Spatiotemporal heterogeneity in meteorological and hydrological drought patterns and propagations influenced by climatic variability, LULC change, and human regulations.

This study aims to quantify meteorological-hydrological drought propagations and examine the potential impacts by climatic variability, LULC change (LULC), and human regulations. An integrated observation-modeling framework quantifies drought propagation intervals and assesses mechanisms influencing hydrological droughts. Meteorological droughts are characterized using the Standardized Precipitation Evapotranspiration Index (SPEI), and hydrological droughts are assessed through the Standardized Streamflow Index (SSI) across diverse climatic zones. Cross-correlation analysis between SPEI and SSI time series identifies the lag time associated with the highest correlation as the drought propagation interval. Mechanisms are investigated via a coupled empirical-process modeling framework incorporating the Soil and Water Assessment Tool (SWAT). Discrepancies between simulated and observed SSI time series help quantify the extent of human regulation impacts on hydrological drought characteristics and propagation. The Yellow River Basin (YRB), divided into six subzones based on climate characteristics, is selected as the case study. Key findings include: (1) Meteorological droughts were extremely severe across most YRB during the 1990s, while the 2000s showed some mitigation primarily due to precipitation increases. (2) Hydrological droughts and propagation times from meteorology to hydrology demonstrated substantial spatiotemporal variability. In general, summer propagation times were shorter than other seasons. (3) Propagation times were shorter in arid regions with cropland or built-up land cover versus grassland and woodland, while the reverse held for humid regions. (4) Human regulations prolonged propagation times, likely due to reservoir regulations designed to overcome water deficits. While the YRB is the focus of this paper, the methodologies and findings are applicable to other regions worldwide to enhance drought forecasting and water resource management. In various hydrological and climatic contexts worldwide.

The impact of technology on promoting physical activities and mental health: a gender-based study.

BACKGROUND: Physical inactivity is a significant public health concern globally, associated with an increased risk of chronic diseases and detrimental effects on both physical and mental health. Technologically based interventions have emerged as a potential solution to promote physical activity engagement and improve mental health outcomes. However, understanding the effectiveness of these interventions and the role of gender in their outcomes is essential for developing tailored strategies. OBJECTIVE: This study aims to examine the effectiveness of technologically based interventions in promoting physical activity and improving mental health outcomes, with a specific focus on gender differences. METHODOLOGY: This study employed a three-phase mixed methods research design. Phase one was an experimental phase where 300 participants were randomly assigned to intervention or control groups. The intervention group received a technologically based physical activity intervention, while the control group did not. Physical activity levels and mental health outcomes were assessed before and after the intervention. Phase two involved qualitative interviews with a subset of participants (n = 20) from the intervention group. These interviews explored motivations and barriers to physical activity, aiming to uncover personal factors influencing engagement. Thematic analysis was used to identify recurring themes. Phase three utilized a quantitative survey to compare motivations and barriers between males and females. The survey, administered to a larger sample, included participants from both intervention and control groups. It assessed various factors and allowed for a quantitative comparison of gender differences. FINDINGS: findings indicated that the intervention improved the mental health and physical activities level of the intervention groups. Findings also there are 8 motivations for and barriers to using technology in physical activities. Male and females' scores on some of the motivations and barriers were statistically significant. CONCLUSION: technology plays an important role in improving the mental health and physical activities of adults. Findings can be used by health care centers, digital psychologists, and physical trainers.

Preparation and Properties of Municipal Solid Waste Incineration Alkali-Activated Lightweight Materials through Spontaneous Bubbles.

A self-foaming alkali-activated lightweight material was prepared by the pretreatment of municipal solid waste incineration bottom ash (BA). The low weight could be achieved without adding a foaming agent by using the low-density and self-foaming expansion characteristics of BA in combination with a strong alkali. The effects of BA, liquid sodium silicate (LSS), and calcium hydroxide (CH) on dry and wet densities, as well as water absorption, are discussed. The results show that increasing the BA content can significantly improve the foaming effect and reduce the dry and wet densities of specimens. However, it also leads to a sudden decrease in compressive strength and a significant increase in water absorption. LSS and CH can significantly improve the ability to seal bubbles by accelerating condensation, and they further reduce dry and wet densities without significantly improving water absorption. It is most effective at BA, LSS, and CH contents of 60, 20, and 2%, respectively.

