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Bird Species Diversity and Spatio-temporal Variation in the Sihong Hongze Lake Wetland National Nature reserve in Eastern China

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Journal of Resources and Ecology 2024年第4期15卷 826-837页

作者： HU Huali XIAO Lihui ZHANG Manyu WANG Silu CHEN Taiyu LU Changhu college of Life Science Nanjing Forestry UniversityNanjing 210037China Eastern Hongze Lake Wetland natural reserve HuaianJiangsu 223100China Institute of Wildlife Conservation Jiangxi Academy of ForestryNanchang 330037China

As an important hub on the East Asian-Australian Flyway(EAAF),Hongze Lake is an important migratory stopover and wintering site for hundreds of thousands of ***,research on bird community diversity in this area is still *** conducted a bird survey from July 2020 to June 2021 using the line transect method on the terrestrial habitat,as well as the fixed-point method in the lake wetland at the Sihong Hongze Lake Wetland National Nature reserve located in northwestern Hongze Lake,and analyzed the temporal-spatial variation in the bird *** results showed that a total of 170432 detections of 215 bird species belonging to 18 orders and 55 families were *** terms of species composition,the proportion of terrestrial birds was relatively high,followed by waterfowl richness,with high numbers of Anatidae species and *** bird species abundance,waterfowl had the highest abundance of common coot(Fulica atra),belonging to the Rallidae family,followed by Anatidae and Ardeidae *** abundance of shorebirds was extremely low,and that of non-waterfowl was also *** terms of temporal patterns,the number of bird species and richness index were higher in spring and autumn but lower in winter and *** bird abundance was the highest in winter,and the remaining three seasons were similar in terms of bird *** diversity index and evenness index were higher in spring,summer and autumn,and lowest in *** the spatial pattern,the open water in the western part of the reserve included the most densely distributed areas for birds,and the number of bird species and their abundance were both the highest in that *** were significant differences in the bird community structures among the four *** species number and richness index of birds in the reed habitat were the highest,and the bird abundance was also high,but the diversity index and evenness index were *** the bird abundance in the lake habitat wa

关键词： bird diversity seasonal variation spatial distribution Sihong Hongze Lake Wetland National Nature reserve

A multi-enzymatic cascade reaction for the synthesis of bioactive C-oligosaccharides

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Chinese Chemical Letters 2024年第6期35卷 451-455页

作者： Kebo Xie Qian Zhang Fei Ye Jungui Dai State Key Laboratory of Bioactive Substance and Function of natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs and NHC Key Laboratory of Biosynthesis of Natural ProductsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

C-Oligosaccharides are rare in nature and possess diverse ***,their chemical synthesis faces many *** this work,enzymatic introduction of C-linked sugar chains to target aglycones was successfully achieved by multi-enzymatic cascade reactions.A C-glycosyltransferase from Aloe barbadensis was employed to introduce the first C-linked glucose and then a cyclomaltodextrin glucanotransferase from Bacillus licheniformis was used to extend the sugar chain.A total of twenty C-oligosaccharides with 2-6 sugars were synthesized from scale-up reactions and exhibited good water solubility and sodium-dependent glucose transporter 2(SGLT2)inhibitory ***,a glucoamylase was used to control the length of the sugar chain and the C-maltosides were efficiently *** findings not only expanded the structural diversity of C-oligosaccharides,but also provided a strategy for the modification of C-glycoside drugs to improve the druggability.

关键词： C-Oligosaccharides C-Glycosyltransferase Cyclomaltodextrin glucanotransferase Glucoamylase Enzymatic synthesis SGLT2 inhibitory activity

A fungal CYP from Beauveria bassiana with promiscuous steroid hydroxylation capabilities

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Chinese Chemical Letters 2024年第5期35卷 218-222页

作者： Yu Peng Yue Wang Tian-Jiao Chen Jing-Jing Chen Jin-Ling Yang Ting Gong Ping Zhu State Key Laboratory of Bioactive Substance and Function of natural Medicines NHC Key Laboratory of Biosynthesis of Natural ProductsCAMS Key Laboratory of Enzyme and Biocatalysis of Natural DrugsInstitute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Hydroxylation of steroid core is critical to the synthesis of steroid *** sp^(3) C-H hydroxylation is challenging through chemical catalysis,alternatively,fungal biotransformation offers a possible solution to this ***,mining and metabolic engineering of cytochrome P450 monooxygenases(CYPs)is usually regarded as a more eco-friendly and efficient ***,we report the mining and identification of a new steroid CYP(CYP68BE1)from Beauveria bassiana by transcriptomics,heterologous expression,in vivo and in vitro functional *** catalytic promiscuity of CYP68BE1 was explored,and CYP68BE1 showed promiscuously and catalytically versatile,which is qualified for monohydroxylation on C11α,C1α,C6βand dihydroxylation on C1β,11αand C6β,11αof six steroids,leading to the production of key steroid intermediates required in the industrial synthesis of some indispensable steroid *** dynamics simulations were performed,revealing the molecular basis of different binding orientations of CYP68BE1 with different *** discovery of CYP68BE1 offers a promising biocatalyst for enriching the steroid structural and functional diversity,which also can be applied to biosynthesize valuable steroid drug intermediates.

