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Background and objectiveIt has been widely reported that Early neurological improvement (ENI) after rt-PA intravenous thrombolysis contributes to a good long-term prognosis in patients experiencing acute ischemic stroke (AIS). However, which clinical factors influence after intravenous administration of recombinant tissue-type plasminogen activator (IV-rt PA) in AIS patients ENI is still unclear. This study aimed to evaluate the impact of influencing factors on the benefit of ENI after intravenous thrombolysis neurological improvement after IV-rt PA.MethodsThe data of 73 patients with acute anterior circulation ischemic stroke who received intravenous thrombolysis with rt-PA in Chongqing University Jiangjin Hospital from January 2021 to July 2022 were retrospectively studied. According to the change rate of 24 h NISHH score, the research subjects were divided into the recovery group, the significant curative effect group, the curative effect group and the no curative effect group, the ENI after intravenous thrombolysis with rt-PA was defined as the improvement rate of National Institutes of Health Stroke Scale (NIHSS)score >46% at 24 h after IV-rt PA, and univariate factor analysis was used Clinical factors associated with ENI after intravenous thrombolysis.ResultsAccording to the 24-h NIHSS improvement rate of rt-PA intravenous thrombolysis in patients with acute anterior circulation ischemic stroke, 35 cases (47.95%) of the study population had ENI. There was no statistical difference between the improvement and non-improvement group in general demographic data, stroke TOAST classification, stroke risk factors (history of stroke, heart disease, hyperlipidemia, hypertension), and laboratory test data. There was a statistically significant difference in the random blood glucose levels between the two groups (p < 0.001, t = 3.511).ConclusionThe effect of rt-PA intravenous thrombolysis within the time window of patients with acute anterior circulation ischemic stroke is significant, but the ENI after thrombolysis is easily affected by the level of blood glucose; diabetes is the most important factor affecting the acute anterior circulation ischemic stroke patients Clinical factors of ENI after intravenous thrombolysis with rt-PA.

Soil texture affects rice nutrient uptake and yield formation by influencing soil structure, microbial activity, and soil nutrient supply capacity. Analyzing the relationship between soil texture, nutrient content, and rice agronomic traits is of great significance for precise and efficient fertilizer application. The tillage layer (0–20 cm) of 31 paddy fields in China's main rice-producing areas was collected to perform rice pot experiments, and soil texture characteristics, physicochemical properties, microbial-related indicators, and rice agronomic traits were measured and analyzed. The results showed that these soils could be classified into four types of soil texture: loamy sandy soil, sandy loam soil, silty loam soil, and silty soil. Analysis of variance showed that the available nitrogen (AN), available potassium (AK), and available phosphorus (AP) contents were the highest in silty loam, silty, and sandy loam soils, respectively, and silt loamy soil had the highest CEC. Principal component analysis (PCA) also showed that soil physicochemical properties can be distinguished to a certain extent according to soil texture types. For the relationship of soil texture parameters and soil physicochemical properties, soil organic matter (OM), total nitrogen (TN), AN, ammonium nitrogen (NH4+-N), and microbial carbon (MBC) contents were positively correlated with soil clay content, AK was positively correlated with silt content, and soil phosphorus status was significantly related to pH. Mantel's test revealed significant correlations between rice N, P, and K nutrient status, dry matter accumulation, and yield, and soil available nutrient content, MBC, pH, and soil texture parameters. Structural equation modeling (SEM) indicated that sand affected soil available nutrients by regulating pH, while clay can positively influence soil available nutrients by affecting soil organic matter mineralization and microbial activity, thus influencing nutrient absorption and yield formation in rice. Overall, in rice production, the silty and silty loam paddy soil with fine texture and higher clay content facilitates the mineralization of soil organic matter and the activity of soil microbes, resulting in more available soil nutrients, which benefits the rice absorption and accumulation of nutrients. Furthermore, a higher content of clay also promotes the distribution of dry matter to the panicle, thereby promoting rice yield formation. [ABSTRACT FROM AUTHOR]

