Two-photon live imaging of direct glia-to-neuron conversion in the mouse cortex

Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for n euro regeneration in the adult mammalian central ne rvous system.Howeve r,many questions remain regarding how a terminally differentiated glial cell can transform into a delicate neuron that forms part of the intricate brain circuitry.In addition,concerns have recently been raised around the absence of astrocyte-to-neuron conversion in astrocytic lineage-tra cing mice.In this study,we employed repetitive two-photon imaging to continuously capture the in situ astrocyte-to-neuron conversion process following ecto pic expression of the neural transcription factor NeuroD1 in both prolife rating reactive astrocytes and lineage-tra ced astrocytes in the mouse cortex.Time-lapse imaging over several wee ks revealed the ste p-by-step transition from a typical astrocyte with numero us short,tapered branches to a typical neuro n with a few long neurites and dynamic growth cones that actively explored the local environment.In addition,these lineage-converting cells were able to migrate ra dially or to ngentially to relocate to suitable positions.Furthermore,two-photon Ca2+imaging and patch-clamp recordings confirmed that the newly generated neuro ns exhibited synchronous calcium signals,repetitive action potentials,and spontaneous synaptic responses,suggesting that they had made functional synaptic connections within local neural circuits.In conclusion,we directly visualized the step-by-step lineage conversion process from astrocytes to functional neurons in vivo and unambiguously demonstrated that adult mammalian brains are highly plastic with respect to their potential for neuro regeneration and neural circuit reconstruction.

Low-Enthalpy and High-Entropy Polymer Electrolytes for Li-Metal Battery

lonic-conductive solid-state polymer electrolytes are promising for the development of advanced lithium batteries yet a deeper understanding of their underlying ion-transfer mechanism is needed to improve performance.Here we demonstrate the low-enthalpy and high-entropy(LEHE)electrolytes can intrinsically generate remarkably free ions and high mobility,enabling them to efficiently drive lithium-ion storage.The LEHE electrolytes are constructed on the basis of introducing CsPbl_(3)perovskite quantum dots(PQDs)to strengthen PEO@LiTFSI complexes.An extremely stable cycling>1000 h at 0.3 mA cm^(-2)can be delivered by LEHE electrolytes.Also,the as-developed Li|LEHE|LiFePO_(4)cell retains 92.3%of the initial capacity(160.7 mAh g^(-1))after 200 cycles.This cycling stability is ascribed to the suppressed charge concentration gradient leading to free lithium dendrites.It is realized by a dramatic increment in lithium-ion transference number(0.57 vs 0.19)and a significant decline in ion-transfer activation energy(0.14 eV vs 0.22 eV)for LEHE electrolytes comparing with PEO@LiTFSI counterpart.The CsPbl_(3)PQDs promote highly structural disorder by inhibiting crystallization and hence endow polymer electrolytes with low melting enthalpy and high structural entropy,which in turn facilitate long-term cycling stability and excellent rate-capability of lithium-metal batteries.

Isolation and bioactivity screening of soy isoflavones from soybean glycolipids identifies daidzin as a promising anti-inflammatory agent

Background:Soybean has long been utilized in the realm of traditional Chinese medicine.One of its extracts,soybean glycolipids,serves as a vital by-product of soybean oil refining,but its chemical composition and pharmacological potential have yet to be fully elucidated.Methods:In this study,the chemical components were isolated,and the inhibitory effects of these isolates were explored in different zebrafish inflammatory models by survival rate,Histological examination assay and quantitative Real-time PCR assay.The cytotoxicity of daidzin in RAW264.7 cells was evaluated by cell viability assay,and the effect of daidzin on the release of inflammatory cytokines in RAW264.7 cells was detected by enzyme linked immunosorbent assay(ELISA).Western blotting,immunofluorescence assay and alpha7 nicotinic acetylcholine receptors siRNA transfection assay were used to further explore the anti-inflammatory mechanism of daidzin.Results:Four compounds(verticilloside,soya-cerebroside I,soya-cerebroside II and daidzin)were firstly isolated from the soybean glycolipids,among which verticilloside and daidzin inhibited the lipopolysaccharide,CuSO4-and tail cut-stimulated zebrafish inflammation.Noticeably,daidzin exhibited anti-inflammatory activities by increasing the survival rate,alleviating the inflammatory cells infiltration,and down-regulating the expression of pro-inflammatory cytokines and nuclear factor kappa-B,NF-kappa-B inhibitor alpha,and signal transducer and activator of transcription3 in zebrafish.Moreover,daidzin decreased the secretion of IL-6 and TNF-α,inhibited the nuclear translocations of nuclear factor kappa-B p65 and p-signal transducer and activator of transcription3 as well as the NF-kappa-B inhibitor alpha phosphorylation at Ser32 in RAW 264.7 cells.More importantly,it elevated the expression level of alpha7 nicotinic acetylcholine receptors in both zebrafish and RAW 264.7 cells,and the inhibitory effect of daidzin was attenuated after the addition of alpha7 nicotinic acetylcholine receptors siRNA.Conclusion:Our study revealed that daidzin inhibited inflammation by activating the cholinergic anti-inflammatory pathway and further inhibiting the nuclear factor kappa-B and signal transducer and activator of transcription3 signaling.At the same time,it also promotes the recycling of crude soybean glycolipids and supports the potential use of daidzin as a functional food or natural dietary anti-inflammatory agent.