Establishment of watershed ecological water requirements framework: A case study of the Lower Yellow River, China.

It is of great practical significance to ensure ecological water requirements (EWRs) for the maintenance of river health and the sustainable development of human socioeconomics. How to scientifically determine the comprehensive EWRs and estimate the uncertainty of hydro-ecological tools performed in the process of conducting remains one of the most important yet most complicated issues. In this study, the ecological water requirements framework (EWRsF) of the Lower Yellow River (LYR), which considers instream ecological base flow, survival and reproduction of indicator fish species, equilibrium of erosion and siltation and ecological function of the estuary, was constructed by integrating hydrological, hydraulic and ecological habitat methods. The framework contains three crucial components - determination of instream EWRs and estuarine EWRs, uncertainty analysis of hydro-ecological tools. For instream ecological base flow, we proposed an improved Tennant method, which took into account both seasonality and sediment transport characteristics of the LYR, and could better reflect the actual hydrological regime. For the hydrological ecological response relationship of indicator fish species, we estimated the uncertainty of the model output of River2D to improve its credibility of the simulation results. The results demonstrated that: 1) Two-grade intra-annual monthly EWRs process of suitable and minimum for four instream sections and estuary area were obtained. The flood season (June-October) is the period with the largest proportion of intra-annual instream EWRs, whereas in estuary area, is the spawning period (April-July) of dominant species. 2) The uncertainty of HSI curves directly leads to the uncertainty of model output. Although the shape and position of the WUA curve can be uncertain, it does not affect the judgment of EWRs threshold. 3) The research results can provide scientific basis for water resource management decision-making in the LYR. Additionally, the ideas also have reference significance for similar basins.

Field-applied biochar-based MgO and sepiolite composites possess CO2 capture potential and alter organic C mineralization and C-cycling bacterial structure in fertilized soils.

Agricultural soils contribute a significant amount of anthropogenic CO2 emission, a greenhouse gas of global environmental concern. Hence, discovering sustainable materials that can capture CO2 in cultivated soils is paramount. Since the effect of biochar on C mineralization/retention in fertilized soils is unclear, we produced biochar-based MgO and sepiolite-nanocomposites with CO2 capture potential. The field-scale impacts of the modified-biochars were evaluated on net C exchange rate (NCER) periodically for 3 months in fertilized plots. The effects of the modified-biochar on organic-C mineralization, the activities, and dynamics of C-cycling-related 16S rRNA which are unknown, were investigated. Results revealed an initial rapid and higher cumulative CO2 emission from the sole fertilizer treatment (F). Unlike the biochar treatment (BF), the successful incorporation of MgO/Mg(OH)2 nanoparticles into the matrix and surface of biochar, and the potential formation of MgCO3 with soil CO2, mitigated CO2 emission, especially in the MgO-modified biochar (MgOBF), compared to the sepiolite-biochar treatment (SBF). Compared to F and BF, the higher C retention as MgCO3 in the modified biochar treatments led to an increase in cellulase activity, stimulation of key C-cycling-related bacteria, and the expression of genes associated with starch, sucrose, amino sugar, nucleotide sugar, ascorbate, aldarate, cellulose, and chitin degradation, thus, increasing organic C mineralization. Among the modified-biochar treatments, higher C mineralization was recorded in SBF, resulting in increased cumulative CO2 emission, despite its initial capture for up to 42 days. However, MgOBF was effective in capturing soil-derived CO2, despite the increased C mineralization compared to biochar. The changes in soil moisture and temperature significantly regulated NCER. Also, the modified biochars positively influenced the distribution of C-cycling-related bacteria by improving soil pH and available nutrients. Among the modified biochars, the observed higher mitigation effect of MgOBF on NCER indicated that it could be preferably applied in agricultural soils.

