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• A longer calibration period is required for catchments with nonstationary rainfall-runoff relationships to achieve stable simulations. • With the increase in the length of the interval between the calibration and transfer periods, the transferability of the model decreases gradually. • When forecasting runoff under nonstationary rainfall-runoff relationships, the closeness of the total rainfall amount between calibration and transfer periods is more important than the similarity in rainfall processes. Changing climatic conditions have changed the stationary rainfall-runoff relationships in many basins. In this context, the value of the model parameters will depend more on the selection of the calibration period, which directly affects the accuracy of runoff forecasting. However, systematic exploration and testing of the impact of calibration conditions on the transferability of hydrological models under stationary and nonstationary climatic conditions require more effort. The present study investigates the impact of four calibration conditions on model transferability, including the length of the calibration period, the length of the interval between the calibration and transfer periods, the difference in climate conditions as measured by the total rainfall amount between the calibration and transfer periods, and the difference in the similarity of rainfall processes between the calibration and transfer periods. Two catchments with stationary and nonstationary climatic conditions, and five models, including XAJ, HBV, IHACRES, SIMHYD and GR4J, are used in this study. The results show that (1) a longer calibration period is required for catchments with nonstationary rainfall-runoff relationships to achieve stable simulations; (2) with the increase in the length of the interval between the calibration and transfer periods, the transferability of the model decreases gradually, and the degree of reduction is greater for catchments with nonstationary climatic conditions and rainfall-runoff relationships; and (3) when forecasting future runoff under nonstationary rainfall-runoff relationships, the closeness of the total rainfall amount between the calibration and transfer periods is more important than the similarity in rainfall series between the calibration and transfer periods. This study provides insight into the impact of calibration conditions on the transferability of hydrological models in the context of climate change. [ABSTRACT FROM AUTHOR]

• An evaluation method of model transferability is proposed. • The complex models (XAJ and HBV) have better spatial transferability than the simple model (GR4J). • The performance of models transferred from the wettest to the driest period is worse than that of models transferred from the driest to the wettest period. Changing conditions of the climate and underlying surface have altered the rainfall-runoff relationships in many basins, greatly increasing additional challenges in the applicability of hydrological models for studying the hydrological response to those potential changes. However, systematic and simultaneous testing and comparing of both temporal and spatial transferabilities of different hydrological models under changing conditions have not received enough attention. The present study investigates the potential differences between temporal and spatial transferabilities of different hydrological models under different climatic and underlying surface conditions, which are synthesized from two basins in Southern China with 50-year historical records (1966–2015). The transferability of five hydrological models, i.e., XAJ, HBV, SIMHYD, IHACRES and GR4J, is investigated under the synthesised changing conditions by using a new evaluation method, proposed in this study. The results show that: (1) the proposed evaluation method is proved to be effective in evaluating the transferability of the models; (2) for temporal transferability under stationary condition, the five models show similar performances, but for spatial transferability, the performances of complex models (XAJ and HBV) are better than that of the simple model (GR4J); (3) the difference in underlying surface conditions in the target basin affects spatial transferability of the models; (4) hydrological models have much better transferability from dry to wet period than otherwise. This study provides an insight to test temporal and spatial transferabilities of hydrological models in the context of changing climate and underlying surface conditions. [ABSTRACT FROM AUTHOR]

Non-stationary hydrological sequences and rainfall-runoff relationship in a changingenvironment have brought new challenges to the application of hydrological models. Robusthydrological models are more reliable to evaluate the impact of changing environment onwater resources at the catchment scale. However, robustness differences in hydrologicalresponses to changing environment resulting from the use of different hydrological modelshave received much less attention. Therefore, this study compares the robustness of sixconceptual hydrological models (Xinanjiang, HBV, SIMHYD, IHACRES, GR4J andWASMOD) in different test scenarios in the Yellow River Basin and the Yangtze River Basinof China. The hierarchical scheme for systematic testing of hydrological models according tothe modelling tasks proposed by Klemes (1986) and 48-year long records of daily runoff andclimate are used in this study. Firstly, as the least challenging test in hierarchical scheme, thesimple split-sample test is performed for testing models’ ability to reproduce historicalrunoff under stationary conditions. Secondly, the proxy-basin test is carried out as abasic test for geographical transferability. In order to avoid the influence causedby the climate change, the single years of a basin are calibrated and the doubleyears of other basins are validated. Thirdly, the climate comparison periods (thedriest and wettest five years in a row) are selected as calibration and validationperiods. The differential split-sample test and proxy-basin differential split-sampletest are executed when calibration and validation occur in the same basin and indifferent basins respectively. By comparing the performance of different models in fourtests, more stable models can be selected and used in future studies. This study canprovide useful information for model selection and increase the credibility of modelsabout the research of hydrological impacts produced by changing environment. [ABSTRACT FROM AUTHOR]