Ethanol extract of cassia seed alleviates metabolic dysfunction-associated steatotic liver disease by acting on multiple lipid metabolism-related pathways

Background and objective:In northern China's cold regions,the prevalence of metabolic dysfunction-associated steatotic liver disease(MASLD)exceeds 50%,significantly higher than the national and global rates.MASLD is an important risk factor for cardiovascular and cerebrovascular diseases,including coronary heart disease,stroke,and tumors,with no specific therapeutic drugs currently available.The ethanol extract of cassia seed(CSEE)has shown promise in lowering blood lipids and improving hepatic steatosis,but its mechanism in treating MASLD remains underexplored.This study aims to investigate the therapeutic effects and mechanisms of CSEE.Methods:MASLD models were established in male Wistar rats and golden hamsters using a high fat diet(HFD).CSEE(10,50,250 mg/kg)was administered via gavage for six weeks.Serum levels of total cholesterol(TC),triglyceride(TG),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),as well as liver TC and TG,were measured using biochemical kits.Histopathological changes in the liver were evaluated using Oil Red O staining,Hematoxylin-eosin(H&E)staining,and transmission electron microscopy(TEM).HepG2 cell viability was assessed using the cell counting kit-8(CCK8)and Calcein-AM/PI staining.Network pharmacology was used to analyze drug-disease targets,and western blotting was used to confirm these predictions.Results:CSEE treatment significantly reduced serum levels of TC,TG,LDL-C,ALT,and AST,and improved liver weight,liver index,and hepatic lipid deposition in rats and golden hamsters.In addition,CSEE alleviated free fatty acid(FFA)-induced lipid deposition in HepG2 cells.Molecular biology experiments demonstrated that CSEE increased the protein levels of p-AMPK,p-ACC,PPARα,CPT1A,PI3K P110 and p-AKT,while decreasing the protein levels of SREBP1,FASN,C/EBPα,and PPARγ,thus improving hepatic lipid metabolism and reducing lipid deposition.The beneficial effects of CSEE were reversed by small molecule inhibitors of the signaling pathways in vitro.Conclusion:CSEE improves liver lipid metabolism and reduces lipid droplet deposition in Wistar rats and golden hamsters with MASLD by activating hepatic AMPK,PPARα,and PI3K/AKT signaling pathways.

Study on the Impact of Post-Mastectomy Radiotherapy on Immediate Breast Reconstruction and Complications: A Meta-Analysis

Background and objective:Immediate breast reconstruction not only reduces the number of surgeries for patients after mastectomy but also decreases psychological and physical trauma,making it increasingly popular.However,there is currently no consensus on the integration of post-mastectomy radiotherapy(PMRT)with reconstruction techniques.This review evaluates the impact of PMRT on complications following immediate breast reconstruction,providing guidance for clinical treatment decisions.Methods:PubMed,Web of Science,Embase,and other databases were searched for studies published in the past 15 years on outcomes of implant-based breast reconstruction in the context of radiotherapy to identify articles for analysis.RevMan 5.4 software was used to analyze the risks of seroma,infection,wound dehiscence,flap necrosis,implant exposure,capsule contracture,and reconstruction failure.Results:A total of 1l relevant studies were included,comprising 6323 cases of immediate breast reconstruction.It was found that breasts receiving postoperative irradiation had a significantly increased risk of complications,with statistically significant differences in seroma(P=0.004),infection(P<0.00001),wound dehiscence(P=0.04),implant exposure(P<0.00001),capsule contracture(P<0.00001),and reconstruction failure(P<0.00001).There was no statistically significant difference in flap necrosis(P=0.88).Conclusion:The results indicate that postoperative radiotherapy significantly increases the risk of complications for patients undergoing immediate implant-based reconstruction.Preventive measures may be taken in advance with the assistance of healthcare providers if necessary.