Auxiliary subunits control biophysical properties and response to compound NS5806 of the Kv4 potassium channel complex.

Kv4 pore-forming subunits co-assemble with ß-subunits including KChIP2 and DPP6 and the resultant complexes conduct cardiac transient outward K+ current (Ito). Compound NS5806 has been shown to potentate Ito in canine cardiomyocytes; however, its effects on Ito in other species yet to be determined. We found that NS5806 inhibited native Ito in a concentration-dependent manner (0.1~30 µM) in both mouse ventricular cardiomyocytes and human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), but potentiated Ito in the canine cardiomyocytes. In HEK293 cells co-transfected with cloned Kv4.3 (or Kv4.2) and ß-subunit KChIP2, NS5806 significantly increased the peak current amplitude and slowed the inactivation. In contrast, NS5806 suppressed the current and accelerated inactivation of the channels when cells were co-transfected with Kv4.3 (or Kv4.2), KChIP2 and another ß-subunit, DPP6-L (long isoform). Western blot analysis showed that DPP6-L was dominantly expressed in both mouse ventricular myocardium and hiPSC-CMs, while it was almost undetectable in canine ventricular myocardium. In addition, low level of DPP6-S expression was found in canine heart, whereas levels of KChIP2 expression were comparable among all three species. siRNA knockdown of DPP6 antagonized the Ito inhibition by NS5806 in hiPSC-CMs. Molecular docking simulation suggested that DPP6-L may associate with KChIP2 subunits. Mutations of putative KChIP2-interacting residues of DPP6-L reversed the inhibitory effect of NS5806 into potentiation of the current. We conclude that a pharmacological modulator can elicit opposite regulatory effects on Kv4 channel complex among different species, depending on the presence of distinct ß-subunits. These findings provide novel insight into the molecular design and regulation of cardiac Ito. Since Ito is a potential therapeutic target for treatment of multiple cardiovascular diseases, our data will facilitate the development of new therapeutic Ito modulators.

Comparison of diagnostic values of ultrasound micro-flow imaging and contrast-enhanced ultrasound for neovascularization in carotid plaques.

The aim of the present study was to compare the diagnostic values of ultrasound micro-flow imaging (SMI) and contrast-enhanced ultrasound (CEUS) for neovascularization in carotid plaques, and to investigate their capacities for predicting the risks of cerebral stroke. A total of 39 patients (64 carotid plaques) with severe carotid artery stenosis undergoing carotid endarterectomy were selected between February 2015 and February 2016, and SMI and CEUS were used to detect neovascularization in plaques. According to the CEUS dynamic graph of plaques, the enhanced intensity visual scales and contrast parameters were obtained. Carotid atherosclerotic plaques were divided into 4 groups. The differences in the enhanced intensity visual scales, contrast parameters, and gray-scale median (GSM) values among the 4 groups were analyzed. Carotid plaque tissue samples from patients were stained for CD34, and the consistency of the methods for the diagnosis of neovascularization in plaques was analyzed. The differences in GSM values, enhanced intensities, and enhanced densities among the 4 groups of plaques were statistically significant (F=29.365, χ2=29.025, χ2=30.871, P<0.001); the differences in enhanced intensities of carotid atherosclerotic plaques with different echo types were statistically significant (χ2=17.951, P<0.001). The enhanced intensity of plaques was negatively correlated with the GSM value (r=-0.376, P<0.01), and the enhanced density of plaques was negatively correlated with the GSM value (r=-0.252, P<0.01). SMI and CEUS grading had good consistency (κ=0.860>0), there were statistically significant differences in new vessel densities with different SMI gradings (P<0.001), and the clinical symptoms and severity were positively correlated with SMI grading (rs=0.592>0). In conclusion, SMI and CEUS have good consistency for evaluating neovascularization in carotid plaques, and have good clinical value for evaluating neovascularization in carotid plaques.

