人工智能新时代下教学改革的新思考

随着ChatGPT-4的推出,人工智能技术的发展与应用进入了一个崭新的时代,也必然对现代科技人才的培养产生深远的影响。本文首先简述了人工智能技术及其在化学研究中的应用;其次,探讨了在人工智能新时代下化学专业学生创新能力培养的新要求;最后,介绍了我院《化学信息学》课程教学改革的探索与实践。

Identification of the HAK gene family reveals their critical response to potassium regulation during adventitious root formation in apple rootstock

Adventitious root formation is a bottleneck during vegetative proliferation.Potassium(K^(+))is an essential macronutrient for plants.K^(+)accumulation from the soil and its distribution to the different plant organs is mediated by K^(+)transporters named K^(+)transporter(KT),K^(+)uptake(KUP),or high-affinity K^(+)(HAK).This study aimed to identify members of the HAK gene family in apples and to characterize the effects of K^(+)supply on adventitious root formation and on the expression of HAK genes and the genes that putatively control auxin transport,signaling,and cell fate during adventitious root formation.In this study,34 HAK genes(MdHAKs)were identified in the apple(Malus×domestica‘Golden Delicious’)genome.A phylogenetic analysis divided MdHAKs into four clusters(Ⅰ,Ⅱ,Ⅲ,andⅣ),comprising 16,1,4,and 13 genes,respectively.The syntenic relationships revealed that 62.5%of the total MdHAK genes arise from genomic duplication events.Chromosome location,domain structure,motif analysis,and physico-chemical characteristics were subsequently investigated.Furthermore,the application of K^(+)indicated the emergence of adventitious roots at 8 d and produced more adventitious roots at 16 d than the K^(+)-free control(CK)treatment.In addition,various MdHAKs showed root-specific expression in B9 apple rootstock stem cuttings and enhanced expression during the initiation and emergence stages of adventitious root formation in response to K^(+)treatment.Additionally,K^(+)treatment enhanced the expression levels of MdPIN1,MdPIN2,and MdAUX1.Further data indicated that a higher expression of MdWOX11,MdLBD16,and MdLBD29 and of cell cycle-related genes contributed to the auxin-stimulated adventitious root formation in response to K^(+).

反相乳液法聚合制备耐高温体积膨胀聚合物微球

以单硬脂酸甘油酯(GMS)为乳化剂、四烯丙基氯化铵(TAAC)为交联剂,通过反相乳液聚合制备了一种耐高温P(AM-AANa)聚合物微球。聚合物微球较优的合成条件是,交联剂和引发剂占单体的质量分数分别为0.8%和0.1%,mAM:mAA=0.5,m白油:mGM=5,m水相:m油相=2,在该条件下合成的微球吸水倍率为68.4 g/g,粒径为原来的29倍。傅里叶变换红外光谱、X射线能量色散谱、扫描电镜和激光粒度仪分析结果表明,聚合物微球具有较好的球形度,聚合物微球在180℃时,分别在蒸馏水及在现场水中吸水10 d之后仍保持较好的球形,说明微球具有优良的耐高温稳定性。

Emergency management of nursing human resources and supplies to respond to coronavirus disease 2019 epidemic

Objective:To introduce the emergency management of nursing human resources and supplies of a large general hospital when facing the outbreak of coronavirus disease 2019(COVID-19).Method:The Nursing Department of the hospital fully executed its functional authority to establish a three-level echelon of sustainable support,allocate human recourses dynamically,organize pre-service training,supervise the key working steps,formulate positive incentive methods,and deploy medical supplies scientifically.Result:By taking these strategies,the hospital effectively improved the coping capacity of the nursing team and played a positive role in the prevention and treatment of COVID-19.Conclusion:The emergency management of nursing human resources and material resources for COVID-19 of the hospital is successful.But several deficiencies were identified as well,which indicated that the hospital needs to establish an efficient emergency management system,and pay attention to the practice of nursing emergency plans to enhance coping capacities in public health emergencies.