Exendin-4 and linagliptin attenuate neuroinflammation in a mouse model of Parkinson's disease

Use of glucagon-like peptide-1 receptor agonist or dipeptidyl peptidase 4 inhibitor has been shown to lower the incidence of Parkinson's disease in patients with diabetes mellitus.Therefore,using these two treatments may help treat Parkinson's disease.To further investigate the mechanisms of action of these two compounds,we established a model of Parkinson's disease by treating mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and then subcutaneously injected them with the glucagon-like peptide-1 receptor agonist exendin-4 or the dipeptidyl peptidase 4 inhibitor linagliptin.We found that both exendin-4 and linagliptin reversed motor dysfunction,glial activation,and dopaminergic neuronal death in this model.In addition,both exendin-4 and linagliptin induced microglial polarization to the anti-inflammatory M2 phenotype and reduced pro-inflammatory cytokine secretion.Moreover,in vitro experiments showed that treatment with exendin-4 and linagliptin inhibited activation of the nucleotide-binding oligomerization domain-and leucine-rich-repeat-and pyrin-domaincontaining 3/caspase-1/interleukin-1βpathway and subsequent pyroptosis by decreasing the production of reactive oxygen species.These findings suggest that exendin-4 and linagliptin exert neuroprotective effects by attenuating neuroinflammation through regulation of microglial polarization and the nucleotidebinding oligomerization domain-and leucine-rich-repeat-and pyrin-domain-containing 3/caspase-1/interleukin-1βpathway in a mouse model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.Therefore,these two drugs may serve as novel anti-inflammatory treatments for Parkinson's disease.

Effect of cooked rice with added fructo-oligosaccharide on faecal microorganisms investigated by in vitro digestion and fermentation

In the present study,the effects of cooked rice(CR)with added fructo-oligosaccharide(FOS)on faecal flora were studied by a simulated in vitro digestion and fermentation method.The total carbohydrate content,p H,and s hort-chain fatty acids(SCFAs)were determined during in vitro digestion and fermentation.The change in the bacterial phase distribution after the fermentation was also analysed.The results showed that t he total carbohydrate content of the CR with added FOS(FCR)significantly decreased during the simulated digestion.Meanwhile,the p H of the FCR decreased and the SCFAs concentration increased significantly compared to those of the CR during the simulated fermentation.In addition,the FCR showed the advantage of promoting beneficial bacteria,such as Bifidobacterium and Lactobacillus,and inhibiting harmful bacteria,such as Bacteroides and Klebsiella compared to the CR.Therefore,the FOS as a prebiotic could be recommended to produce the high-quality healthy rice food.

Liraglutide Suppresses Myocardial Fibrosis Progression by Inhibiting the Smad Signaling Pathway

Objective Liraglutide is a commonly used hypoglycemic agent in clinical practice,and has been demonstrated to have protective effects against the development of cardiovascular disease.However,its potential role in myocardial fibrosis remains unexplored.The present study aims to assess the impact of liraglutide on the activation of cardiac fibroblasts.Methods Primary rat adult fibroblasts were isolated,cultured,and randomly allocated into 4 groups:control group,transforming growth factor beta1(TGFβ1)stimulation group,liraglutide group,and TGFβ1+liraglutide group.Fibroblast activation was induced by TGFβ1.Cell proliferation activity was assessed using the CKK-8 kit,and cellular activity was determined using the MTT kit.Reverse transcrition-quantitative polymerase chain reaction(RT-qPCR)was utilized to quantify the level of collagen transcription,immunofluorescence staining was performed to detect the expression level of type III collagen andα-smooth muscle protein(α-SMA),and immunoblotting was conducted to monitor alterations in signal pathways.Results The addition of 10,25,50 and 100 nmol/L of liraglutide did not induce any significant impact on the viability of fibroblasts(P>0.05).The rate of cellular proliferation was significantly higher in the TGFβl stimulation group than in the control group.However,the treatment with 50 and 100 nmol/L of liraglutide resulted in the reduction of TGFβl-induced cell proliferation(P<0.05).The RT-qPCR results revealed that the transcription levels of type I collagen,type III collagen,andα-SMA were significantly upregulated in the TGFβl stimulation group,when compared to the control group(P<0.05).However,the expression levels of these aforementioned factors significantly decreased in the TGFβl+liraglutide group(P<0.05).The immunofluorescence staining results revealed a significant increase in the expression levels of type III collagen andα-SMA in the TGFβl stimulation group,when compared to the control group(P<0.05).However,these expression levels significantly decreased in the TGFβl+liraglutide group,when compared to the TGFβl stimulation group(P<0.05).The Western blotting results revealed that the expression levels of phosphorylated smad2 and smad3 significantly increased in the TGFβl stimulation group,when compared to the control group(P<0.05),while these decreased in the TGFβl+liraglutide group(P<0.05).Conclusion Liraglutide inhibits myocardial fibrosis development by suppressing the smad signaling pathway,reducing the activation and secretion of cardiac fibroblasts.