Inhibitory effect of compound NS5806 on cardiac transient outward potassium channel dependents on interaction between auxiliary subunits / 中国药理学与毒理学杂志

OBJECTIVE Transient outward potassium current (Ito) plays a crucial role in cardiac phase 1 repolarization and the channels are assembled by pore-forming α-subunits (Kv4.2 or Kv4.3) and auxiliary subunits (KChIP2 and DPP6). Previous studies have found that the compound NS5806 increases Ito in canine ventricular cardiomyocytes through slowing current decay. Here, we reported that NS5806 produced an acute inhibitory action on Ito in mouse ventricular cardiomyocytes and human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CM). METHODS Whole-cell patch-clamp was used to record Ito in native myocytes and in HEK cells expressing cloned Kv4.x/KChIP2/DPP6 channels; Western-blot detected the channel protein expression. RESULTS In isolated mouse ventricular cardiomyocytes, NS5806 (0.1-30 μmol·L-1) inhibited Ito in a concentration-dependent manner with IC50 of 6.6±1.9 μmol·L-1. The current decay was significantly accelerated with a time constant from 53.8±5.5 to 41.8±3.0 ms at +60 mV (P<0.01). Similarly, NS5806 concentration-dependently reduced the Ito peak current amplitude with an acceleration of current decay. In addition, NS5806 increased IKv4.2/KChIP2 and delayed current decay, but decreased IKv4.2/KChIP2/DPP6 with the acceleration of current decay. The inhibitory action on the current was more potent if DPP6 expression level was increased from Kv4.2/KChIP2/DPP61:1:1 to 1:1:3. Western-blot showed a higher expression of DPP6 protein in mouse heart and in hiPS- CM compared to canine heart. Moreover, specific knock- down DPP6 expression by siRNA antagonized the inhibitory action of NS5806 in hiPS-CM. Our results pointed to an important role of DPP6 subunit in the regulation of NS5806 on the channel. By using molecular docking simulation, five interaction sites with high possibility between KChIP2 and DPP6 were identified. Mutations of those sites changed the inhibitory action of NS58056 into excitatory effect on the current with the delay of current decay. CONCLUSION NS5806 significantly inhibits Ito by accelerating current decay in mouse cardiomyocytes and hiPS-CM. The effect depends on the interaction between DPP6 and KChIP2 subunits.

Aldosterone down-regulates the slowly activated delayed rectifier potassium current in adult guinea pig cardiomyocytes.

BACKGROUND AND PURPOSE: There is emerging evidence that the mineralocorticoid hormone aldosterone is associated with arrhythmias in cardiovascular disease. However, the effect of aldosterone on the slowly activated delayed rectifier potassium current (IK s ) remains poorly understood. The present study was designed to investigate the modulation of IK s by aldosterone. EXPERIMENTAL APPROACH: Adult guinea pigs were treated with aldosterone for 28 days via osmotic pumps. Standard glass microelectrode recordings and whole-cell patch-clamp techniques were used to record action potentials in papillary muscles and IK s in ventricular cardiomyocytes. KEY RESULTS: The aldosterone-treated animals exhibited a prolongation of the QT interval and action potential duration with a higher incidence of early afterdepolarizations. Patch-clamp recordings showed a significant down-regulation of IK s density in the ventricular myocytes of these treated animals. These aldosterone-induced electrophysiological changes were fully prevented by a combined treatment with spironolactone, a mineralocorticoid receptor (MR) antagonist. In addition, in in vitro cultured ventricular cardiomyocytes, treatment with aldosterone (sustained exposure for 24 h) decreased the IK s density in a concentration-dependent manner. Furthermore, a significant corresponding reduction in the mRNA/protein expression of IKs channel pore and auxiliary subunits, KCNQ1 and KCNE1 was detected in ventricular tissue from the aldosterone-treated animals. CONCLUSIONS AND IMPLICATIONS: Aldosterone down-regulates IK s by inhibiting the expression of KCNQ1 and KCNE1, thus delaying the ventricular repolarization. These results provide new insights into the mechanism underlying K(+) channel remodelling in heart disease and may explain the highly beneficial effects of MR antagonists in HF.

