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1.
Sci Total Environ ; 947: 174705, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39002586

RESUMO

Groundwater irrigation districts, which play a crucial role in the Earth's critical zone, are confronted with numerous challenges, including water scarcity, pollution, and ecological degradation. These issues come from multiple systems and are linked to a groundwater-dominated water-food-environment-ecosystem nexus problem related to agricultural activities (WFEE). There is a pressing need for the scientific characterization and evaluation of the WFEE nexus in groundwater irrigation districts to assure high-quality, sustainable development. Furthermore, it is critical to provide practical and efficient regulations at the farmer level to uphold the health of this nexus. This paper presents a mapping network that focuses on groundwater irrigation districts. The network aims to convert the restriction indicators utilized to maintain the health of the WFEE nexus (at the irrigation district scale) into the targets employed to manage farmers' living and agricultural activities (at the farmer scale). Additionally, a system dynamics model is created to track and manage the interacting relationships between the WFEE nexus and farmers' living and agricultural activities. This proposed model employs a structured parameter system comprising targets, state parameters, regulatory parameters, and evaluation parameters. This system can get insight into the status of the WFEE nexus at the farmer level using state parameters, induce tailored management and regulation measures using regulatory parameters, assess the effectiveness of various measures using the evaluation parameters, and finally provide decision support to enhance the health of the WFEE nexus. The findings from the research conducted in the Yong'an groundwater irrigation district demonstrated that the model accurately described the relationship between the WFEE nexus and farmers' activities in groundwater irrigation districts. Furthermore, the model responded strongly to a variety of improvement strategies, including adjustments in planting area, optimization of planting pattern, improvement of irrigation method, and implementation of agronomic measures. As a result, it provided farmers with decision support for applying agricultural management methods and addressing the WFEE nexus problem in groundwater irrigation areas.

2.
J Contam Hydrol ; 265: 104385, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878553

RESUMO

This study aims to develop a multi-objective quantitative-qualitative reservoir operation model (MOQQROM) by a simulation-optimization approach. However, the main challenge of these models is their computational complexity. The simulation-optimization method used in this study consists of CE-QUAL-W2 as a hydrodynamic and water quality simulation model and a multi-objective firefly algorithm-k nearest neighbor (MOFA-KNN) as an optimization algorithm which is an efficient algorithm to overcome the computational burden in simulation-optimization approaches by decreasing simulation model calls. MOFA-KNN was expanded for this study, and its performance was evaluated in the MOQQROM. Three objectives were considered in this study, including (1) the sum of the squared mass of total dissolved solids (TDS), (2) the sum of the squared temperature difference between reservoir inflow and outflow as water quality objectives, and (3) the vulnerability index as a water quantity objective. Aidoghmoush reservoir was employed as a case study, and the model was investigated under three scenarios, including the normal, wet, and dry years. Results showed the expanded MOFA-KNN reduced the number of original simulation model calls compared to the total number of simulations in MOQQROM by more than 99%, indicating its efficacy in significantly reducing execution time. The three most desired operating policies for meeting each objective were selected for investigation. Results showed that the operation policy with the best value for the second objective could be chosen as a compromise policy to balance the two conflicting goals of improving quality and supplying the demand in normal and wet scenarios. In terms of contamination mass, this policy was, on average, 16% worse than the first policy and 40% better than the third policy in the normal scenario. In the wet scenario, it was, on average, 55% worse than the first policy and 16% better than the third policy. The outflow temperature of this policy was, on average, only 8.35% different from the inflow temperature in the normal scenario and 0.93% different in the wet scenario. The performance of the developed model is satisfactory.


