Summary
Rice grain filling rate contributes largely to grain productivity and accumulation of nutrients. MicroRNAs (miRNAs) are key regulators of development and physiology in plants and become a ...novel key target for engineering grain size and crop yield. However, there is little studies, so far, showing the miRNA regulation of grain filling and rice yield, in consequence. Here, we show that suppressed expression of rice miR1432 (STTM1432) significantly improves grain weight by enhancing grain filling rate and leads to an increase in overall grain yield up to 17.14% in a field trial. Molecular analysis identified rice Acyl‐CoA thioesterase (OsACOT), which is conserved with ACOT13 in other species, as a major target of miR1432 by cleavage. Moreover, overexpression of miR1432‐resistant form of OsACOT (OXmACOT) resembled the STTM1432 plants, that is, a large margin of an increase in grain weight up to 46.69% through improving the grain filling rate. Further study indicated that OsACOT was involved in biosynthesis of medium‐chain fatty acids. In addition, RNA‐seq based transcriptomic analyses of transgenic plants with altered expression of miR1432 demonstrated that downstream genes of miR1432‐regulated network are involved in fatty acid metabolism and phytohormones biosynthesis and also overlap with the enrichment analysis of co‐expressed genes of OsACOT, which is consistent with the increased levels of auxin and abscisic acid in STTM1432 and OXmACOT plants. Overall, miR1432‐OsACOT module plays an important role in grain filling in rice, illustrating its capacity for engineering yield improvement in crops.
Compared with fully face‐to‐face or online learning environments, implementation of hybrid learning spaces is costly given the spaces making all learning options available for learners. Therefore, ...decisions on investments in hybrid learning are critical for institutions. Satisfaction and experience of learners is one of the important indicators for assessing the cost‐effectiveness of learning space implementation; thus, predictions of learners' satisfaction and experience can inform institutions' decision making on learning space investments. Moreover, learning competences are found correlated with learners' satisfaction and experience in general and e‐learning settings. Therefore, the present study aimed at exploring predictive learning competences for hybrid learners' experience and satisfaction. A hybrid learning space was built upon a proposed model at Shanghai Open University. 211 students’ learning competences and their satisfaction and experience in the hybrid learning space were examined. The results showed that except cognitive engagement competence, most predictive competences were not significantly associated with hybrid learners' satisfaction and experience. The findings indicated that since hybrid learning keeps all options available, to experience satisfying learning, students need not have certain competences but cognitive engagement competence, which is correlated with learners' cognitive ability to figure out the right mix of learning options.
Nitrogen is one of the important factors for high yield of rice. Apart from high yield, high quality has become the current urgent demand for rice production. Grain-filling stage is crucial for rice ...yield and quality formation. However, the effect of nitrogen on grain-filling characteristics and the relationship of grain-filling characteristics and rice quality of mid-season indica rice were still unclear. A field experiment was carried out to ascertain the critical grain-filling characteristics that contribute to rice milling quality, appearance quality and cooking and eating quality under nitrogen applications. The results showed that nitrogen applications prolonged the duration of superior and inferior grain filling. The mean grain-filling rate (Gmean) and the maximum grain-filling rate (Gmax) of the inferior grains were positively correlated with chalky kernel rate, chalkiness, and amylose content. The time reaching the maximum grain-filling rate (Tmax G) of the inferior grains was positively correlated with brown rice rate, milled rice rate, and head milled rice rate. Chalky kernel rate and chalkiness were negatively correlated with peak paste viscosity and breakdown viscosity. Less amylose content and more crude protein content were detected in nitrogen application of Liangyoupei 9 and Y Liangyou 2 both in 2016 and 2017. According to the correlation analysis, better cooking and eating quality of Y Liangyou 2 which had less amylose content might result from its higher Gmax and Gmean of inferior grain than that of Liangyoupei 9 in the treatments of nitrogen application. These results indicated that the prolonging grain-filling duration and increasing grain weight at the maximum grain-filling rate of inferior grains contributed to the improvement of milling quality, appearance quality, and cooking and eating quality of mid-season indica rice under appropriate nitrogen applications.
Background
The impact of hepatic resection type on long-term oncological prognosis of patients with early-stage hepatocellular carcinoma (HCC) has not been systematically investigated. We sought to ...determine risk factors, recurrence patterns, and survival outcomes after anatomical resection (AR) versus non-anatomical resection (NAR) for early-stage HCC.