The extract of Moringa oleifera (M. oleifera) seeds exerts various pharmacological effects. Our previous study demonstrated that M. oleifera seed extract (MSE) alleviates scopolamine-induced learning and memory impairment in mice. In the present study, we investigate the neuropharmacological properties of 70% ethanolic MSE in the acute and delayed stages of ischemic stroke. MSE may be effective for the prevention and/or treatment of acute ischemic stroke. The most effective dose was 500 mg/kg, and the therapeutic window seemed to be within 4 h after reperfusion. Additionally, we found that MSE treatment improved animal survival, reversed spatial cognitive impairment and promoted hippocampal neurogenesis and neuroplasticity as well as the cholinergic neurotransmission system during the recovery stages of ischemic stroke. Our findings verified that MSE has neuroprotective effects in both the acute and chronic stages of ischemic stroke. The relevant mechanism of protection may occur by promoting hippocampal neurogenesis and synaptic plasticity as well as improving cholinergic function. These findings suggest that M. oleifera seed extract may be a promising neuroprotective agent for the treatment of ischemic stroke. • Our study verified that MSE has neuroprotective effects in both the acute and chronic stages of ischemic stroke. • The relevant mechanism of protection of MSE may occur by promoting hippocampal neurogenesis and synaptic plasticity as well as improving cholinergic function [ABSTRACT FROM AUTHOR]

The spatial variability in soil pH in China is characterized by (i) soils in southern China being acidic to strongly acidic, (ii) soils in northern China being natural or alkaline, and (iii) soils in northeastern forested areas also being acidic (pH HT ht 7.2). Based on the SoilGrids and GSDE (Global Soil Dataset for Earth System Models; Shangguan et al., 2014) datasets, Dai et al. (2019) produce six soil layers with a spatial resolution of HT ht arcsec. CCAM includes 120 HT ht catchment attributes, including soil, land cover, geology, climate indices, and topography for each catchment. Table B1 Mean monthly solar radiation, HT ht (in mm), of evaporable water per day. [Extracted from the article]

Graphical abstract Highlights • Moringa oleifera Stem Extracts (MSE) protected HaCaT cells against H 2 O 2 exposure induced oxidative stress injury. • Topical treatment with MSE alleviated UVB-induced epidemic oxidative stress injury. • The protective effects of MSE are mediated by enhancement of antioxidant defense systems and activation of PPARα in skin keratinocytes. Abstract Oxidative stress is an important cause of skin injury induced by UVB radiation. Moringa oleifera also known as horseradish tree or drumstick tree, have multiple nutraceutical or pharmacological functions. However, whether Moringa oleifera protects skin against oxidative stress injury remains unknown. To investigate the effects of the ethanol extract of Moringa oleifera stem (MSE) on skin oxidative stress injury and its molecular mechanism, we first determined the effect of MSE on epidermal oxidative stress injury induced by H 2 O 2 in keratinocytes (HaCaT cells) and by UVB-radiation in mice. Then we investigated the effect of MSE on the enhancement of antioxidant system and activation of PPARα in vitro and in vivo. Furthermore, the flavonoids compositions in MSE were assayed by high-performance liquid chromatography (HPLC), and then molecular docking study was used to assess the major component in MSE to activate PPARα. Our results indicate that MSE (100–400 μg/mL) protected the epidemic cell against oxidative stress injury in vitro and topical treatment with MSE cream (6%) inhibit UVB-induced oxidative stress injury in the epidermis of the mouse skin. PPARα activation is involved in the protective effect of MSE. HPLC assay and molecular docking study indicated that rutin might be the main component in MSE to activate PPARα. These results confirm that MSE exerts the protective effect on oxidative stress induced skin keratinocytes injury. Moreover, the protective effect of MSE is mediated by enhancement of antioxidant defense systems and activation of PPARα in skin keratinocytes. [ABSTRACT FROM AUTHOR]