Assuntos
Modelos Teóricos , Qualidade da Água , Abastecimento de Água , Algoritmos , Simulação por Computador
4.
Am J Physiol Gastrointest Liver Physiol ; 327(1): G16-G24, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38651230

RESUMO

Acute pancreatitis (AP) is a common disease with no targeted therapy and has varied outcomes ranging from spontaneous resolution to being lethal. Although typically painful, AP can also be painless. Various agents, including opioids, are used for pain control in AP; the risks and benefits of which are often debated. As experimental AP in mice is used to study the efficacy of potential therapies, we studied the effect of a commonly used opioid, buprenorphine, on the initiation and progression of AP. For this, we administered extended-release buprenorphine subcutaneously before inducing the previously established severe AP model that uses interleukins 12 and 18 (IL12,18) in genetically obese (ob/ob) mice and compared this to mice with AP but without the drug. Mice were monitored over 3 days, and parameters of AP induction and progression were compared. Buprenorphine significantly reduced serum amylase, lipase, pancreatic necrosis, and AP-associated fat necrosis, which is ubiquitous in obese mice and humans. Buprenorphine delayed the AP-associated reduction of carotid artery pulse distention and the development of hypothermia, hastened renal injury, and muted the early increase in respiratory rate versus IL12,18 alone. The site of buprenorphine injection appeared erythematous, inflamed, and microscopically showed thinning, loss of epidermal layers that had increased apoptosis. In summary, subcutaneous extended-release buprenorphine interfered with the induction of AP by reducing serum amylase, lipase, pancreatic and fat necrosis, the worsening of AP by delaying hypotension, hypothermia, while hastening renal injury, respiratory depression, and causing cutaneous injury at the site of injection.NEW & NOTEWORTHY Extended-release buprenorphine interferes with the initiation and progression of acute pancreatitis at multiple levels.


Assuntos
Buprenorfina , Pancreatite , Animais , Buprenorfina/farmacologia , Pancreatite/induzido quimicamente , Pancreatite/patologia , Camundongos , Analgésicos Opioides/farmacologia , Modelos Animais de Doenças , Masculino , Interleucina-12/metabolismo , Interleucina-18/metabolismo , Interleucina-18/sangue , Camundongos Obesos , Doença Aguda , Pâncreas/patologia , Pâncreas/efeitos dos fármacos , Camundongos Endogâmicos C57BL
5.
Sci Total Environ ; 923: 171528, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38460687

RESUMO

Different scenarios of precipitation, that lead to such phenomena as droughts and floods are influenced by concurrent multiple teleconnection factors. However, the multivariate relationship between precipitation indices and teleconnection factors, including large-scale atmospheric circulations and sea surface temperature signals in China, is rarely explored. Understanding this relationship is crucial for drought early warning systems and effective response strategies. In this study, we comprehensively investigated the combined effects of multiple large-scale atmospheric circulation patterns on precipitation changes in China. Specifically, Pearson correlation analysis and Partial Wavelet Coherence (PWC) were used to identify the primary teleconnection factors influencing precipitation dynamics. Furthermore, we used the cross-wavelet method to elucidate the temporal lag and periodic relationships between multiple teleconnection factors and their interactions. Finally, the multiple wavelet coherence analysis method was used to identify the dominant two-factor and three-factor combinations shaping precipitation dynamics. This analysis facilitated the quantification and determination of interaction types and influencing pathways of teleconnection factors on precipitation dynamics, respectively. The results showed that: (1) the Atlantic Multidecadal Oscillation (AMO), EI Niño-Southern Oscillation (ENSO), East Asia Summer Monsoon (EASM), and Indian Ocean Dipole (IOD) were dominant teleconnection factors influencing Standardized Precipitation Index (SPI) dynamics; (2) significant correlation and leading or lagging relationships at different timescales generally existed for various teleconnection factors, where AMO was mainly leading the other factors with positive correlation, while ENSO and Southern Oscillation (SO) were mainly lagging behind other factors with prolonged correlations; and (3) the interactions between teleconnection factors were quantified into three types: enhancing, independent and offsetting effects. Specifically, the enhancing effect of two-factor combinations was stronger than the offsetting effect, where AMO + NAO (North Atlantic Oscillation) and AMO + AO (Atlantic Oscillation) had a larger distribution area in southern China. Conversely, the offsetting effect of three-factor combinations was more significant than that of the two-factor combinations, which was mainly distributed in northeast and northwest regions of China. This study sheds new light on the mechanisms of modulation and pathways of influencing various large-scale factors on seasonal precipitation dynamics.