[Protective effect of sesamin against myocardial injury induced by cadmium chloride in rats].

OBJECTIVE: To investigate the protective effect of sesamin against cadmium chloride (CdCl2)-induced cardiotoxicity in rats. METHODS: Fifty male Wistar rats were randomly assigned to five groups: control group, CdCl2 group, and low-, middle-, and high-dose sesamin groups. The control group was given normal saline. The CdCl2 group and sesamin groups were intraperitoneally injected with CdCl2 (5 mg/kg×2 d), and the low-, middle-, and high-dose sesamin groups were given 20, 40, and 80 mg/kg sesamin, respectively. All treatments lasted for four weeks. ECG was measured by a physiological recorder, and serum myocardial enzyme levels were determined by biochemical assay. The heart was weighed, and heart tissues were used in histopathological examination and determination of malondialdehyde (MDA) level. RESULTS: Compared with the control group, the CdCl2 group showed significantly higher levels of serum CK and CK-MB, an increased heart coefficient, significant ST-segment elevation, and higher level of MDA in myocardial tissue (P < 0.05). Histopathological analysis showed edema of myocardial tissues and cells, myocardial fibers disorder, karyopyknosis, and uneven or deep staining of nuclear chromatin. Different doses of sesamin relieved the myocardial pathological changes induced by CdCl2, and high-dose sesamin was the most effective. The middle- and high-dose sesamin groups showed significantly reduced serum CK and CK-MB levels compared with the CdCl2 group (P < 0.05). The heart coefficient of the high-dose sesamin group (0.19±0.01%) was significantly lower than that of the CdCl2 group (0.21±0.01%) (P < 0.05). Myocardial MDA levels of the three sesamin groups (42.32±4.65, 36.71±5.34, and 33.12±4.62 nmol/mg pro, respectively) were all significantly lower than that of the CdCl2 group (55.87±3.65 nmol/mg pro) (P < 0.05). CONCLUSION: Sesamin can relieve myocardial injury induced by CdCl2, and one possible mechanism is the enhancement of antioxidant capacity of myocardial tissue.

Effects of low-dose spironolactone combined with irbesartan on cardiac hypertrophy induced by pressure overload in rats.

BACKGROUND: The mineralocorticoid receptor (MR) blockade in the heart is an attractive therapeutic option for the treatment of heart failure. However, the use of MR antagonist is limited by an increased incidence of hyperkalemia owing to MR blockade in the kidney. This study was designed to evaluate and compare the effectiveness of a low, non-pressure-lowering dose of spironolactone (Sp) with that of a conventional blood pressure-lowering dose combined with irbesartan on pathological cardiac remodeling as well as serum potassium level in pressure-overload rats. METHODS: The pressure-overloaded myocardial remodelling was produced by partial abdominal aortic constriction (PAAC) in rats. Four weeks after PAAC, animals were respectively treated with vehicle, irbesartan (15 mg/kg) alone, low-dose Sp (1 mg/kg) or conventional-dose of Sp (20 mg/kg) in combination with irbesartan for consecutive four weeks. RESULTS: The result demonstrated that compared to irbesartan monotherapy, the combination of irbesartan and spironolactone both in low- and conventional-dose exhibited additional cardioprotection against PAAC-induced cardiac remodelling. Low-dose spironolactone was as effective in inhibiting cardiac hypertrophy, fibrosis and in improving diastolic function as high dose. Low-dose spironolactone did not lead to a rise in potassium serum levels, but high dose did. CONCLUSIONS: This study suggests that combined low dose of spironolactone and irbesartan may be an effective and safety therapeutic strategy for cardiac hypertrophy and heart failure.