Probabilistic time series forecasting with deep non-linear state space models

Probabilistic time series forecasting aims at estimating future probabilistic distributions based on given time series observations.It is a widespread challenge in various tasks,such as risk management and decision making.To investigate temporal patterns in time series data and predict subsequent probabilities,the state space model(SSM)provides a general framework.Variants of SSM achieve considerable success in many fields,such as engineering and statistics.However,since underlying processes in real-world scenarios are usually unknown and complicated,actual time series observations are always irregular and noisy.Therefore,it is very difficult to determinate an SSM for classical statistical approaches.In this paper,a general time series forecasting framework,called Deep Nonlinear State Space Model(DNLSSM),is proposed to predict the probabilistic distribution based on estimated underlying unknown processes from historical time series data.We fuse deep neural networks and statistical methods to iteratively estimate states and network parameters and thus exploit intricate temporal patterns of time series data.In particular,the unscented Kalman filter(UKF)is adopted to calculate marginal likelihoods and update distributions recursively for non-linear functions.After that,a non-linear Joseph form covariance update is developed to ensure that calculated covariance matrices in UKF updates are symmetric and positive definitive.Therefore,the authors enhance the tolerance of UKF to round-off errors and manage to combine UKF and deep neural networks.In this manner,the DNLSSM effectively models non-linear correlations between observed time series data and underlying dynamic processes.Experiments in both synthetic and real-world datasets demonstrate that the DNLSSM consistently improves the accuracy of probability forecasts compared to the baseline methods.

最优尺寸参数对涡流管能量分离效应影响的研究

为确定出涡流管各因素的主次顺序,找出最优的参数组合,提出正交试验设计和极差分析法,找到涡流管能量分离效应的最优化尺寸参数。实验设定涡流管进气温度为26℃,环境温度为27.1℃,结果表明,4个尺寸参数对涡流管能量分离影响排序为:长径比>喷嘴数目>冷端直径>进气压力,每个参数的最优值各为长径比为25.0、喷嘴个数为6、冷端直径为5 mm、进气压力为0.8 MPa,并通过对试验结果的验证,发现涡流管的冷热端出口温差为95.2℃。根据正交试验设计方案找出了涡流管各部件的最优尺寸参数。

肝硬化失代偿期患者皮肤感染致脓毒性休克的护理

总结1例肝硬化失代偿期患者皮肤软组织非特异性感染致脓毒性休克的护理体会。护理要点:以目标平均动脉压为导向,实施液体复苏;加强全程营养管理,加速创面修复;肝硬化失代偿期间,出血与血栓防范护理;加强院感管理,预防院内感染。经过45 d个性化的治疗和护理,双下肢植皮存活,无院内感染发生,患者康复出院。