Methods
From a prospectively collected multicenter database, consecutive patients undergoing curative hepatectomy for early-stage HCC were identified. Recurrence patterns, overall survival (OS), recurrence-free survival (RFS), and risk factors were investigated in patients undergoing AR versus NAR using propensity score matching (PSM), subgroup analysis, and COX regression analysis.
Results
A total of 3585 patients with early-stage HCC were enrolled, including 1287 and 2298 in the AR and NAR groups, respectively. After PSM, the OS and RFS of patients in the AR group were 58.8% and 42.7%, which were higher than those in the NAR group (52.2% and 30.6%, both
p
< 0.01). The benefits of AR were consistent across most subgroup analyses of OS and RFS. Multivariable COX regression analysis showed that AR was independently associated with better OS and RFS. Notably, although recurrence patterns were comparable, the risk factors for recurrence were not identical for AR versus NAR. Microvascular invasion and narrow resection margin were only associated with a higher recurrence rate after NAR.
Conclusions
This study demonstrated that AR decreases the risk of tumor recurrence and improves OS and RFS in patients with early-stage HCC. AR should be adopted as long as such a surgical maneuver is feasible for initial treatment of early-stage HCC.
Graphical abstract
Zingiber cassumunar is an important plant used in traditional medicine and as a natural mosquito repellent. However, the compounds responsible for the repellent activity of the plant are still ...unknown. The aim of the study is to identify the components of Z. cassumunar essential oil that show repellent activity against Aedes albopictus. We also evaluated the larvicidal and adulticidal activities of Z. cassumunar essential oil against Ae. albopictus. In-cage mosquito repellent experiments showed that Z. cassumunar essential oil possessed moderate repellent activity with a minimum effective dose (MED) of 0.16 ± 0.01 mg/cm2, compared to reference standard N,N-diethyl-3-methylbenzamide (DEET, 0.03 ± 0.01 mg/cm2). Bioassay-guided fractionation identified the major active compound of Z. cassumunar essential oil as (−)-terpinen-4-ol (1) (MED: 0.19 ± 0 mg/cm2). We also found that Z. cassumunar essential oil showed moderate larvicidal activity against first instar larvae of Ae. albopictus with a LC50 (50% lethal concentration) of 44.9 μg/L after 24 h. Fumigation bioassays showed that Z. cassumunar essential oil exhibits moderate adulticidal activity against Ae. albopictus with a LC50 of 5.44%, while (−)-terpinen-4-ol showed significant adulticidal activity with a LC50 of 2.10% after 24 h. This study verifies that the Z. cassumunar essential oil has mosquito repellent activity, and that (−)-terpinen-4-ol is mainly responsible for this activity. Furthermore, this study provides scientific support for the folk usage of Z. cassumunar essential oil as mosquito repellent and indicates that Z. cassumunar essential oil and (−)-terpinen-4-ol can be used as plant-derived repellents and insecticides for mosquito control.
This study examined the effects of comparison and game-challenge strategies on sixth graders' learning achievement of algebra variable, learning attitude towards algebra variable learning, and ...meta-cognitive awareness of algebra variable learning. A 2 × 2 factorial design was used, and 86 students were invited to participate in the experimental instruction and assigned to four groups: comparison with game-challenge, comparison, game-challenge, and control. The results showed that (1) a significant interaction effect was found on students' learning achievement of algebra variable: the comparison with game-challenge group performed significantly better than the comparison group and the game-challenge group respectively; (2) a significant interaction effect was found on students' learning attitude towards algebra variable: the comparison with game-challenge group responded significantly more positively than the comparison group and the game-challenge group respectively; and (3) a significant interaction effect was found on students' meta-cognitive awareness of algebra variable learning: the comparison with game-challenge group reported significantly higher scores than the comparison group and the game-challenge group respectively.
