A hybrid CNN-LSTM model for diagnosing rice nutrient levels at the rice panicle initiation stage

Nitrogen(N)and potassium(K)are two key mineral nutrient elements involved in rice growth.Accurate diagnosis of N and K status is very important for the rational application of fertilizers at a specific rice growth stage.Therefore,we propose a hybrid model for diagnosing rice nutrient levels at the early panicle initiation stage(EPIS),which combines a convolutional neural network(CNN)with an attention mechanism and a long short-term memory network(LSTM).The model was validated on a large set of sequential images collected by an unmanned aerial vehicle(UAV)from rice canopies at different growth stages during a two-year experiment.Compared with VGG16,AlexNet,GoogleNet,DenseNet,and inceptionV3,ResNet101 combined with LSTM obtained the highest average accuracy of 83.81%on the dataset of Huanghuazhan(HHZ,an indica cultivar).When tested on the datasets of HHZ and Xiushui 134(XS134,a japonica rice variety)in 2021,the ResNet101-LSTM model enhanced with the squeeze-and-excitation(SE)block achieved the highest accuracies of 85.38 and 88.38%,respectively.Through the cross-dataset method,the average accuracies on the HHZ and XS134 datasets tested in 2022 were 81.25 and 82.50%,respectively,showing a good generalization.Our proposed model works with the dynamic information of different rice growth stages and can efficiently diagnose different rice nutrient status levels at EPIS,which are helpful for making practical decisions regarding rational fertilization treatments at the panicle initiation stage.

Combining Transcriptomics and Metabolomics to Uncover the Effects of High-Energy Lithium-Ion Beam Irradiation on Capsicum annuum L.

Hot pepper(Capsicum annuum L.)is consumed as one of the oldest domesticated crops all over the world.Although mutation breeding using radiation has been performed in hot peppers,little is known about the comparative analysis of mutagenic effects at the molecular level by ion beam irradiation.To comprehend the response mechanism of hot pepper to the ion beam,we used a mutant with favorable economic characteristics induced by lithium-ion beam irradiation to investigate the biological effects.The results indicated that the lithium-ion beam had a positive effect on important agronomic traits,particularly yield unit,but had a negligible effect on the photosynthetic rate of hot pepper,with a specific influence on chlorophyll b rather than chlorophyll a.By RNA-Seq analysis,671 up-regulated and 376 down-regulated genes were identified as differentially expressed genes(DEGs)between irradiated and unirradiated hot pepper.Based on GO and KEGG network analysis,the auxin metabolic process was the common pathway in these two networks.A total of 118 potential reactive oxygen species(ROS)scavenging genes and 262 signal transduction genes were identified,suggesting a balance between antioxidant enzymes and enhanced ROS transduction.The amounts of 15 metabolite,involved in GABA pathways,secondary metabolism,carbohydrate metabolism,shikimate pathways,TCA cycles,nitrogen metabolism,glycerol metabolism and acetate pathways,were significantly changed in the ion beam irradiated sample.These results highlighted that the enriched pathways could play important roles in response to ion beam irradiation in hot pepper plants.In summary,these data provide valuable information for future research on ion beam irradiation and genomic studies in hot pepper.

膜龈手术中自体软组织替代物的研究进展

膜龈手术是多种矫正牙周软组织形态及结构异常的手术总称。传统膜龈手术中常使用带蒂或游离自体软组织移植治疗牙龈退缩和角化龈不足,但由于自体软组织移植瓣存在需要开辟第二术区、供区组织量有限和术后不适明显等不足,自体软组织替代材料的研究越来越受到关注。目前多种自体软组织替代材料已研发并应用于膜龈手术中,包括脱细胞真皮基质、异种胶原基质等。本文就现有几种软组织替代材料的特点和临床效果的研究进展做一综述,为临床膜龈手术中自体软组织替代物的应用提供参考。

Effect of various crop rotations on rice yield and nitrogen use efficiency in paddy–upland systems in southeastern China

