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Sensitivity analysis (SA) intends to identify the key meteorological variables that affect the performance of reference crop evapotranspiration (ET0) models. It is of importance in assessing the variability of meteorological variables and ET0, especially in the face of increasing climate uncertainties. However, the surging of inconsistencies resulting from global changes in meteorological conditions due to climate change have impacted the ET0 model estimation in different regions, with detrimental effects on water resources and crop production. Therefore, efficient SA is necessary to evaluate the impact of changes in meteorological variables that influence ET0 model estimation. This mini review analyses the various SA methods applied in the field of ET0, based on a comprehensive and comparative analysis of existing SA methods from all around the world. The study discusses the advantages and disadvantages of each SA method, as well as the factors affecting the SA of ET0. The study also provides future prospects that may contribute to more solid and powerful analysis for ET0 model estimations and conclusions. HIGHLIGHTS The local and global sensitivity analysis for ET0 estimation were reviewed.; The categories, methods, and limitations for SA were examined.; The factors affecting the SA of ET0 were discussed.; The new possible research directions for SA in ET0 estimations are outlined.;

Potential evapotranspiration (PET) is an important parameter for the operation of irrigation projects and water resources management. The globally recognized PET estimation model, the FAO-56 Penman–Monteith (FAO-56 PM) model, had been criticized for its requirement of many detailed meteorological variables, but nevertheless has been accepted as the baseline model in many worldwide studies. The performances of different PET models can be found to be excellent for a specific location but may not be representative in other regions. The aim of this study is to select the most suitable PET model to estimate PET in Malaysia. Three radiation-based models and four temperature-based models were compared with the FAO-56 PM model at seven selected meteorological stations in Peninsular Malaysia. The mean bias error, relative error (Re) and normalized root-mean-square error (NRMSE) and coefficient of determination (R2) were used to evaluate the performances of the PET models. The Re values of Turc models were below 0.2 at all stations, while Priestly–Taylor, Thornthwaite, Thornthwaite-corrected and Blaney–Criddle models were above 0.2. The Makkink and Hargreaves–Samani models were below 0.2 at most of the stations. Thus, the Turc model was recommended as the best model to estimate PET in Peninsular Malaysia. HIGHLIGHTS This study applied various empirical potential evapotranspiration (PET) models to estimate the PET.; Radiation-based models and temperature-based models were compared with the FAO Penman–Monteith model.; MBE, Re, NRMSE and R2 were used to evaluate the performances of PET models.; The Turc model was found to give superior performance.; The outcomes can be used as a reference for water resources-related project design.;

Precise reference crop evapotranspiration (ET0) estimation plays a key role in agricultural fields as it aids in the proper operation and management of irrigation scheduling. However, reliable ET0 estimation poses a challenge when there is insufficient or incomplete long-term meteorological data at the East Coast Economic Region (ECER), Malaysia, where the economy is highly dependent on agricultural crop production. This study evaluated the performances of different standalone machine learning (ML) models, namely, the light gradient boosting machine (LGBM), decision forest regression (DFR), and artificial neural network (ANN) models using four different combinations of meteorological variables. The incorporation of solar radiation enhanced the accuracy of the standalone ML models, demonstrating the role of energetic factors in the evapotranspiration mechanism. Additionally, both the ANN and LGBM models showed overall satisfactory performances, and were thus recommended them as alternate models for ET0 estimation. This was owing to their good capability in capturing the non-linearity and interaction process among the meteorological variables. The outcomes of this study will be advantageous to farmers and policymakers in determining the actual crop water demands to maximize crop productivity in data-scarce tropical regions.

ABSTRACT Background: Alzheimer's disease (AD) is one of the most prevalent neurodegenerative disorders characterized by neuronal loss in the brain and cognitive impairment. AD is now considered to be the [...]

Objective: To investigate the effect of Kangshuailing Gao (KG) on benign prostatic hyperplasia (BPH) in rats and its action mechanisms., Methods: Fifty BPH model rats were randomized into five groups of equal number, BPH model control, finasteride control, and high-, medium- and low-dose KG, to be treated intragastrically with distilled water, finasteride solution at 0.52 mg/kg, and KG solution at 4.16, 2.08 and 1.04 g/kg respectively once a day for 30 days consecutively. Another 10 normal healthy rats were taken as blank controls. The rats were weighed once a week during the treatment. The wet weight and index of the prostate were obtained after treatment, followed by measurement of the contents of serum estradiol (E2) and dihydrotestosterone (DHT), testosterone (T) and hypoxia-inducible factor-1α (HIF-1α) in the prostatic tissue, and observation of histomorphological changes in the prostate under the light microscope., Results: Compared with the BPH model control group, high- and medium-dose KG significantly reduced the prostate wet weight (［0.84 ± 0.08］ vs ［0.69 ± 0.04］ and ［0.71 ± 0.07］ g, P < 0.01), the prostatic index (［0.28 ± 0.03］% vs ［0.20 ± 0.02］% and ［0.22 ± 0.03］%, P < 0.01), and the levels of T (［4.63 ± 1.25］ vs ［2.44 ± 0.47］ and ［2.91 ± 0.69］ ng/L, P < 0.01) and DHT (［154.44 ± 20.25］ vs ［88.23 ± 13.63］ and ［90.52 ± 16.44］ nmol/L, P < 0.01), but increased the level of E2 (［0.95 ± 0.24］ vs ［1.19 ± 0.14］ and ［1.20 ± 0.22］ nmol/L, P < 0.01) in the serum. High-dose KG remarkably reduced the overexpression of HIF-1α in the prostate tissue of the BPH model rats (P < 0.01) and alleviated such BPH-related symptoms as epithelium thinning, intraglandular secretion reduction, and interstitial substance decrease., Conclusions: Kangshuailing Gao acted effectively on BPH in the model rats by reducing the androgen level, balancing the estrogen/androgen ratio, and downregulating the expression of HIF-1α in the prostate tissue.