6.
Water Res ; 253: 121314, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38368733

RESUMO

Dam (reservoir)-induced alterations of flow and water temperature regimes can threaten downstream fish habitats and native aquatic ecosystems. Alleviating the negative environmental impacts of dam-reservoir and balancing the multiple purposes of reservoir operation have attracted wide attention. While previous studies have incorporated ecological flow requirements in reservoir operation strategies, a comprehensive analysis of trade-offs among hydropower benefits, ecological flow, and ecological water temperature demands is lacking. Hence, this study develops a multi-objective ecological scheduling model, considering total power generation, ecological flow guarantee index, and ecological water temperature guarantee index simultaneously. The model is based on an integrated multi-objective simulation-optimization (MOSO) framework which is applied to Three Gorges Reservoir. To that end, first, a hybrid long short-term memory and one-dimensional convolutional neural network (LSTM_1DCNN) model is utilized to simulate the dam discharge temperature. Then, an improved epsilon multi-objective ant colony optimization for continuous domain algorithm (ε-MOACOR) is proposed to investigate the trade-offs among the competing objectives. Results show that LSTM _1DCNN outperforms other competing models in predicting dam discharge temperature. The conflicts among economic and ecological objectives are often prominent. The proposed ε-MOACOR has potential in resolving such conflicts and has high efficiency in solving multi-objective benchmark tests as well as reservoir optimization problem. More realistic and pragmatic Pareto-optimal solutions for typical dry, normal and wet years can be generated by the MOSO framework. The ecological water temperature guarantee index objective, which should be considered in reservoir operation, can be improved as inflow discharge increases or the temporal distribution of dam discharge volume becomes more uneven.


Assuntos
Aprendizado Profundo , Ecossistema , Animais , Humanos , Algoritmos , Modelos Teóricos , Água
8.
Chembiochem ; 25(4): e202400074, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38293899

RESUMO

The synthesis of diarylamine-based organoselenium compounds via the nucleophilic substitution reactions has been described. Symmetrical monoselenides and diselenides were conveniently synthesized by the reduction of their corresponding selenocyanates using sodium borohydride. Selenocyanates were obtained from 2-chloro acetamides by the nucleophilic displacement with potassium selenocyanate. Selenides were synthesized by treating the 2-chloro acetamides with in situ generated sodium butyl selenolate as nucleophile. Further, the newly synthesized organoselenium compounds were evaluated for their glutathione peroxidase (GPx)-like activity in thiophenol assay. This study revealed that the methoxy-substituted organoselenium compounds showed significant effect on the GPx-like activity. The catalytic parameters for the most efficient catalysts were also determined. The anti-ferroptotic activity for all GPx-mimics evaluated in a 4-OH-tamoxifen (TAM) inducible GPx4 knockout cell line using liproxstatin as standard.


Assuntos
Ferroptose , Compostos Organosselênicos , Glutationa Peroxidase/metabolismo , Aminas , Compostos Organosselênicos/farmacologia , Antioxidantes/metabolismo , Acetamidas
9.
Pancreatology ; 24(1): 14-23, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37981523

