show that maize yield in the Bokole-Karetha watershed, with its relatively high rainfall, is not significantly affected by rainfall in two of the three fields. In the third field maize yield decreases slightly, but significantly (p < 0.05) with rainfall. In the short run, yield differences between plots with and without soil bunds are not significant. However, eventually high surface runoff from plots without soil bunds are expected to result in unsustainable crop production, due to significant erosion and degradation of the often nutrient-poor soils. Implementation of soil and water management techniques, combined with fertilization, are important to prevent soil degradation and nutrient stress on sloping land.


Assuntos
Conservação dos Recursos Hídricos , Solo , Conservação dos Recursos Naturais , Etiópia , Chuva , Movimentos da Água , Zea mays
20.
Sci Adv ; 7(30)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34290096

RESUMO

Hepatic nerves have a complex role in synchronizing liver metabolism. Here, we used three-dimensional (3D) immunoimaging to explore the integrity of the hepatic nervous system in experimental and human nonalcoholic fatty liver disease (NAFLD). We demonstrate parallel signs of mild degeneration and axonal sprouting of sympathetic innervations in early stages of experimental NAFLD and a collapse of sympathetic arborization in steatohepatitis. Human fatty livers display a similar pattern of sympathetic nerve degeneration, correlating with the severity of NAFLD pathology. We show that chronic sympathetic hyperexcitation is a key factor in the axonal degeneration, here genetically phenocopied in mice deficient of the Rac-1 activator Vav3. In experimental steatohepatitis, 3D imaging reveals a severe portal vein contraction, spatially correlated with the extension of the remaining nerves around the portal vein, enlightening a potential intrahepatic neuronal mechanism of portal hypertension. These fundamental alterations in liver innervation and vasculature uncover previously unidentified neuronal components in NAFLD pathomechanisms.

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