肺康复综合治疗对慢性阻塞性肺疾病急性加重期患者肺功能及运动能力的影响研究

目的:探讨肺康复综合治疗对慢性阻塞性肺疾病急性加重期(AECOPD)患者肺功能及运动能力的影响。方法:110例AECOPD患者随机分为对照组与观察组,每组55例。两组均给予常规治疗,对照组在此基础上给予孟鲁司特钠片治疗,观察组在对照组基础上采用肺康复综合治疗。比较两组患者ICU住院时间、总住院时间、住院病死率、生活质量评分、第1秒用力呼吸容积(FEV1)、FEV1/最大呼气容积(FVC)、氧分压(PaO_(2))、二氧化碳分压(PaCO_(2))、C反应蛋白(CRP)及α1-抗胰蛋白酶(α1-AT)水平。结果:与治疗前比较,两组FEV1、FEV1/FVC、Pa0_(2)升高,PaCO_(2)降低,差异有统计学意义(P<0.01);治疗后观察组上述指标优于对照组(P<0.01)。CRP及α1-AT水平均明显低于本组治疗前(P<0.01),观察组治疗后CRP明显低于对照组治疗后(P<0.01),差异均具有统计学意义。治疗后观察组总体健康、日常生活能力、疼痛、性生活、积极感受及对医疗手段的依赖评分均明显高于本组治疗前及对照组治疗后(P<0.05,P<0.01)。观察组ICU住院时间、总住院时间及病死率均明显小于对照组(P<0.05,P<0.01)。结论:肺康复综合治疗AECOPD疗效显著,临床应加以推广。

突发重大公共卫生事件中信息疫情防治策略研究

突发重大公共卫生事件涉及范围广泛、影响区域庞大,对社会发展以及人民生命健康构成重大威胁。信息疫情防治策略的研究在突发重大公共卫生事件中起着举足轻重的作用。本文从背景、挑战、策略以及未来展望4个方面,探讨了突发重大公共卫生事件背景下的信息疫情防治策略。通过运用信息化技术构建突发重大公共卫生事件防控体系,普及健康教育和卫生知识,建立突发重大公共卫生事件知识库,将能够更为有效地预防和控制突发重大公共卫生事件的扩散,保障社会稳定以及人民身心健康。

Influence of hypoxia on retinal progenitor and ganglion cells in human induced pluripotent stem cell-derived retinal organoids

AIM:To observe the effect of low oxygen concentration on the neural retina in human induced pluripotent stem cell(hiPSC)-derived retinal organoids(ROs).METHODS:The hiPSC and a three-dimensional culture method were used for the experiments.Generated embryoid bodies(EBs)were randomly and equally divided into hypoxic and normoxic groups.Photographs of the EBs were taken on days 38,45,and 52,and the corresponding volume of EBs was calculated.Simultaneously,samples were collected at these three timepoints,followed by fixation,sectioning,and immunofluorescence.RESULTS:The proportion of Ki67-positive proliferating cells increased steadily on day 38;this proliferationpromoting effect tended to increase tissue density rather than tissue volume.On days 45 and 52,the two groups had relatively similar ratios of Ki67-positive cells.Further immunofluorescence analysis showed that the ratio of SOX2-positive cells significantly increased within the neural retina on day 52(P<0.05).In contrast,the percentage of PAX6-and CHX10-positive cells significantly decreased following hypoxia treatment at all three timepoints(P<0.01),except for CHX10 at day 45(P>0.05).Moreover,the proportion of PAX6-/TUJ1+cells within the neural retinas increased considerably(P<0.01,<0.05,<0.05 respectively).CONCLUSION:Low oxygen promotes stemness and proliferation of neural retinas,suggesting that hypoxic conditions can enlarge the retinal progenitor cell pool in hiPSC-derived ROs.

Amplification and Bioinformatics Analysis of vscN Gene from Vibrio alginolyticus

[Objectives]The paper was to clone and analyze bioinformatics of vscN gene from Vibrio alginolyticus.[Methods]A pair of specific primers was designed based on the vscN gene sequence of V.alginolyticus HY9901.The full length of vscN gene was amplified by PCR and bioinformatics analysis was performed.[Results]The vscN gene was 1323 bp in total,encoding 440 amino acids,with the theoretical molecular weight of 47.86 kD and the theoretical pI value of 5.89.The online prediction showed that there was no signal peptide and no transmembrane region in VscN.The amino acid sequence had 10 N-myristoylation sites,8 phosphorylation sites(2 protein kinase C phosphorylation sites,6 casein kinase II phosphorylation sites),1 amidation site,11 microbody C-terminal target signal sites,1 ATP/GTP binding site motif A(P ring),and 1 ATPaseαandβsubunit specific site.Homology analysis showed that the VscN protein of V.alginolyticus had high homology with that of V.antiquarius,with a similarity of 95.14%.Phylogenetic tree analysis showed that the VscN of V.alginolyticus was clustered into the same subgroup as that of V.diabolicus and V.antiquarius.Functional domain analysis of VscN protein showed that it had Pfam and AAA domains,and involved in the regulation of bacterial virulence.The three-dimensional structure model of VscN simulated by SWISS-MODEL software was similar to the structure of flagellate-specific ATPase FliH-FliI complex.[Conclusions]The results lay a foundation for further study on the regulatory mechanism of VscN protein on bacterial virulence.

