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Taking precipitation processes at the edge of subtropical high as target objects, three typical sub-regions including the southern foothills of Taihang Mountains, the eastern foothills of Funiu Mountains, and the eastern plains in Huanghuai Region are investigated, according to the topography and precipitation distribution characteristics. On this basis, using multi-source fusion precipitation data of National Meteorological Information Center, the precipitation refinement verification index, FSS (fractional skill score) and STFSS (spatial temporal fractional skill score) that adds the temporal neighborhood are used to evaluate the forecasting performance of the precipitation diurnal variation of CMA-MESO and CMA-SH9. The results show that the precipitation frequency and intensity by CMA-MESO in mountainous areas are smaller than observations, leading to significant underestimation, while results by CMA-SH9 are both stronger. The deviation of precipitation amount forecast of CMA-MESO in plain area mainly comes from the deviation of precipitation frequency. The precipitation intensity forecast by CMA-SH9 is stronger than observations in the southern foothills of Taihang Mountains, and the forecast precipitation frequency in the afternoon is significantly larger. For the early morning to morning period in the eastern foothills of Funiu Mountains, the frequency of precipitation by CMA-MESO is significantly lower than observations, while the diurnal variation of precipitation intensity is better than that of CMA-SH9. For the eastern plains, the overestimation of precipitation in early evening by CMA-SH9 mainly comes from the significantly larger precipitation intensity, while CMA-MESO significantly underestimates the frequency of precipitation in early evening and early morning. Based on the analysis of FSS, CMA-MESO is superior to CMA-SH9 in hourly precipitation forecast of more than 10 mm during afternoon to mid-night in the eastern foothills of Funiu Mountains and 0200 BT to 0400 BT in the night in the eastern plains, but the conclusion is opposite in the southern foothills of Taihang Mountains in the nighttime. STFSS can better evaluate the temporal and spatial uncertainty of hourly precipitation forecasts. Precipitation forecasts of CMA-SH9 in southern foothills of Taihang Mountains from the afternoon to the first half of the night significantly lag behind observations, but its spatial-deviation-scale and performance is better than CMA-MESO. The precipitation forecast of CMA-MESO from 0200 BT to 0800 BT in the eastern foothills of Funiu Mountains is significantly ahead of observations, and the advance time is more obvious in the eastern plains in the morning.

Humic acid, as a novel organic fertilizer, has the potential to improve soil fertility and the agronomic performance of crops. However, the efficacy of humic acid varied in previous studies and the mechanisms by which climatic conditions, soil properties, and fertilization regimes regulate it remain unclear. To test this, a comprehensive meta-analysis was conducted to evaluate the effects of humic acid across various environmental and agricultural conditions. The results showed that the humic acid amendment significantly increased the crop yield by 12%, nitrogen use efficiency by 27%, and nitrogen uptake by 17%, on average. Optimal effects were observed in regions with an annual precipitation > 300 mm and mean annual temperatures > 10 °C, and in soils with a moderate pH (6 < pH ≤ 8) or low total nitrogen. Its efficacy was attenuated in alkaline soils and high total nitrogen (≤1.5 g kg⁻1) or low soil organic carbon (<10 g kg⁻1) conditions. Cash crops and upland cereals showed a superior response compared to paddy rice, with optimal nitrogen application rates of 100–200 kg ha⁻1. This study quantifies humic acid's positive impacts on crop productivity and nitrogen utilization across various conditions, providing empirical evidence for optimizing its application in sustainable agricultural systems, potentially reducing excessive fertilizer use and its associated environmental pollution. [ABSTRACT FROM AUTHOR]