To evaluate the effects of various rotation systems on rice grain yield and N use efficiency, a paddy–upland cropping experiment(2013–2016) was conducted in southeastern China. The experiment was designed using six different rice––winter crop rotations: rice–fallow(RF),rice–wheat(RW), rice–potato with rice straw mulch(RP), rice–green manure(Chinese milk vetch; RC–G), rice–oilseed rape(RO), and rice–green manure crop(oilseed rape with fresh straw incorporated into soil at flowering; RO–G) and three N rates, N0(0 kg N ha-1), N1(142.5 kg N ha-1), and N2(202.5 kg N ha-1). Average rice yields in the RF(5.93 t ha-1) rotation were significantly lower than those in the rotations with winter crops(7.20–7.48 t ha-1)under the N0 treatment, suggesting that incorporation of straw might be more effective for increasing soil N than winter fallow. The rice yield differences among the rotations varied by year with the N input. In general, the grain yields in the RP and RO–G rotations –were respectively 11.6–28.5% and 14.80–37.19% higher than those in the RF in plots with N applied. Increasing the N rate may have tended to minimize the average yield gap between the RF and the other rotations; the yield gaps were 18.55%, 4.14%, and 0.23% in N0, N1, and N2, respectively. However, the N recovery efficiency in the RF was significantly lower than that in other rotations, except for 2015 under both N1 and N2 rates, a finding that implies a large amount of chemical N loss. No significant differences in nitrogen agronomic efficiency(NAE) and physiological efficiency(NPE) were found between the rotations with legume(RC–G) and non–legume(RO and RW) winter crops, a result that may be due partly to straw incorporation. For this reason, we concluded that the return of straw could reduce differences in N use efficiency between rotations with and without legume crops. The degree of synchrony between the crop N demand and the N supply was evaluated by comparison of nitrogen balance degree(NBD) values. The NBD values in the RP and RW were significantly lower than those in the other rotations under both N1 and N2 rates. Thus,in view of the higher grain yield in the RP compared to the RW under the N1 rate, the RP rotation might be a promising practice with comparable grain yield and greater N use efficiency under reduced N input relative to the other rotations. The primary yield components of the RF and RP were identified as number of panicles m-2 and numbers of kernels panicle-1, respectively. The NAE and NPE were positively correlated with harvest index, possibly providing a useful indicator for evaluating N use efficiency.

Agronomic performance of drought-resistance rice cultivars grown under alternate wetting and drying irrigation management in southeast China

Compared to drought-susceptible rice cultivars(DSRs),drought-resistance rice cultivars(DRRs)could drastically reduce the amount of irrigation water input and simultaneously result in higher grain yield under water-saving irrigation conditions.However,the mechanisms underlying these properties are unclear.We investigated how improved agronomic traits contribute to higher yield and higher water use efficiency(WUE)in DRRs than in DSRs under alternate wetting and drying(AWD).Two DRRs and two DSRs were field-grown in 2015 and 2016 using two different irrigation regimes:continuous flooding(CF)and AWD.Under CF,no statistical differences in grain yield and WUE were observed between DRRs and DSRs.Irrigation water under the AWD regime was 275–349 mm,an amount 49.8%–56.2% of that(552–620 mm)applied under the CF regime.Compared to CF,AWD significantly decreased grain yield in both DRRs and DSRs,with a more significant reduction in DSRs,and WUE was increased in DRRs,but not in DSRs,by 9.9%–23.0% under AWD.Under AWD,DRRs showed a 20.2%–26.2% increase in grain yield and an 18.6%–24.5% increase in WUE compared to DSRs.Compared to DSRs,DRRs showed less redundant vegetative growth,greater sink capacity,higher grain filling efficiency,larger root biomass,and deeper root distribution under AWD.We conclude that these improved agronomic traits exert positive influences on WUE in DRRs under AWD.

Effects of increasing panicle-stage N on yield and N use efficiency of indica rice and its relationship with soil fertility