Propane-2-sulfonic acid octadec-9-enyl-amide (N15), an analogue of oleoylethanolamide (OEA), is a novel PPARα/γ dual agonist. Our previous studies verified the positive effects of OEA on the acute and delayed stages of cerebral ischemia. However, it is not clear whether N15 is effective against ischemic cerebral injury. In the present study, male Kunming mice were subjected to middle cerebral artery occlusion (MCAO). To evaluate its preventive effects, N15 (50, 100 or 200 mg/kg, ip ) was administered for 3 days before ischemia. To evaluate its therapeutic effects, N15 (200 mg/kg, ip ) was administered 1 h before reperfusion or 0, 1, 2 or 4 h after reperfusion. Neurological deficit scores, infarct volume and the degree of brain oedema were determined at 24 h after reperfusion. Blood brain barrier (BBB) disruption was evaluated by Evans blue (EB) and FITC-dextran leakages at 6 h after reperfusion. The activation/inflammatory responses of microglia/macrophages were detected using immunohistochemistry and western blot. N15 pretreatment improved neurological dysfunction, reduced infarct volume and alleviated brain oedema in a dose-dependent manner; the most effective dose was 200 mg/kg. The therapeutic time window was within 2 h after reperfusion. N15 treatment preserved the BBB integrity and suppressed the activation of microglia/macrophages. N15 inhibited inflammatory cytokine expression not only in MCAO mice but also in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. Additionally, N15 markedly decreased the phosphorylation levels of NF-κBp65, STAT3, and ERK1/2 both in vivo and in vitro . Furthermore, the PPARα antagonist MK886 or PPARγ antagonist T0070907 respectively partly abolished the anti-inflammatory effects of N15 in vitro . Our findings demonstrated that N15 can exert neuroprotective effects against cerebral ischemic insult. Moreover, the neuroprotective effects of N15 on cerebral ischemia may be attributed to its anti-inflammatory properties, at least in part, by enhancing PPARα/γ dual signaling and inhibiting the activation of the NF-κB, STAT3, and ERK1/2 signaling pathways. These findings suggest that N15 may be a potential therapeutic choice for the prevention and treatment of ischemic stroke. [ABSTRACT FROM AUTHOR]

Abstract: Oleoylethanolamide (OEA) is a high-affinity agonist of peroxisome proliferator-activated receptor α (PPARα) which may act as an endogenous neuroprotective factor. However, it is not clear whether orally administered OEA is effective against ischemic brain injury. In our study, transient focal cerebral ischemia was induced by middle cerebral artery occlusion for 90 min followed by reperfusion. To evaluate its preventive effects, OEA (10, 20 or 40mg/kg, ig) was administered for 3 days before ischemia. To evaluate its therapeutic effects, OEA (40mg/kg, ig) was administered at 0.5 or 1h before reperfusion or at 0 or 1h after reperfusion. In some experiments, the PPARα antagonist MK886 (10mg/kg, ig) was administered 0.5h before OEA. Neurological deficit score, infarct volume and brain edema degree were determined at 24h after reperfusion. Blood–brain barrier (BBB) disruption was evaluated by Evans blue (EB) leakage at 6h after reperfusion. Real-time RT-PCR and western blot were performed to detect PPARα mRNA and protein expression. Oral OEA pretreatment improved neurological dysfunction reduced infarct volume and alleviated brain edema in a dose-dependent manner; the most effective dose was 40mg/kg. The therapeutic time is within 1h after reperfusion. OEA also increased PPARα mRNA and protein expression in the ischemic brain. The PPARα antagonist MK886 abolished the protective effects of OEA. In conclusion, our results indicate that orally administered OEA protects against acute cerebral ischemic injury in mice, at least in part by activating PPARα. [Copyright &y& Elsevier]