This study examined effects of gamified comparison on sixth graders' performance of algebra word problem solving and attitude toward algebra learning. Seventy-two sixth graders were invited to ...participate in a four-week experimental instruction and assigned to three groups: gamified comparison, comparison, and control. The results showed (1) a significant effect on solving similar problems: the gamified comparison group performed significantly better than the comparison group and the control group respectively, and the comparison group performed significantly better than the control group; (2) a significant effect on solving transfer problems: the gamified comparison group gained significantly higher scores than the comparison group and the control group respectively, and the comparison group gained significantly higher scores than the control group; (3) a significant effect on students' learning attitude: while no significant differences found on students' confidence, the gamified comparison group made significantly more positive responses than the comparison group and the control group in terms of enjoyment, motivation, and perceived value. This study proposed a feasible combination of game rule and comparison strategy, as well as exploring implications for teachers' teaching design and students' gamified learning activities.
We carried out a pool culture experiment to determine the optimal water treatment depth in loam and clay soils during the late growth stage of super rice. Three controlled water depth treatments of ...0-5, 0-10 and 0-15 cm below the soil surface were established using alternate wetting and drying irrigation, and the soil water potential (0 to -25 kPa) was measured at 5, 10 and 15 cm. A 2-cm water layer was used as the control. We measured soil enzyme activities, root antioxidant enzyme activities, chlorophyll fluorescence parameters, and rice yield. The results showed that the 0-5-cm water depth treatment significantly increased root antioxidant enzyme activities in loam soil compared with the control, whereas soil enzyme activities, chlorophyll fluorescence parameters and yield did not differ from those of the control. The 0-10- and 0-15-cm water depth treatments also increased root antioxidant enzyme activities, whereas soil enzyme activities, chlorophyll fluorescence parameters and yield decreased. In clay soil, the soil enzyme activities, root antioxidant enzyme activities, chlorophyll fluorescence parameters, and yield did not change with the 0-5-cm water treatment, whereas the 0-10- and 0-15-cm water treatments improved these parameters. Therefore,the appropriate depths for soil water during the late growth period of rice with a 0 to -25 kPa water potential were 5 cm in loam and 15 cm in clay soil.
Superior grains determined by grain weight are not fully correlated with the flowering order in rice PENG Ting, L Qiang, ZHAO Ya-fan, SUN Hong-zheng, HAN Ying-chun, DU Yan-xiu, ZHANG Jing, LI Jun-zhou, WANG Lin-lin, ZHAO Quan-zhi (State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, P.R.China)
Journal of Integrative Agriculture,
05/2015, Letnik:
14, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Rice panicles are composed of many branches with two types of extreme grains,the superior and the inferior.Traditionally,it has been well accepted that earlier flowers result in superior grains and ...late flowers generate inferior grains.However,these correlations have never been strictly examined in practice.In order to determine the accurate relationship between superior and inferior grains and the flowering order,we localized all the seeds in a panicle in four distinct rice species and systematically documented the rice flowering order,flower locations and the final grain weight for their relationships.Our results demonstrated that the grain weight is more heavily determined by the position of the seeds than by the flowering order.Despite earlier flowering has a positive correlation with the grain weight in general,grains from flowers blooming on the second day after anthesis generally gained the highest weight.This suggests earlier flowers may not result in superior grains.Therefore,we concluded that superior and inferior grains,commonly determined by grain weight,are not fully correlated with the flowering order in rice.Following the order of the grain weight,the superior grains are generally localized at the middle parts of the primary branches,whereas inferior grains were mainly on the last two secondary branches of the lower half part of the panicle.In addition,the weight of inferior grains were affected by spikelet thinning and spraying with exogenous plant growth regulators,indicating that physiological incompetence might be the major reason for the occurrence of the inferior grains.
This study examined the interaction effects of self-explanation and game-reward strategies on sixth graders' algebra variable learning achievement, learning attitude, and meta-cognitive awareness. A ...learning system was developed to support the learning activity, and a 2×2 quasi-experiment was conducted. Ninety-seven students were invited to participate in this experimental instruction and assigned to four groups: self-explanation with game-reward, self-explanation, game-reward, and control. The results showed that (1) a significant interaction effect was found on the students' learning achievement of algebra variable: the self-explanation with game-reward group performed significantly better than the self-explanation group, and both the game-reward group and self-explanation group scored significantly higher than the control group; (2) a significant interaction effect was found on the students' learning attitude toward algebra variable: the self-explanation with game-reward group reported significantly more positively than the self-explanation group, and the control group responded significantly more positive results than the self-explanation group; (3) no significant interaction effect was found on the students' meta-cognitive awareness of algebra variable learning: while the game-reward did not show a significantly positive effect, the self-explanation did.