Two rice cultivars (Xiushui 09 and Chunyou 84) were used to evaluate the effects of various soil oxygen (O2) conditions on soil nitrogen (N) transformation, absorption and accumulation in rice plants. The treatments were continuous flooding (CF), continuous flooding and aeration (CFA), and alternate wetting and drying (AWD). The results showed that the AWD and CFA treatments improved soil N transformation, rice growth, and N absorption and accumulation. Soil NO3– content, nitrification activity and ammonia-oxidising bacteria abundance, leaf area, nitrate reductase activity, and N absorption and accumulation in rice all increased in both cultivars. However, soil microbial biomass carbon and pH did not significantly change during the whole period of rice growth. Correlation analysis revealed a significant positive correlation between the nitrification activity and ammonia-oxidising bacteria abundance, and both of them significantly increased as the total N accumulation in rice increased. Our results indicated that improved soil O2 conditions led to changing soil N cycling and contributed to increases in N absorption and accumulation by rice in paddy fields. Keywords: ammonium-nitrogen content, nitrate-nitrogen content, nitrification activity, nitrate reductase activity, rhizosphere oxygen condition, ammonia-oxidising bacteria abundance, rice, nitrogen use efficiency

Deep placement of controlled-release fertilizer increases nitrogen (N) use efficiency in rice planting but is expensive. Few studies on direct-seeded rice have examined the effects of deep placement of conventional fertilizer. With prilled urea serving as N fertilizer, a two-year field experiment with two N rates (120 and 195 kg/hm2) and four basal N application treatments (B50, all fertilizer was broadcast with 50% as basal N; D50, D70 and D100 corresponded to 50%, 70% and 100% of N deeply placed as basal N, respectively) were conducted in direct-seeded rice in 2013 and 2014. Soil N distribution and plant N uptake were analyzed. The results showed that deep placement of basal N significantly increased total N concentrations in soil. Significantly greater soil N concentrations were observed in D100 compared with B50 at 0, 6 and 12 cm (lateral distance) from the fertilizer application point both at mid-tillering and heading stages. D100 presented the highest values of dry matter and N accumulation from seeding to mid-tillering stages, but it presented the lowest values from heading to maturity stages and the lowest grain yield for no sufficient N supply at the reproductive stage. The grain yield of D50 was the highest, however, no significant difference was observed in grain yield, N agronomic efficiency or N recovery efficiency between D70 and D50, or between D70 and B50, while D70 was more labor saving than D50 for only one topdressing was applied in D70 compared with twice in other treatments. The above results indicated that 70% of fertilizer-N deeply placed as a basal fertilizer and 30% of fertilizer-N topdressed as a panicle fertilizer constituted an ideal approach for direct-seeded rice. This recommendation was further verified through on-farm demonstration experiments in 2015, in which D70 produced in similar grain yields as B50 did. Keywords: Direct-seeded rice, Nitrogen fertilizer, Deep placement, Soil nitrogen distribution, Nitrogen utilization

Spikelet morphology of 250 specimens of 47 species of Schoeneae was examined using light microscopy and scanning electron microscopy. We confirmed that spikelet structure in Schoeneae is cymose with a sympodial 'rachilla.' Monopodial spikelets, as described by most current literature, were not found in Schoeneae. Prophylls are not always present in sympodial spikelets and cannot be used to determine whether a spikelet is sympodial or monopodial. Spikelets of Schoeneae develop acropetally, and the uppermost glume may or may not produce a flower. The last feature may be variable within species and within individual plants, so presence or absence of this flower is not an indication of sympodial or monopodial spikelet structure in Schoeneae. Relative position of flower, glume, and axis is a reliable criterion to judge whether spikelets are sympodial or monopodial. In some species of Schoenus and in Ptilothrix, formation of the arch-shaped base of the fertile glume relates to the shape of the inclined nodes on which the glume grows. This study highlights the need to reinvestigate spikelet structure in other tribes of Cyperaceae. Key words: Cyperaceae; monopodial; prophyll; rachilla; Rhynchosporeae; Schoeneae; spikelet; sympodial.