RESUMO

OBJECTIVE: Non-steroidal anti-inflammatory drugs (NSAIDs) are the most studied chemoprophylaxis for post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). While previous systematic reviews have shown NSAIDs reduce PEP, their impact on moderate to severe PEP (MSPEP) is unclear. We conducted a systematic review and meta-analysis to understand the impact of NSAIDs on MSPEP among patients who developed PEP. We later surveyed physicians' understanding of that impact. DESIGN: A systematic search for randomized trials using NSAIDs for PEP prevention was conducted. Pooled-prevalence and Odds-ratio of PEP, MSPEP were compared between treated vs. control groups. Analysis was performed using R software. Random-effects model was used for all variables. Physicians were surveyed via email before and after reviewing our results. RESULTS: 7688 patients in 25 trials were included. PEP was significantly reduced to 0.598 (95%CI, 0.47-0.76) in the NSAIDs group. Overall burden of MSPEP was reduced among all patients undergoing ERCP: OR 0.59 (95%CI, 0.42-0.83). However, NSAIDs didn't affect the proportion of MSPEP among those who developed PEP (p = 0.658). Rectal Indomethacin and diclofenac reduced PEP but not MSPEP. Efficacy didn't vary by risk, timing of administration, or bias-risk. Survey revealed a change in the impression of the effect of NSAIDs on MSPEP after reviewing our results. CONCLUSIONS: Rectal diclofenac or indomethacin before or after ERCP reduce the overall burden of MSPEP by reducing the pool of PEP from which it can arise. However, the proportion of MSPEP among patients who developed PEP is unaffected. Therefore, NSAIDs prevent initiation of PEP, but do not affect severity among those that develop PEP. Alternative modalities are needed to reduce MSPEP among patients who develop PEP.


Assuntos
Diclofenaco , Pancreatite , Humanos , Diclofenaco/uso terapêutico , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Administração Retal , Anti-Inflamatórios não Esteroides/uso terapêutico , Indometacina/uso terapêutico , Pancreatite/epidemiologia , Pancreatite/etiologia , Pancreatite/prevenção & controle
10.
Sci Total Environ ; 912: 169283, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38110096

RESUMO

This study coupled the green water and blue water accounting with the existing standard Budyko framework and Fu's 1-parameter Budyko framework to diagnose the basin hydrological behavior. Both Budyko frameworks were employed to determine green water consumption (ETGreen) and blue water consumption (ETBlue) which, in turn, were used to map the blue water index (BWI) hotspots and green water index (GWI) bright spots. The relative contributions of green water and blue water were quantified for sustaining water and food security. A new methodology is proposed using BWI and GWI for partitioning the Gross Primary Production (GPP) and Water Use Efficiency (WUE) into GPPBlue, GPPGreen and WUEBlue and WUEGreen. The methodology was applied to five sub-basins of the Central Godavari River Basin (CGRB): Purna, Dhalegaon, GR Bridge, Yeli and Delta. Results showed that all five basins exhibited larger deviations from the theoretical Budyko curve of Fu's 1-parameter Budyko framework than did the standard Budyko framework and the Dhalegaon basin showed the largest deviations. The partitioning of GPP and WUE by the proposed methodology showed that the proportion of GPPGreen to the total GPP was much higher than that of the GPPBlue. Similarly, the proportion of WUEGreen to WUE was more than that of WUEBlue. The mapping of GPPBlue and GPPGreen, and WUEBlue and WUEGreen showed that the Delta and Yeli basins had the highest values of both GPPGreen & GPPBlue and WUEBlue and WUEGreen (bright spot basins) and the Dhalegaon and parts of GR Bridge basin had the lowest values (hot spot basins). The proposed partitioning of GPP and WUE will help identify the relative contributions of green water and blue water (for managing agricultural waters) and formulate agronomical and engineering practices for stakeholders and policy makers for increasing the overall WUE and GPP to sustain water and food security.


Assuntos
Hidrologia , Água , Agricultura , Rios , Segurança Alimentar
11.
Environ Monit Assess ; 195(12): 1438, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37943470