Because of the higher nitrogen(N)recovery efficiency(NRE)of panicle-stage fertilization compared with basal and tillering fertilization,increasing the proportion of N topdressing at the booting stage(panicleN)is recommended and commonly practiced in parts of China.To investigate the effects of increasing panicle-N on grain yield and N use efficiency(NUE)and the relationships of the increase and the rice cultivar and soil fertility status,we increased the percentage of panicle-N from 20%to 40%by correspondingly reducing the N amount applied only at the tillering stage in both high-and low-fertility blue clayey paddy fields in 2018 and 2019.Four indica cultivars with diverse panicle types were used,and their grain yield,dry matter accumulation,and NUE were compared.In high-fertility soil,increasing topdressing panicle-N from 20%to 40%reduced tillering ability and reduced the effective panicle numbers of the multi-and medium-panicle cultivars Huanghuazhan(HHZ),C Liangyouhuazhan(CHZ),and Tianyouhuazhan(THZ).These cultivars gave the greatest yield when 30%of N was supplied as panicle fertilizer,whereas the yield,NRE,N agronomic efficiency(NAE),and nitrogen physiological efficiency(NPE)of the heavy-panicle inbred cultivar Yangdao 6(YD6)continued to increase,resulting in improved dry matter accumulation and grain filling in the late growth stage.The yield,NAE,NRE,and NPE of YD6 peaked when the panicle-N constituted 40%.While in low-fertility soil,the multipanicle cultivar HHZ showed the greatest yield when 30%of fertilizer-N was applied once at the panicle initiation(PI)stage,while the medium-panicle cultivar CHZ showed the greatest yield when the panicle-N percentage was 40%.Our results suggest that the percentage of panicle-N fertilizer should not exceed 30%for multipanicle cultivars,while can be appropriately increased to 40%for heavy-panicle indica cultivars.The effect of increasing topdressing panicle-N on the yield of medium-panicle cultivars was related to soil fertility.The optimum panicle-N percentage was 30%in the high-fertility soil and 40%in the low-fertility soil.

Solar radiation-use characteristics of indica/japonica hybrid rice (Oryza sativa L.) in the late season in southeast China

New indica and japonica hybrid rice cultivars,such as the Yongyou series,provide farmers with very high yield potential.However,information on their canopy light capture and solar radiation use efficiency in the late season is limited.Field experiments were performed to compare the radiation-use parameters of four rice types:indica rice(IR),inbred japonica rice(IJR),hybrid japonica rice(HJR),and hybrid indica/japonica rice(HIJR),from 2016 to 2018 during the late season in Hangzhou,China.The grain yield,aboveground biomass,intercepted solar radiation(SI),and radiation-use efficiency(RUE)of the HIJR were on average respectively 13.4%–53.4%,14.3%–30.6%,7.6%–21.4%,and 8.2%–14.9%higher than those of the HJR,IJR,and IR.The leaf area index(LAI)of the HIJR was 18.2%–57.0%greater than that of the IJR and HJR at four growth stages,resulting in respectively 17.8%–38.5%and 10.7%–42.8%greater canopy light interception rates(LIR)and amount of intercepted solar radiation during the vegetative stage.The prolonged grain-filling stage also led to respectively 33.9%–52.6%and 30.5%–51.4%increases in amounts of incident and intercepted radiation for the HIJR relative to the IR during grain filling.These results indicate that the SI superiority of the HIJR was caused by canopy closure as rapid as that of the IR during the vegetative stage(greater LAI and canopy LIR during the growing season)and a grain-filling stage as long as that of the HJR.For grain-filling stage,differences in leaf Pn between HIJR,IR,and IJR were not significant,suggesting that the greater RUE of the HIJR(12.7%–52.8%higher)than that of the other rice types resulted from improved canopy architecture after flowering(FL).Principal components analysis(PCA)revealed that the superiority of the HIJR in terms of solar radiation use resulted from the greater canopy light capture capability of IR and the prolonged growth period(especially during grain filling)of japonica rice in the late growing season.

Transient induction of actin cytoskeletal remodeling associated with dedifferentiation,proliferation,and redifferentiation stimulates cardiac regeneration

The formation of new and functional cardiomyocytes requires a 3-step process:dedifferentiation,proliferation,and redifferentiation,but the critical genes required for efficient dedifferentiation,proliferation,and redifferentiation remain unknown.In our study,a circular trajectory using single-nucleus RNA sequencing of the pericentriolar material 1 positive(PCM1^(+))cardiomyocyte nuclei from hearts 1 and 3 days after surgery-induced myocardial infarction(MI)on postnatal Day 1 was reconstructed and demonstrated that actin remodeling contributed to the dedifferentiation,proliferation,and redifferentiation of cardiomyocytes after injury.We identified four top actin-remodeling regulators,namely Tmsb4x,Tmsb10,Dmd,and Ctnna3,which we collectively referred to as 2D2P.Transiently expressed changes of 2D2P,using a polycistronic non-integrating lentivirus driven by Tnnt2(cardiac-specific troponin T)promoters(Tnnt2-2D2P-NIL),efficiently induced transiently proliferative activation and actin remodeling in postnatal Day 7 cardiomyocytes and adult hearts.Furthermore,the intramyocardial delivery of Tnnt2-2D2P-NIL resulted in a sustained improvement in cardiac function without ventricular dilatation,thickened septum,or fatal arrhythmia for at least 4 months.In conclusion,this study highlights the importance of actin remodeling in cardiac regeneration and provides a foundation for new gene-cocktail-therapy approaches to improve cardiac repair and treat heart failure using a novel transient and cardiomyocyte-specific viral construct.

