Predicting catchment stormflow responses after tropical deforestation remains difficult. We used 5‐min rainfall and storm runoff data for 30 events to calibrate the Green–Ampt (GA) and the Spatially ...Variable Infiltration (SVI) models and predict runoff responses for a small, degraded grassland catchment on Leyte Island (the Philippines), where infiltration‐excess overland flow (IOF) is considered the dominant runoff process. SVI replicated individual stormflow hydrographs better than GA, particularly for events with small runoff responses or multiple peaks. Calibrated parameter values of the SVI model (i.e., spatially averaged maximum infiltration capacity, Im and initial ion, F0) varied markedly between events, but were statistically significant and negatively correlated with (mid‐slope) soil moisture content at 10 cm (SWC10)—as did the “catchment‐wide effective” hydraulic conductivity (Ke) of the GA model. Using SWC10‐based estimates of F0 and Im in SVI yielded satisfactory to good simulations for 11 out of 17 events with runoff coefficients ≥15%, but failed to reproduce the hydrographs for events with very small runoff amounts (0.25–1 mm) and low runoff coefficients (3%–6%). The median field‐measured near‐surface Ksat (2 mm hr−1) was distinctly lower than the median Im (32 mm hr−1) and, to a lesser extent, Ke (∼8 mm hr−1), suggesting an underestimation of the spatially averaged Ksat by the field measurements. Application of SVI is expected to give the most realistic results for situations where IOF is dominant, that is, where surface conditions are degraded and rainfall intensities high.
Plain Language Summary
It is important to be able to predict the streamflow volume and peak flow rate during intense rainfall events. We used rainfall and streamflow data for a small, degraded tropical grassland catchment on Leyte Island (the Philippines) to calibrate two rainfall infiltration models of comparable complexity: the Green–Ampt model (GA), that describes a decrease in infiltration capacity with time, and the Spatially Variable Infiltration (SVI) model for which the infiltration capacity is a function of the rainfall intensity. SVI generally performed better than GA in simulating observed streamflow responses to rainfall, especially for events with multiple rainfall peaks. Values for the two main parameters of SVI (the amount of rainfall required to initiate stormflow, and the maximum infiltration capacity of the soil) were related to the amount of moisture in the top 10 cm of the soil prior to the rainfall event. Using the measured topsoil moisture contents for 26 rainfall events to estimate the SVI parameter values and predict the stormflow response from the measured rainfall intensity produced satisfactory to good results for most of the larger events. However, it failed to reproduce the stormflow patterns for six events with mostly small to very small runoff responses.
Key Points
The Spatially Variable Infiltration (SVI) model outperformed the Green–Ampt model, especially when simulating multi‐peaked storm hydrographs
SVI‐model parameter values correlated negatively with antecedent topsoil moisture content
Model‐derived catchment‐scale infiltration capacities were higher than field‐measured Ksat, regardless of the model or field method used
Background
Phenotypic characterization of immune cells in the bone marrow (BM) of patients with acute myeloid leukemia (AML) is lacking.
Methods
T‐cell infiltration was quantified on BM biopsies from ...13 patients with AML, and flow cytometry was performed on BM aspirates (BMAs) from 107 patients with AML who received treatment at The University of Texas MD Anderson Cancer Center. The authors evaluated the expression of inhibitory receptors (programmed cell death protein 1 PD1, cytotoxic T‐lymphocyte antigen 4 CTLA4, lymphocyte‐activation gene 3 LAG3, T‐cell immunoglobulin and mucin‐domain containing‐3 TIM3) and stimulatory receptors (glucocorticoid‐induced tumor necrosis factor receptor‐related protein GITR, OX40, 41BB a type 2 transmembrane glycoprotein receptor, inducible T‐cell costimulatory ICOS) on T‐cell subsets and the expression of their ligands (41BBL, B7‐1, B7‐2, ICOSL, PD‐L1, PD‐L2, and OX40L) on AML blasts. Expression of these markers was correlated with patient age, karyotype, baseline next‐generation sequencing for 28 myeloid‐associated genes (including P53), and DNA methylation proteins (DNA methyltransferase 3α, isocitrate dehydrogenase 1IDH1, IDH2, Tet methylcytosine dioxygenase 2 TET2, and Fms‐related tyrosine kinase 3 FLT3).
Results
On histochemistry evaluation, the T‐cell population in BM appeared to be preserved in patients who had AML compared with healthy donors. The proportion of T‐regulatory cells (Tregs) in BMAs was higher in patients with AML than in healthy donors. PD1‐positive/OX40‐positive T cells were more frequent in AML BMAs, and a higher frequency of PD1‐positive/cluster of differentiation 8 (CD8)‐positive T cells coexpressed TIM3 or LAG3. PD1‐positive/CD8‐positive T cells were more frequent in BMAs from patients who had multiply relapsed AML than in BMAs from those who had first relapsed or newly diagnosed AML. Blasts in BMAs from patients who had TP53‐mutated AML were more frequently positive for PD‐L1.