RESUMO

Under climate change, drought assessment, which can address nonstationarity in drought indicators and anthropogenic implications, is required to mitigate drought impacts. However, the development of drought indices for a reliable drought assessment is a challenging task in the warming climate. Thus, this study discusses factors that should be considered in developing drought indices in changing climate. Inconsistent drought assessment can be obtained, depending on the baseline period defined in developing drought indices. Therefore, the baseline period should represent the contemporary climate but should also correspond to long enough observations for stable parameter estimation. The importance of accurate potential evapotranspiration (PET) for drought indices becomes higher under a warming climate. Although the Penman-Monteith method yields accurate PET values, depending on the climate and vegetation cover, other suitable PET formulas, such as the Hargreaves method, with fewer hydrometeorological data can be used. Since a single drought index is not enough to properly monitor drought evolution, a method that can objectively combine multiple drought indices is required. Besides, quantifying anthropogenic impacts, which can add more uncertainty, on drought assessment is also important to adapt to the changing drought conditions and minimize human-induced drought. Drought is expected to occur more frequently with more severe, longer, and larger areal extent under global warming, since a more arid background, which climate change will provide, intensifies land-atmosphere feedback, leading to the desiccation of land and drying atmosphere. Thus, an accurate drought assessment, based on robust drought indices, is required.


Assuntos
Mudança Climática , Secas , Humanos , Monitoramento Ambiental , Aquecimento Global , Efeitos Antropogênicos
12.
J Org Chem ; 88(24): 16934-16948, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-38008916

RESUMO

The synthesis of 1,3-benzoselenazoles was achieved by the reaction of corresponding bis[3-amino-N-(p-tolyl)benzamide-2-yl] diselenide, bis[3-amino-N-(4-methoxyphenyl)benzamide-2-yl] diselenide, and bis[3-amino-N-(4-(dimethylamino)phenyl) benzamide-2-yl] diselenide with aryl aldehydes. The 1,3-benzoselenazoles continued to exist as planar molecules due to the presence of secondary Se···O interactions as revealed by the single-crystal X-ray analysis. The presence of secondary Se···O interactions in 1,3-benzoselenazoles was confirmed using natural bond orbital (NBO) and atoms in molecules (AIM) calculations. Nucleus-independent chemical shift (NICS) values suggested the presence of aromatic character in a five-membered benzoselenazole heterocyclic ring. The glutathione peroxidase (GPx)-like antioxidant activity of all 1,3-benzoselenazoles was assessed using a thiophenol assay, exhibiting greater antioxidant activity than Ph2Se2 used as a reference. The most active catalyst carrying a strong electron-donating group (-NMe2) at the ortho-position to the benzoselenazole ring was further investigated at different concentrations of thiophenol, H2O2, and 1,3-benzoselenazoles as catalyst for determining their catalytic parameters. Moreover, the potential applications of all 1,3-benzoselenazoles against pancreatic lipase (PL) have been identified using in silico interactions between the active sites of the 1LPB protein as evaluated using a molecular docking study.


Assuntos
Antioxidantes , Peróxido de Hidrogênio , Antioxidantes/farmacologia , Simulação de Acoplamento Molecular , Glutationa Peroxidase/química , Lipase , Benzamidas
13.
J Environ Manage ; 346: 118948, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37717396

RESUMO

The inundation process of floodplain wetlands plays a crucial role in maintaining the balance of river ecosystems, which are highly sensitive to hydrological alteration. Nevertheless, the specific mechanisms through which these hydrological changes affect the inundation patterns of floodplain wetlands are still unclear. This study aimed to investigate the impact mechanism of cascade hydropower development on the inundation process of floodplain wetlands. Multitemporal remote sensing datasets and long-term hydrometeorological data series were utilized in this study. By employing the water appearance frequency (WAF) index, wetland hydrological stability assessment, and wavelet analysis, the inundation changes in floodplain wetlands and the underlying hydrological driving mechanisms were examined. The results revealed significant alterations in the inundation frequency of floodplain wetlands due to the construction of upstream dams. Specifically, the construction of the Danjiangkou and Wangfuzhou dams led to an increase in the total inundated area of Part A (16.09 km2) and Part B (76.93 km2), respectively. Conversely, the moderate frequency inundation zone in Part C decreased (26.7 km2) after the construction of the Cuijiaying Dam. The typical floodplain wetland 7 shifted from high to low (8.94 km2) stability after the construction of the Cuijiaying Dam. Furthermore, the cascade hydropower dam construction resulted in increased fluctuations in downstream water discharge. This study provides an effective approach to understanding the impact of cascade hydropower dams on the inundation process of floodplain wetlands.