采用Barbier缩聚反应制备自修复材料

通过呋喃甲酸甲酯和1,10-二溴癸烷的Barbier缩聚反应制得预聚物,凝胶渗透色谱测试结果表明制备的预聚物数均相对分子质量为9700,相对分子质量分布指数为1.23。将该预聚物与N,N′-(4,4′-亚甲基二苯基)双马来酰亚胺(BMI)反应制备了一种基于热可逆Diels-Alder键的自修复薄膜。通过显微镜观察自修复薄膜的裂纹修复效果,该薄膜可以在65℃,1 min内完成对裂纹的修复,具有优良的自修复性能。热重测试表明,自修复薄膜具有良好的热稳定性,当将薄膜材料加热到280℃时,自修复薄膜的质量仅减少5%。

Nitrate application affects root morphology by altering hormonal status and gene expression patterns in B9 apple rootstock nursery plants

Lateral roots(LRs)are critical for absorbing water,minerals,and nutrients.Nitrate is a vital signaling molecule for regulating LR growth.However,understanding how nitrate interacts with endogenous hormones and genes to coordinate LR development is a bottleneck.In this study,B9 apple rootstock nursery plants were cultured hydroponically and treated with different nitrate treatments(Control;T1,2.25 mM L^(−1);T2,9 mM L^(−1);T3,18 mM L^(−1);T4,36 mM L^(−1);and T5,72 mM L^(−1)),where T5 outperformed the other treatments.Nursery plants were subsequently treated with control and T5 to explore the underlying physiological and molecular mechanisms by which nitrate promoted LR growth.Plant height,stem diameter,root morphological parameters,endogenous hormones,and gene expression levels were measured.Results showed that T5 promoted LR growth by increasing the endogenous contents of indole-3-acetic acid(IAA)and gibberellic acid(GA),and by decreasing the contents of abscisic acid(ABA),jasmonic acid(JA),and zeatin riboside(ZR)at most time points.Furthermore,the relative expression levels of nitrate transporter genes were upregulated in the control group,and nitrate assimilation genes were upregulated in T5 nursery plants at various time points.In addition,the transcript abundances of auxin-related genes were higher in T5 nursery plants,which increased auxin contents.MdSHR,MdGATA1,and MdSCR1 expressions were induced,hence increasing LR growth.In contrast,higher auxin content raised MdWOX11 expression,which enhanced the MdLBD16 and MdLBD29 expression levels,thus prompting the transcripts of cell cycle-related genes:MdCYCD1;1 and MdCYCP4;1.Overall,the changes in hormonal content and gene expression levels followed superior LR growth by T5.

具有聚集诱导发光性能的三苯甲醇侧基聚合物的制备及性能

通过Barbier反应合成了乙烯基三苯甲醇,其具有聚集诱导发光(AIE)现象;通过可逆加成-链转移(RAFT)聚合的方法将乙烯基三苯甲醇聚合得到不同相对分子质量的聚(三苯甲醇)乙烯。发现该聚合物表现出不同于小分子的AIE特性,在常温固态或溶液状态下均不产生荧光,但加热至玻璃化转变温度之后,聚合物固体的荧光发射强度明显增强,在溶液中依然不产生荧光。文中针对其特殊发光现象及发光机理进行了初步探究,通过核磁共振氢谱、红外光谱、X射线衍射与热力学表征发现其荧光的变化与激基缔合物有关。

Nutrient status of Populus euphratica growing in desert riparian forests of northwestern China

Seasonal and microhabitat variations of chemical constituents of foliar organic carbon （C）, total nitrogen （N）, total phosphorus （P）, and total potassium （K）, in Populus euphratica growing in desert riparian forests in northwestern China and their correlations were studied. Results show that ranges of C, N, P and K contents in the leaves ofP. euphratica were 39.08%-46.16%, 0.28%-2.81%, 0.05%-0.18% and 0.35%-2.03%, with means of 43.51%, 1.49%, 0.102% and 1.17%, respectively. The ratio of C/N, C/P and N/P changed from 16.26 to 146.61, from 258.08 to 908.67 and from 2.89 to 26.67; the mean was 37.24, 466.27 and 15.14, respectively. The mean N content was significantly lower than of deciduous trees in China, but the mean P content was nearly equivalent. The ratio of C/N was remarkably higher than of global land plants. The ratio of N/P indicated that growth ofP. euphratica was jointly limited by N and P nutrient deficiency. During the growth season, total trends of leaf C, N, P and K contents decreased. The max- imum appeared in May, and the minimum in September. Among microhabitats, C, N and K contents gradually increased from ri- parian lowland, flatland, sandpile, Gobi and dune, but C/N ratio was opposite, and P content was not apparent. Foliar C content was extremely, significantly and positively correlated with N and K contents, respectively. The relationships of N-K and P-K were both significantly positive.