Conclusions
The preserved T‐cell population, the increased frequency of regulatory T cells, and the expression of targetable immune receptors in AML BMAs suggest a role for T‐cell–harnessing therapies in AML.
T‐cell subsets are preserved in the bone marrow of patients with acute myeloid leukemia. The expression of targetable immune checkpoints by T cells suggests that therapies harnessing T cells may benefit these patients.
Identifying agricultural practices that enhance water cycling is critical, particularly with increased rainfall variability and greater risks of droughts and floods. Soil infiltration rates offer ...useful insights to water cycling in farming systems because they affect both yields (through soil water availability) and other ecosystem outcomes (such as pollution and flooding from runoff). For example, conventional agricultural practices that leave soils bare and vulnerable to degradation are believed to limit the capacity of soils to quickly absorb and retain water needed for crop growth. Further, it is widely assumed that farming methods such as no-till and cover crops can improve infiltration rates. Despite interest in the impacts of agricultural practices on infiltration rates, this effect has not been systematically quantified across a range of practices. To evaluate how conventional practices affect infiltration rates relative to select alternative practices (no-till, cover crops, crop rotation, introducing perennials, crop and livestock systems), we performed a meta-analysis that included 89 studies with field trials comparing at least one such alternative practice to conventional management. We found that introducing perennials (grasses, agroforestry, managed forestry) or cover crops led to the largest increases in infiltration rates (mean responses of 59.2 ± 20.9% and 34.8 ± 7.7%, respectively). Also, although the overall effect of no-till was non-significant (5.7 ± 9.7%), the practice led to increases in wetter climates and when combined with residue retention. The effect of crop rotation on infiltration rate was non-significant (18.5 ± 13.2%), and studies evaluating impacts of grazing on croplands indicated that this practice reduced infiltration rates (-21.3 ± 14.9%). Findings suggest that practices promoting ground cover and continuous roots, both of which improve soil structure, were most effective at increasing infiltration rates.
In this paper, we present and analyze a novel global database of
soil infiltration measurements, the Soil Water Infiltration Global (SWIG)
database. In total, 5023 infiltration curves were collected ...across all
continents in the SWIG database. These data were either provided and quality
checked by the scientists who performed the experiments or they were
digitized from published articles. Data from 54 different countries were
included in the database with major contributions from Iran, China, and the USA.
In addition to its extensive geographical coverage, the collected
infiltration curves cover research from 1976 to late 2017. Basic information
on measurement location and method, soil properties, and land use was
gathered along with the infiltration data, making the database valuable for
the development of pedotransfer functions (PTFs) for estimating soil hydraulic
properties, for the evaluation of infiltration measurement methods, and for
developing and validating infiltration models. Soil textural information
(clay, silt, and sand content) is available for 3842 out of 5023 infiltration
measurements (∼ 76%) covering nearly all soil USDA textural classes
except for the sandy clay and silt classes. Information on land use is
available for 76 % of the experimental sites with agricultural land use as
the dominant type (∼ 40%). We are convinced that the SWIG database
will allow for a better parameterization of the infiltration process in land
surface models and for testing infiltration models. All collected data and
related soil characteristics are provided online in
*.xlsx and *.csv formats for reference, and we add a disclaimer that the
database is for public domain use only and can be copied freely by
referencing it. Supplementary data are available at
https://doi.org/10.1594/PANGAEA.885492 (Rahmati et al., 2018). Data
quality assessment is strongly advised prior to any use of this database.
Finally, we would like to encourage scientists to extend and update the SWIG database
by uploading new data to it.
Agricultural land preparation and weed control techniques are essential farm management tools that affect the dynamics of soil water infiltration and the estimation accuracy of infiltration models. ...To analyse the interaction effect of tillage and weed control methods on the changes in soil physical properties and the efficacy of infiltration models, an experiment was conducted on a sandy clay loam forest ochrosol at Hodzo near Ho in Ghana. Four tillage systems (No Tillage NT, Reduced Tillage RT, Plough + Harrow + Ridging PHR, and Deep Tillage + Plough + Harrow + Ridging DPHR) and three weed control methods (Hoeing H, Machete MAT and No Weeding NW) were employed. The study also tested the reliability of the models (Kostiakov, Philip, and Horton) using the goodness of fit statistical criteria: Root mean squared error (RMSE), Mean absolute error (MAE), Coefficient of determination (R2), and Nash-Sutcliffe efficiency (NSE). The results show that conservation tillage systems (CsT) and conventional tillage systems (CT) with MAT weeding treatments recorded the highest moisture content across the studied soil profile, especially for NT x MAT (11.189%) which was significant (p < 0.05) in the 15-30 cm layer; the lowest were observed in the CsT and CT with H weeding interactions, especially for the DPHR x H (8.086%). Comparing the interaction effect on the soil infiltration, the highest mean infiltration rate was significant (p < 0.05) under the NT X H treatment combination whilst the lowest infiltration rate was recorded in the DPHR X H and PHR X NW treatment combinations. The efficiency of the fitting models (Kostiakov > Horton > Philip) highly prioritised the soil tillage operations and weed management under the treatments DPHR x MAT > DPHR x NW > DPHR x H > RT x MAT > PHR x NW > PHR x MAT > NT x NW > RT x MAT > PHR x H > RT x H > NT x MAT > RT x NW > NT x H in that order. The trend shows that the increase in tillage intensity and the decrease in weed management intensity induce the quality of the estimation process and vice versa. The study, therefore, identified the use of machete (MAT) with DPHR under the Kostiakov model as the efficient land management for modelling the cumulative infiltration characteristics of the sandy clay loam ochrosols of the study area.