14.
Sci Total Environ ; 905: 167181, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37758134

RESUMO

Freshwater availability in coastal areas depends on the withdrawal from tidal rivers. It is severely threatened by saltwater intrusion, especially in the dry season. Freshwater availability is associated closely with natural factors and human activities. Limited research has investigated how freshwater availability is influenced by saltwater intrusion, streamflow, projects, etc., and how the water supply security downstream is affected by the abovementioned factors. To fill these gaps, this paper presents a new framework, i.e., water supply regulation by avoiding saltwater withdrawal (RASW). The framework is based on data on streamflow, tide, wind, the salinity of withdrawal stations, capacities of withdrawal projects and reservoirs, and water demand, which holistically develops relationships among saltwater intrusion, upstream streamflow, and water supply. The RASW contains three phases, i.e., estuary salinity-exceedance simulation, upstream streamflow distribution design, and local water supply security analysis. The proposed intellectual framework and methodology have been tested on the water supply for Zhuhai-Macao of the Guangdong-Hong Kong-Macao Great Bay Area, South China. Results demonstrated that the meta-Gaussian copula efficiently simulated the six-dimensional monthly streamflow distribution and was appropriate for streamflow distribution scenario design. Water supply security benefited greatly from the joint river-reservoir regulation mode. Nevertheless, the water supply security was threatened in the extreme scenarios when the extremely low streamflow distribution happened in the late period or lasted for an extended period. The proposed framework facilitates integrated decision-making for water supply security in coastal areas. Utilizing the streamflow distribution as a management tool and controlling them to avoid extremely low streamflow and adjust their occurrence time can alleviate water supply pressure. Moreover, the capacities of local regulating facilities should be designed with full consideration.

15.
Plants (Basel) ; 12(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37765405

RESUMO

Pomegranate (Punica granatum L.) is a fruit tree that is globally distributed, especially in warm areas with low annual rainfall and limited water availability. This species exemplifies the critical role of water in agriculture and the need for efficient irrigation practices due to its characteristics, cultivation requirements, and geographic diffusion. In this study, we investigated the effects of drip irrigation and mulching on the vegetative growth, yield, and fruit quality attributes of pomegranate. The experiment involved three irrigation regimes (100% of evapotranspiration, 80%, and 60%) and three mulching treatments (no mulch, plastic mulch, and organic mulch) in a factorial combination. Both irrigation and mulching had significant positive influences on the yield and fruit quality attributes. Specifically, deficit irrigation strategies showed a negative impact on the fruit yield per tree, with a greater effect observed as the severity of the irrigation deficit increased. Mulching, on the other hand, led to a significant increase in the fruit yield, primarily attributed to an increase in fruit size. Furthermore, the analysis indicated that irrigation and mulching treatments had distinct effects on fruit traits such as the fruit length, width, volume, and rind thickness. Interestingly, the study highlighted that the effects of irrigation and mulching on fruit quality attributes were mostly independent of each other, suggesting an additive influence rather than an interaction between the two factors. These findings underscore the importance of considering irrigation and mulching practices for optimizing fruit quality in pomegranate cultivation, particularly in semi-arid regions. The results contribute valuable insights for farmers and researchers seeking to enhance fruit production and quality.