Comparison of leaf morphological,anatomical,and photosynthetic responses to drought stress among eight apple rootstocks

The drought resistance of eight commonly used apple rootstocks under natural drought conditions was examined to provide clues for the selection,promotion,and utilization of drought-resistant apple rootstocks.The ultrastructural differences and physiological and biochemical characteristics of the leaves of eight apple rootstocks under drought stress were observed.The index changes were used to rank drought resistance by the membership function method comprehensively.The results showed that the leaf thickness,palisade tissue thickness,sponge tissue thickness,net photosynthetic rate,and chlorophyll content were significantly higher in‘Fupingqiuzi'than those of other rootstocks at various stress conditions.The leaf water content and water use efficiency of'Qingzhen 1'were significantly higher than those of other rootstocks under different stress conditions.The root vigor of‘B.9'was significantly higher than that of other rootstocks.The results of membership function analysis showed that the drought resistance of different rootstocks was in the order:‘Fupingqiuzi'>‘Qingzhen 1'>‘B.9'>‘MM.111'>‘GM256'>‘MM.106'>‘M.26'>‘M.9-Nic29'.‘Fupingqiuzi'had the strongest drought resistance,and‘Qingzhen 1'and‘B.9'were also relatively droughtresistant.These rootstocks can be used as raw materials for drought-resistant apple rootstock breeding and are propagated and utilized in arid areas.

Storage, form, and influencing factors of karst inorganic carbon in a carbonate area in China

Carbonate rock chemical weathering carbon sinks reduce the rate of increase of the atmospheric CO_(2) concentration and global warming. However, uncertainty still exists in the estimation results of carbonate rock chemical weathering carbon sink fluxes(CCSF), and the contributions of climate change and ecological restoration to the CCSF are not clear. To this end, we compiled published site data on ion concentrations in different watersheds in China and used a classical thermodynamic dissolution model to reassess the potential and spatial and temporal patterns of the CCSF in China from 1991 to 2020. We quantified the contributions of temperature(MAT), precipitation(MAP), evapotranspiration(ET), soil water(SM), and the normalized difference vegetation index(NDVI) to the CCSF. The results revealed that(1) China's CCSF was 22.76 t CO_(2)km^(-2)yr^(-1), which was higher than the global average(15.77 t CO_(2)km^(-2)yr^(-1)). The total carbonate rock chemical weathering carbon sink(CCS) was 4772.67×10^(4)t CO_(2), contributing 14.91% of the global CCS through a carbonate rock area of 252.98×10^(4)km^(-2).(2) China's CCSF decreased gradually from southeast to northwest, with values of 33.14, 12.93, and7.27 t CO_(2)km^(-2)yr^(-1)in the southern karst, Qinghai-Tibetan karst, and northern karst regions, respectively.(3) The overall CCSF in China exhibited an increasing trend from 1991 to 2020, with a rate of increase of 0.16 t CO_(2)km^(-2)yr^(-1).(4) The contributions of the MAP, MAT, ET, SM, and NDVI to the CCSF were 63.3%, 3.02%, 27.5%, 3.1%, and 3.05%, respectively. Among them, the increase in precipitation was the main contributor to the increase in the CCSF in China over the last 30 years, while the enhancement of ET offset part of the positive contribution of the increase in precipitation to the CCSF. In conclusion, the results of this study provide a systematic quantification of the magnitude, the patterns, and the influencing factors of CCS over a long time series in China. The results are of great significance and provide a reference for the diagnosis and gap analysis of the national and global carbon neutrality capacities.