Obesity and insulin resistance have been linked to a low-grade chronic inflammatory response characterized by increased macrophage infiltration, altered cytokine production and activation of ...inflammatory signaling pathway in adipose tissue. Pharmacological agents and natural products that are capable of reducing inflammatory activity possess anti-diabetic properties. Luteolin, a naturally occurring flavonoid, has been demonstrated to inhibit lipopolysaccharide-induced tumor necrosis factor-a (TNFa) release and activation of NF- Kappa B pathway in macrophages. However, little is known about the mechanism and effect of luteolin on inflammation-related insulin resistance in adipocytes. In this study, we investigated the effect of luteolin on insulin action in 3T3-L1 adipocytes and primary adipose cells. Here we showed that luteolin treatment for 24 h increased the response of glucose uptake to insulin stimulation in 3T3-L1 adipocytes. Our results also demonstrated that luteolin enhanced Akt2 phosphorylation in an insulin-stimulated state. Furthermore, luteolin treatment decreased mRNA levels of TNFa, interleukin-6 and MCP-1, while it increased the gene expression of adiponectin and leptin in 3T3-L1 adipocytes and primary mouse adipose cells. Most interestingly, we found that treatment of luteolin markedly enhanced peroxisome proliferator-activated receptor g (PPARg) transcriptional activity in 3T3-L1 adipocytes, and luteolin-increased expression of adiponectin and leptin was blocked by GW9662, a PPARg antagonist. Thus, our data suggest that luteolin influences insulin action and production of adipokines/cytokines in adipocytes by activating the PPARg pathway.
Extramedullary (EM) manifestations of acute leukemia include a wide variety of clinically significant phenomena that often pose therapeutic dilemmas. Myeloid sarcoma (MS) and leukemia cutis (LC) ...represent 2 well-known EM manifestations with a range of clinical presentations. MS (also known as granulocytic sarcoma or chloroma) is a rare EM tumor of immature myeloid cells. LC specifically refers to the infiltration of the epidermis, dermis, or subcutis by neoplastic leukocytes (leukemia cells), resulting in clinically identifiable cutaneous lesions. The molecular mechanisms underlying EM involvement are not well defined, but recent immunophenotyping, cytogenetic, and molecular analysis are beginning to provide some understanding. Certain cytogenetic abnormalities are associated with increased risk of EM involvement, potentially through altering tissue-homing pathways. The prognostic significance of EM involvement is not fully understood. Therefore, it has been difficult to define the optimal treatment of patients with MS or LC. The timing of EM development at presentation versus relapse, involvement of the marrow, and AML risk classification help to determine our approach to treatment of EM disease.
Hydrologic regulation of plant rooting depth Fan, Ying; Miguez-Macho, Gonzalo; Jobbágy, Esteban G. ...
Proceedings of the National Academy of Sciences - PNAS,
10/2017, Letnik:
114, Številka:
40
Journal Article
Recenzirano
Odprti dostop
Plant rooting depth affects ecosystem resilience to environmental stress such as drought. Deep roots connect deep soil/groundwater to the atmosphere, thus influencing the hydrologic cycle and ...climate. Deep roots enhance bedrock weathering, thus regulating the long-term carbon cycle. However, we know little about how deep roots go and why. Here, we present a global synthesis of 2,200 root observations of >1,000 species along biotic (life form, genus) and abiotic (precipitation, soil, drainage) gradients. Results reveal strong sensitivities of rooting depth to local soil water profiles determined by precipitation infiltration depth from the top (reflecting climate and soil), and groundwater table depth from below (reflecting topography-driven land drainage). In well-drained uplands, rooting depth follows infiltration depth; in waterlogged lowlands, roots stay shallow, avoiding oxygen stress below the water table; in between, high productivity and drought can send roots many meters down to the groundwater capillary fringe. This framework explains the contrasting rooting depths observed under the same climate for the same species but at distinct topographic positions. We assess the global significance of these hydrologic mechanisms by estimating root water-uptake depths using an inverse model, based on observed productivity and atmosphere, at 30″ (∼1-km) global grids to capture the topography critical to soil hydrology. The resulting patterns of plant rooting depth bear a strong topographic and hydrologic signature at landscape to global scales. They underscore a fundamental plant–water feedback pathway that may be critical to understanding plant-mediated global change.
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