16.
Sci Total Environ ; 902: 166361, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595901

RESUMO

In the context of current global climate change, accurate drought prediction is crucial for water resources management and agricultural production. Although traditional drought forecasting methods largely rely on historical climatic data, these methods cannot fully consider the long-term effects of factors, such as climate change, and the evaluation of prediction results is limited. Therefore, this study proposed a drought prediction and evaluation framework based on Long Short-Term Memory (LSTM), integrating multi-source factors to significantly enhance the accuracy and reliability of drought prediction models. This framework applied two distinct forecasting schemes. The first scheme utilized ten diverse factors, including precipitation, evaporation, bare soil percentage area coverage, percentage crop cover, leaf area index, runoff, surface runoff, soil moisture, temperature, and total vegetated percentage cover, to predict future precipitation and evaporation, which was then used to calculate the Standardized Precipitation-Evaporation Index (SPEI) to evaluate drought characteristics. The second scheme directly used these ten factors and historical SPEI to predict future SPEI, further assessing future drought characteristics. By comparing the drought prediction results of the two schemes in terms of data statistics, drought characteristics, and spatial patterns, it was found that the LSTM model significantly improved accuracy when handling high-dimensional complex data and predicting key factors such as precipitation, evaporation, temperature, and soil moisture. The first scheme was more accurate when predicting severe and extreme droughts, whereas the second scheme was more sensitive to predicting moderate and mild droughts and exhibited higher stability and regularity in predicting the spatial variability of drought. In summary, LSTM has made significant improvements in the accuracy, stability, and reliability of drought prediction, providing stronger support for practical applications, such as agriculture and water resources management, and offering a new research tool for further climate change research.

17.
Gastroenterology ; 165(4): 999-1015, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37263302

RESUMO

BACKGROUND & AIMS: Although transient bacteremia is common during dental and endoscopic procedures, infections developing during sterile diseases like acute pancreatitis (AP) can have grave consequences. We examined how impaired bacterial clearance may cause this transition. METHODS: Blood samples from patients with AP, normal controls, and rodents with pancreatitis or those administered different nonesterified fatty acids (NEFAs) were analyzed for albumin-unbound NEFAs, microbiome, and inflammatory cell injury. Macrophage uptake of unbound NEFAs using a novel coumarin tracer were done and the downstream effects-NEFA-membrane phospholipid (phosphatidylcholine) interactions-were studied on isothermal titration calorimetry. RESULTS: Patients with infected AP had higher circulating unsaturated NEFAs; unbound NEFAs, including linoleic acid (LA) and oleic acid (OA); higher bacterial 16S DNA; mitochondrial DNA; altered ß-diversity; enrichment in Pseudomonadales; and increased annexin V-positive myeloid (CD14) and CD3-positive T cells on admission. These, and increased circulating dead inflammatory cells, were also noted in rodents with unbound, unsaturated NEFAs. Isothermal titration calorimetry showed progressively stronger unbound LA interactions with aqueous media, phosphatidylcholine, cardiolipin, and albumin. Unbound NEFAs were taken into protein-free membranes, cells, and mitochondria, inducing voltage-dependent anion channel oligomerization, reducing ATP, and impairing phagocytosis. These were reversed by albumin. In vivo, unbound LA and OA increased bacterial loads and impaired phagocytosis, causing infection. LA and OA were more potent for these amphipathic interactions than the hydrophobic palmitic acid. CONCLUSIONS: Release of stored LA and OA can increase their circulating unbound levels and cause amphipathic liponecrosis of immune cells via uptake by membrane phospholipids. This impairs bacterial clearance and causes infection during sterile inflammation.


Assuntos
Pancreatite , Humanos , Doença Aguda , Ácidos Graxos não Esterificados , Ácido Oleico , Inflamação , Albuminas , Fosfatidilcolinas
18.
Sci Total Environ ; 880: 163342, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030391