中国喀斯特生态系统健康诊断的方法、进展与展望

中国是碳酸盐岩型喀斯特面积最大、分布最广的国家,在喀斯特地区居住着约2亿的人口,经济规模约占全国的10%.尤其是以贵州为中心的西南地区,位于长江和珠江的上游,经济欠发达,但却是国家的重要生态安全屏障.喀斯特地貌重要而特殊,科学诊断其生态系统的健康不仅对生态修复和实现可持续发展至关重要,更是制定应对方案的基本前提.尽管以往开展了大量的研究工作,但是依然缺乏系统性和整体性认识.本文结合前人研究,进一步将喀斯特地貌演化发育总结为6个阶段:成岩阶段、成陆阶段、成山阶段、成丛阶段、成林阶段和成原阶段.在此基础上,又从碳酸盐岩风化成土速率的计算、土壤水的诊断、水土流失的评价、石漠化解译与演变、生态系统服务的科学计量5个方面进行系统的总结和梳理.尽管不同时代、不同学者的不同研究方法,其结果有着非常大的差异.但是,综合考虑已有的研究结果及其使用方法的优点和不足,归纳发现:(1)碳酸盐岩化学风化很快(30~130 mm ka^(−1)),但由于其酸不溶物含量低(5%以内),导致其成土速率极其缓慢,一般在5~50 t km^(−2)a^(−1)之间.(2)土壤少且分布不连续,但是土壤含水量却比较高,在0.2~0.4 m^(3)m^(−3)之间,这可能与周边基岩的汇水效应相关,且未来呈干化趋势.(3)土壤侵蚀模数低,一般在2~200 t km^(−2)a^(−1)之间,但由于坡陡、降雨量大且与岩土突变接触,导致其侵蚀风险极大,并存在一定比例的地下漏失现象.(4)石漠化的演变可分为单变式、渐进式和返变式3种经典类型,但是通过决策树和人机交互的石漠化解译方法相对高效和精准.(5)喀斯特生态系统服务功能的评价模型要基于成土速率来进行修正水土保持功能和基于岩溶地质碳汇修正气候调节功能.当前诊断喀斯特生态系统健康的指标、方法和模型亟须改进和创新,要充分体现喀斯特地区的特殊性和模型方法的匹配性,提高监测数据的时空分辨率,特别是亟须建立喀斯特社会-生态系统耦合模型,准确刻画出喀斯特生态系统对气候变化和人类活动的响应过程,提升诊断模型的准确度和可预测性.总之,本文系统总结了诊断中国喀斯特生态系统健康与可持续性的方法和取得的重大进展,并进一步从“岩-土-水-石-生”的角度提出了未来的研究方向和突破重点,以期为维护喀斯特地区的生态安全和可持续发展提供科技支撑.

Micropeptides: origins, identification, and potential role in metabolism-related diseases

With the development of modern sequencing techniques and bioinformatics, genomes that were once thought to be noncoding have been found to encode abundant functional micropeptides(miPs), a kind of small polypeptides. Although miPs are difficult to analyze and identify, a number of studies have begun to focus on them. More and more miPs have been revealed as essential for energy metabolism homeostasis, immune regulation, and tumor growth and development. Many reports have shown that miPs are especially essential for regulating glucose and lipid metabolism and regulating mitochondrial function.MiPs are also involved in the progression of related diseases. This paper reviews the sources and identification of miPs, as well as the functional significance of miPs for metabolism-related diseases, with the aim of revealing their potential clinical applications.