Gastrin attenuates sepsis-induced myocardial dysfunction by down-regulation of TLR4 expression in macrophages

Myocardial dysfunction is the most serious complication of sepsis.Sepsis-induced myocardial dysfunction(SMD)is often associated with gastrointestinal dysfunction,but its pathophysiological significance remains unclear.The present study found that patients with SMD had higher plasma gastrin concentrations than those without SMD.In mice,knockdown of the gastrin receptor,cholecystokinin B receptor(Cckbr),aggravated lipopolysaccharide(LPS)-induced cardiac dysfunction and increased inflammation in the heart,whereas the intravenous administration of gastrin ameliorated SMD and cardiac injury.Macrophage infiltration plays a significant role in SMD because depletion of macrophages by the intravenous injection of clodronate liposomes,48 h prior to LPS administration,alleviated LPSinduced cardiac injury in Cckbr-deficient mice.The intravenous injection of bone marrow macrophages(BMMs)overexpressing Cckbr reduced LPS-induced myocardial dysfunction.Furthermore,gastrin treatment inhibited toll-like receptor 4(TLR4)expression through the peroxisome proliferator-activated receptor a(PPAR-a)signaling pathway in BMMs.Thus,our findings provide insights into the mechanism of the protective role of gastrin/CCKBR in SMD,which could be used to develop new treatment modalities for SMD.

Cortisol safeguards oogenesis by promoting follicular cell survival

The role of glucocorticoids in oogenesis remains to be elucidated. cyp11c1 encodes the key enzyme involved in the synthesis of cortisol, the major glucocorticoid in teleosts. In our previous study, we mutated cyp11c1 in tilapia and analyzed its role in spermatogenesis. In this study, we analyzed its role in oogenesis. cyp11c1^(+/-)XX tilapia showed normal ovarian morphology but poor egg quality, as indicated by the mortality of embryos before 3 d post fertilization, which could be partially rescued by the supplement of exogenous cortisol to the mother fish. Transcriptome analyses revealed reduced expression of maternal genes in the eggs of the cyp11c1^(+/-)XX fish. The cyp11c1^(-/-)females showed impaired vitellogenesis and arrested oogenesis due to significantly decreased serum cortisol. Further analyses revealed decreased serum E2 level and expression of amh, an important regulator of follicular cell development, and increased follicular cell apoptosis in the ovaries of cyp11c1^(-/-)XX fish, which could be rescued by supplement of either exogenous cortisol or E2. Luciferase assays revealed a direct regulation of cortisol and E2 on amh transcription via GRs or ESRs. Taken together, our results demonstrate that cortisol safeguards oogenesis by promoting follicular cell survival probably via Amh signaling.

An Overview of Intelligent Wireless Communications Using Deep Reinforcement Learning

Future wireless communication networks tend to be intelligentized to accomplish the missions that cannot be preprogrammed.In the new intelligent communication systems,optimizing the network perfor-mance has become a challenge due to the ever-increasing complexity of the network environment.New theories and technologies for intelligent wireless communications have obtained widespread attention,among which deep reinforcement learning(DRL)is an excellent machine learning technology.DRL has great potential in enhancing the intelligence of wireless communication systems while overcoming the above challenge.This paper presents a review on applications of DRL in intelligent wireless com-munications with focuses on millimeter wave(mmWave),intelligent caching and unmanned aerial vehicle(UAV)scenarios.We first introduce the concepts and basic prin-ciples of single/multi-agent DRL techniques.Then,we review the related works where DRL algorithms are used to address emerging issues in wireless communications.These issues include mmWave communication,intelligent caching,UAV aided communication,and handover/access control in HetNets.Finally,critical challenges and future research directions of applying DRL in intelligent wireless communications are outlined.