RESUMO

Farmland ecosystems (FEs) constitute the most important source of food production, and water is one of the most important factors influencing FEs. The amount of water can affect the yield and thus the economic efficiency. Water migration can generate environmental effects through the migration of fertilizers. Interlinkages and constraints exist between the water, economy and environment, which require synergistic regulation. Meteorological elements influence the reference crop uptake amount and thus the water cycle processes and are key drivers of regulation at the water-economy-environment nexus. However, the weather-driven, synergistic water-economy-environment regulation of FEs has not been sufficiently researched. As such, this paper employed a dynamic Bayesian prediction of the reference evapotranspiration (ETo) and a quantitative characterization of the total nitrogen (TN) and total phosphorus (TP) contents in agricultural crops and soils via field monitoring and indoor experimental analysis. Consequently, multiobjective optimization modeling was conducted to weigh the mutual trade-offs and constraints between water, the economy and the environment. The proposed method was verified via an example involving the modern agricultural high-tech demonstration park in Harbin, Heilongjiang Province, China. The results indicated that (1) the effect of meteorological factors gradually decreased over time, but the prediction results were very accurate, and the higher the delay order of the dynamic Bayesian network (DBN) was, the more accurate the predictions; (2) ETo was significantly driven by meteorological elements, and the most important meteorological factor influencing ETo throughout the year was average temperature. When the average temperature was reduced by 10.0 %, ETo was reduced by 1.4 %, the required amount of irrigation water was reduced by 4.9 %, and the economic benefits of a single cube of water increased by 6.3 %; (3) resource-economy-environment multidimensional synergy enabled a 12.8 % reduction in agricultural ecosystem pollutant emissions, while the economic benefits per unit of water increased by 8.2 % and the system synergy increased by 23.2 %.

19.
Nature ; 615(7950): 87-93, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859582

RESUMO

Water resources sustainability in High Mountain Asia (HMA) surrounding the Tibetan Plateau (TP)-known as Asia's water tower-has triggered widespread concerns because HMA protects millions of people against water stress1,2. However, the mechanisms behind the heterogeneous trends observed in terrestrial water storage (TWS) over the TP remain poorly understood. Here we use a Lagrangian particle dispersion model and satellite observations to attribute about 1 Gt of monthly TWS decline in the southern TP during 2003-2016 to westerlies-carried deficit in precipitation minus evaporation (PME) from the southeast North Atlantic. We further show that HMA blocks the propagation of PME deficit into the central TP, causing a monthly TWS increase by about 0.5 Gt. Furthermore, warming-induced snow and glacial melt as well as drying-induced TWS depletion in HMA weaken the blocking of HMA's mountains, causing persistent northward expansion of the TP's TWS deficit since 2009. Future projections under two emissions scenarios verified by satellite observations during 2020-2021 indicate that, by the end of the twenty-first century, up to 84% (for scenario SSP245) and 97% (for scenario SSP585) of the TP could be afflicted by TWS deficits. Our findings indicate a trajectory towards unsustainable water systems in HMA that could exacerbate downstream water stress.


Assuntos
Altitude , Mudança Climática , Dessecação , Previsões , Abastecimento de Água , Humanos , Ásia , Mudança Climática/estatística & dados numéricos , Abastecimento de Água/estatística & dados numéricos , Tibet , Congelamento , Neve , Imagens de Satélites , Chuva , Oceano Atlântico , Camada de Gelo , Conservação dos Recursos Hídricos
20.
J Org Chem ; 88(7): 4273-4285, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36930142

RESUMO

Copper-catalyzed direct selenation of substituted 2-bromo-N-phenylbenzamide substrates with elemental selenium powder provided a series of methoxy-substituted isoselenazolones via the C-Se and Se-N bond formations. Phenolic substituted isoselenazolones have been obtained by O-demethylation of the corresponding methoxy-substituted analogues using boron tribromide. Some isoselenazolones have been structurally characterized by X-ray single-crystal analysis. The glutathione peroxidase (GPx)-like antioxidant activity of isoselenazolones has been evaluated both in thiophenol and coupled-reductase assays. All isoselenazolones showed good GPx-like activities in the coupled-reductase assay. The ferric-reducing antioxidant power of phenolic antioxidants has also been evaluated. The best phenolic antioxidants were found to be good ferric-reducing antioxidant power agents. The single electron transfer, hydrogen atom transfer, and proton-coupled electron transfer mechanisms for the antioxidant properties of all catalysts have been supported by density functional theory calculations. The catalytic cycle was proposed for one of the phenolic isoselenazolones involving diselenide, selenenyl sulfide, selenol, and selenenic acid as intermediates using 77Se{1H} NMR spectroscopy.

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