Rice (Oryza) is a genus in the Gramineae family, which has grown widely all over the world and is a staple food source for people's survival. The genetic information of rice has garnered significant attention in recent years, prompting numerous researchers to conduct extensive investigations in this field. But rice mitochondrial codon usage patterns have received little attention. The present study systematically analyzed the codon usage patterns and sources of variance in the mitochondrial genome sequences of five rice species by the CodonW and R software programs. Our results revealed that the GC content of codons in rice mitochondrial genome genes was determined to be 43.60%. Notably, the individual codon positions exhibited distinct GC contents: 48.00% for position 1, 42.65% for position 2, and 40.16% for position 3. These findings suggest the preference of the rice mitochondrial genome for codons ending in A or U. A weak codon bias was observed, with the effective number of codons (ENC) varying between 40.02 and 61.00, with an average value of 54.34. Subsequently, we identified 25 identical high-frequency codons in five rice mitochondrial genomes, with 11 codons ending in A and 12 codons ending in U. The regression lines in the neutrality plot exhibited slopes of less than 0.5 in five rice species, indicating a predominant role of natural selection, while mutation pressure remained relatively insignificant. In the PR2-plot analysis, most of the genes were located in the right half of the plot, indicating that the third base of the synonymous codon was preferred to end in G than C. Additionally, the ENC plot and ENC ratio analysis unveiled that codon preferences in the rice mitochondrial genome were predominantly influenced by natural selection rather than mutational pressure. The analysis of correspondence revealed distinct variations in the codon usage pattern across five rice mitochondrial genomes. Based on the RSCU values of species, a cluster tree was inconsistent with the mitochondrial genetic data, indicating that RSCU data could not be used as a basis for classification at the species level in the Oryza genus. These results will help decide the specific types of natural selection pressures influencing codon usage and improve the expression of exogenous genes in rice mitochondrial genomes by optimizing their codons. [ABSTRACT FROM AUTHOR]

The identification of the sex and sexual maturity of geoducks (Panopea japonica) is difficult because the outer shape of the males and females is indistinguishable. Moreover, depending on their size or age, the annual maturation cycle can vary. Vitellogenin (VTG) is a precursor protein of egg yolk. It has been studied as a biomarker for sex identification in geoducks. This article reports on the cDNA cloning of the P. japonica VTG gene for the VTG fragment. It was found to exhibit homology to known VTGs isolated from other marine molluscs, with more than 50% homology with oyster VTG. An enzyme-linked immunosorbent assay was developed to quantitatively detect the VTG level in geoducks. The VTG polyclonal antibody could recognize the extracted VTG in females, but the level of VTG in males was undetectable, providing a basis for an immunological assay for the identification of the sex and female maturational status of geoducks. Thus, this study established a simple and quantitative technique for the rapid identification of sex and/or maturation of females by using VTG in the hemolymph as a biomarker for the sampled geoducks without dissection or seriously injuring them.KEY WORDS: biomarker, ELISA, geoduck, sex identification, sexual maturity, vitellogenin, Panopea japonica, INTRODUCTIONThe genus Panopea is a large and long-lived shellfish known as geoduck. There are 10 described species of Panopea, most of which are known as geoducks. Some of these, such [...]

Based on the Dynamical–Statistical–Analog Ensemble Forecast model for Landfalling Typhoon Precipitation (DSAEF_LTP model), the optimal forecast scheme for the tropical cyclone (TC) accumulated precipitation over Hainan Island, China (DSAEF_LTP_HN) is established. To test the forecasting performance of DSAEF_LTP_HN, its forecasting results are compared with other numerical models. The average threat score (TS) of accumulated precipitation forecast by DSAEF_LTP_HN is compared with other numerical models over independent samples. The results show that for accumulated precipitation ≥ 100 mm, the TS produced by DSAEF_LTP_HN reaches 0.39, ranking first, followed by ECMWF (0.36). For accumulated precipitation ≥ 250 mm, the TS of DSAEF_LTP_HN (0.04) is second only to ECMWF (0.19). Further analysis reveals that the forecasting performance of DSAEF_LTP_HN for TC precipitation is closely related to the TC characteristics. The longer the TC impacts Hainan Island and the heavier the precipitation delivered to Hainan Island, the better the forecasting performance of DSAEF_LTP_HN is. DSAEF_LTP_HN can successfully capture the center of heavy precipitation. However, there is still a phenomenon of false forecasts for some TC heavy precipitation, which requires further improvement of the model in the future. [ABSTRACT FROM AUTHOR]