Room temperature in-situ preparation of hydrazine-linked covalent organic frameworks coated capillaries for separation and determination of polycyclic aromatic hydrocarbons

Covalent organic frameworks(COFs)have been increasingly used in capillary electrochromatography due to their excellent characteristics.In this work,hydrazine-linked TFPB-DHzDS(TFPB:1,3,5-tris(4-formylphenyl)benzene;DHzDS:2,5-bis(3-(ethylthio)propoxy)terephthalohydrazide)was first synthesized by a simpler and easier method at room temperature and introduced into capillary electrochromatography as coating material.The TFPB-DHzDS coated capillaries were prepared by an in-situ growth process at room temperature.After optimizing the coating concentration and experimental conditions of capillary electrochromatography,baseline separation of two groups of polycyclic aromatic hydrocarbons was achieved based on the TFPB-DHzDS coated capillary.And the established method was used successfully to determine PAHs in natural water and soil samples.The spiked recoveries of polycyclic aromatic hydrocarbons in these samples ranged from 90.01%to 111.0%,indicating that the method is reliable and could detect polycyclic aromatic hydrocarbons in natural samples.Finally,molecular simulation was applied to study and visualize the interaction between the analytes and coating COF materials to investigate the molecular level separation mechanism further.

Electrochemical synthesis of Ni doped carbon quantum dots for simultaneous fluorometric determination of Fe^(3+)and Cu^(2+)ion facilely

A novel Ni doped carbon quantum dots(Ni-CQDs)fluorescence probe was synthesized by facile electrolysis of monoatomic Ni dispersed porous carbon(Ni–N–C).The obtained Ni-CQDs showed a high quantum yield of 6.3%with the strongest excitation and emission peaks of 360 nm and 460 nm,and maintained over 90%of the maximum fluorescence intensity in a wide p H range of 3–12.The metal ions detectability of Ni-CQDs was enhanced by Ni doping and functional groups modification,and the rapid and selective detection of Fe^(3+)and Cu^(2+)ions was achieved with Ni-CQDs through dynamic and static quenching mechanism,respectively.On one hand,the energy band gap of Ni-CQDs was regulated by Ni doping,so that excited electrons in Ni-CQDs were able to transfer to Fe^(3+)easily.On the other hand,the abundant functional groups promoted the generation of static quenching complexation between Cu^(2+)and Ni-CQDs.In metal ions detection,the linear quantitation range of Fe^(3+)and Cu^(2+)were 100–1000μM(R^(2)=0.9955)and 300–900μM(R^(2)=0.9978),respectively.The limits of detection(LOD)were calculated as 10.17 and 7.88μM,respectively.Moreover,the fluorescence quenched by Cu^(2+)could be recovered by EDTA2-due to the destruction of the static quenching complexation.In this way,NiCQDs showed the ability to identify the two metal ions to a certain degree under the condition of Fe^(3+)and Cu^(2+)coexistent.This work paves the way of facile multiple metal ion detection with high sensitivity.

解淀粉芽胞杆菌PHODB35的溶磷特性及其对番茄的促生作用

【目的】从种植番茄的根围土壤中筛选高效溶磷细菌,为减施化学肥料和开发微生物肥料提供溶磷菌种资源,并初步探索其促生机制。【方法】采用无机磷培养基利用梯度稀释涂布法从土壤中分离筛选促生菌株,通过形态特征、16S rRNA和gyrB基因序列分析对优良促生菌株进行鉴定,并分别利用正交试验和单因素试验分析环境因子和营养因子对其溶磷效果的影响,进一步利用HPLC-MS并结合相应有机酸的标准物质,明确优良促生菌株产生的有机酸种类;盆栽试验测定接菌处理后番茄株高、地上鲜重、地下鲜重、基质和植株有效磷含量评价菌株对番茄的促生作用。【结果】筛选到1株优良的促生菌株,命名为PHODB35,鉴定其为解淀粉芽胞杆菌(Bacillus amyloliquefaciens)。对环境因子的正交试验结果表明,菌株PHODB35最佳溶磷条件为pH 7.0,温度为30°C,接种量为5%;对营养因子的单因素试验结果表明,该菌株以葡萄糖为碳源、硫酸铵为氮源、磷酸钙为磷源时,解磷效果最好,有效磷浓度为88.77mg/L。明确了菌株PHODB35产生的有机酸为葡萄糖酸。盆栽实验结果表明,菌株PHODB35对番茄幼苗有明显的促生作用,与空白对照相比,施用菌株后对株高、地上鲜重、地下鲜重、基质和植株有效磷含量分别增加28.21%、22.59%、113.06%、45.08%和16.24%,表明菌株PHODB35具有一定的肥效功能,可用于促生菌剂的研制。【结论】筛选到具有促生能力的解磷细菌,为进一步开发研制番茄促生菌剂或微生物有机肥提供资源,为菌株PHODB35在农业生产中的应用提供了理论依据和实验基础。