Exploring the potential molecular mechanism of JinlingziSan in the treatment of endometriosis based on network pharmacology system

Background:Chinese herbal medicines have been proven to be effective in clinical treatment and disease prevention.Jinlingzi San is a herbal medicine used for the treatment of endometriosis.However,a comprehensive network pharmacology approach has not been used to understand the active ingredients and therapeutic mechanisms behind Jinlingzi San in the treatment of endometriosis.Methods:A network pharmacology approach and a molecular docking approach were used to predict the active ingredients and potential targets of Jinlingzi San in the treatment of endometriosis.Results:The integrated network pharmacology approach successfully identified 60 active ingredients and 540 key targets of action in Jinlingzi San dispersion.Among them,STAT3,TP53,MAPK3,RELA,MAPK1,JUN and other key genes were mainly regulated through pathways in cancer,lipid and atherosclerosis,AGE-RAGE signaling pathway in diabetic complications,pancreatic cancer,prostate cancer,PI3K-Akt signaling pathway,Th17 cell differentiation,and other signaling pathways in the cell body,receptor complexes,cytoplasm,nucleoplasm,and plasma membrane.Conclusion:Based on a systems network pharmacology approach,our work successfully predicts the active components and potential targets of Jinlingzi San for the treatment of endometriosis and helps to illustrate the mechanism of action at an integrative level.This demonstrates that Jinlingzi San for the treatment of endometriosis is regulated through a multi-component,multi-target,multi-system co-regulation.This study identifies key genes and pathways associated with endometriosis and pathogenesis from new insights,and also provides a viable approach to the chemical basis and pharmacological studies of Jinlingzi San.

长期不同施肥模式对大麦–双季稻田根际土壤有机氮组分的影响

根际土壤有机氮组分在土壤养分和作物氮素营养中具有重要作用。本研究依托长期(37年)定位施肥试验田,设置4个施肥处理:不施肥对照(CK)、单独施用化肥(CF)、秸秆还田+化肥(RF)和30%有机肥+70%化肥(OM),于晚稻成熟期测定大麦–双季稻田根际土壤基础理化性质、微生物生物量氮和有机氮组分(氨基酸态氮、氨基糖态氮、酸解氨态氮、酸解未知态氮、非酸解性氮)含量。研究表明:相对CK处理,RF和OM处理显著增加了稻田根际土壤有机碳、全氮、铵态氮和硝态氮的含量。RF和OM处理土壤微生物生物量氮含量分别比CK处理增加了19.8%和30.7%。酸解性氮作为根际土壤全氮的主体部分,占全氮的59.61%~72.06%;各处理根际土壤酸解性氮含量大小顺序表现为OM>RF>CF>CK。各施肥处理中,酸解有机氮中的氨基糖态氮、氨基酸态氮和酸解未知态氮含量均以OM处理最大,分别比CK处理增加139.3%、47.9%和110.0%;酸解氨态氮以RF处理最大,比CK处理增加69.9%。土壤有机碳、全氮、铵态氮、硝态氮与土壤氨基酸态氮、氨基糖态氮、酸解未知态氮以及微生物生物量氮均呈极显著(P<0.01)正相关。因此,秸秆、有机肥配施化肥均能有效提高大麦–双季稻田根际土壤的供氮能力,是改善稻田土壤肥力的有效手段。

金属有机框架材料MIL-101在吸附去除水中有机污染物中的应用进展

金属有机框架材料(MOFs)是一种极具前景的水中污染物吸附材料,其中,拉瓦锡研究所材料(MIL)凭借较好的稳定性和较多的可调节位点在众多MOFs中脱颖而出。与其他MILs相比,MIL-101具有比表面积较大和表面活性位点多的特点,在水中的稳定性高,已成为一种新兴的吸附材料。鉴于此,该文对近年来MIL-101在水中有机污染物去除领域的应用研究进行了综述,主要对MIL-101结构、改性修饰及其在水污染物吸附去除方面的应用及吸附机理进行了介绍。最后对MIL-101吸附材料的应用前景进行了分析和展望。

水稻穗发芽遗传与分子机制的研究进展

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