哈萨克斯坦的生物多样性保护及中哈合作的对策建议

哈萨克斯坦位于欧亚大陆腹地,地处丝绸之路经济带的重要位置。中国与哈萨克斯坦开展生物多样性保护合作,有助于解决地区生态环境问题和推动"一带一路"倡议的顺利实施。目前国内尚缺乏对哈萨克斯坦生物多样性及其保护状况的了解。本文在文献的基础上通过定量和定性分析方法,从地理环境特征、生物多样性状况、保护成效和需求等维度对哈萨克斯坦生物多样性及其保护的总体情况进行了分析。分析结果表明,哈萨克斯坦的生物多样性丰富,但也存在着较严重的丧失问题;哈萨克斯坦政府重视生物多样性保护,积极承担相关国际履约义务;在保护管理方面实行多级管理体制,并与社会经济发展需求相结合,取得了一定成效。

表界面调控电催化析氧反应

开发高效绿色清洁能源已引起研究者们的广泛关注。电解水是一种大规模且可持续生产高纯氢能源技术。然而,阳极析氧反应电催化剂的高过电位和不稳定性制约了电解水技术的大规模应用,合理设计电催化剂的结构可显著优化其反应热力学和动力学,提高电解水技术的能量转换效率。表界面是电催化反应发生的主要场所,通过调控电催化剂表面的本征结构或构筑异质界面等系列表界面化学工程对电催化剂进行改性,可以有效改善材料的催化活性和稳定性。本文概述了当前表界面调控策略在电催化析氧反应中的研究进展,重点介绍了表界面调控层状双金属氢氧化物、钙钛矿型氧化物、尖晶石型化合物及合金材料的研究现状,阐述了高效稳定析氧反应电催化剂的设计思路。讨论了表界面调控策对催化剂表界面微结构和电子态的影响以及设计新型析氧反应电催化剂中面临的问题。最后,展望了表界面调控应用于析氧反应电催化剂的前景。

Multidisciplinary management of recurrent and metastatic hepatocellular carcinoma after resection: an international expert consensus

Hepatocellular carcinoma (HCC) is the sixth-most common cancer and the third leading cause of cancer-related death in the world. However, 40–70% patients eventually suffer from postoperative recurrence within 5 years. HCC recurrence after surgery severely affects prognosis of the patients. Nevertheless, there is an opportunity to improve patients' prognosis if doctors and researchers can recognize the importance of a standardized perioperative management and study it in clinical and pre-clinical settings. Hence, based on our own experience and published studies from other researchers, we develop this consensus regarding multidisciplinary management of locally recurrent and metastatic hepatocellular carcinoma after resection. This consensus consists of the entire course of recurrent hepatocellular carcinoma (RHCC) management, including prediction of recurrence, prevention, diagnosis, treatment and surveillance of RHCC. Consensus recommendations are presented with grades of evidences (Ia, Ib, IIa, IIb, III and IV), and strength ofrecommendations (A, B, C, D and E). We also develop a decision-making path for RHCC treatment, which can intuitively demonstrate the management for RHCC. It is hoped that we may make some effort to standardize the management of RHCC and ultimately understand how to improve outcomes.

Conversion resection for patients with hepatocellular carcinoma and inferior vena cava tumor thrombus: a consecutive case series

To the Editor:The incidence of hepatocellular carcinoma(HCC)with inferior vena cava tumor thrombus(IVCTT)is.approximately 1.4%.Owing to direct cancercll dissemination into the systemic circulation,HCC-IVCTT is frequently associated with synchronous and metachronous extrahepatic metastasis.Without treatment,the median survival time is only 3 months for patients with HCC-IVCTT.