关键词： Fungal CYPs Steroid hydroxylase Beauveria bassiana Promiscuous biocatalyst Molecular dynamics

Hyperspectral remote sensing identification of marine oil spills and emulsions using feature bands and double-branch dual-attention mechanism network

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Journal of Oceanology and Limnology 2024年第3期42卷 728-743页

作者： Ning ZHANG Junfang YANG Shanwei LIU Yi MA Jie ZHANG college of Oceanography and Space Informatics China University of PetroleumQingdao 266580China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill *** selection of characteristic bands with strong separability helps to realize the rapid calculation of data on aircraft or in orbit,which will improve the timeliness of oil spill emergency *** the same time,the combination of spectral and spatial features can improve the accuracy of oil spill *** ground-based experiments were designed to collect measured airborne hyperspectral data of crude oil and its emulsions,for which the multiscale superpixel level group clustering framework(MSGCF)was used to select spectral feature bands with strong *** addition,the double-branch dual-attention(DBDA)model was applied to identify crude oil and its *** with the recognition results based on original hyperspectral images,using the feature bands determined by MSGCF improved the recognition accuracy,and greatly shortened the running ***,the characteristic bands for quantifying the volume concentration of water-in-oil emulsions were determined,and a quantitative inversion model was constructed and applied to the AVIRIS image of the deepwater horizon oil spill event in *** study verified the effectiveness of feature bands in identifying oil spill pollution types and quantifying concentration,laying foundation for rapid identification and quantification of marine oil spills and their emulsions on aircraft or in orbit.

关键词： hyperspectral image spectral analysis dimensionality reduction multiscale superpixel level group clustering framework(MSGCF) double-branch dual-attention(DBDA)

Straw return decreases polycyclic aromatic hydrocarbon(PAH) accumulation in winter wheat and human health risk by enhancing PAH dissipation in rhizosphere soil

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Pedosphere 2024年第4期34卷 699-708页

作者： Jun CAI He ZHANG Xiangyao WU Yifan LIU Yunmei WU Jinfeng WANG Chuangye ZHANG Benhua SUN Fuyong WU college of natural Resources and Environment Northwest A&F University Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of Agriculture

Straw return in situ, a common agronomic measure in China, has been widely used not only to increase crop yields and improve soil nutrients but also to remove polycyclic aromatic hydrocarbons(PAHs) from agricultural soils. Nevertheless, the safety risks of food crops(i.e., human health risk of wheat grains) grown in PAHs-contaminated agricultural soils amended with crop straw remain uncertain. A pot experiment was conducted in a PAHs-contaminated agricultural soil cultivated with winter wheat under different ratios of corn straw addition(0%(control, CK), 1%, 2.5%, and 5%, weight/weight). Results showed that corn straw addition significantly(P < 0.05) decreased PAH concentrations in rhizosphere soil, roots, straws, and grains by 48.32%–50.01%,11.85%–42.67%, 9.78%–28.03%, and 14.16%–31.67%, respectively, compared with CK, whereas the transfer factors of PAHs from roots to straws were significantly(P < 0.05) increased. A correlation heatmap showed that PAH concentrations in roots, straws, and grains were positively(P < 0.01) correlated with those in rhizosphere soil. These indicated that corn straw decreased PAH accumulation in winter wheat due to the increase of PAH dissipation in the rhizosphere soil, although it enhanced PAH transfer in winter wheat. The incremental lifetime cancer risk(ILCR) model indicated that corn straw significantly(P < 0.05) decreased the human health risk of winter wheat grains by 29.73%–45.05%. Overall, corn straw apparently reduced PAH accumulation in winter wheat, ecological risk, and human health risk via enhancing PAH dissipation in the rhizosphere soil. These findings provide an important scientific basis and theoretical guidance for agricultural safety production.

关键词： corn straw addition ecological risk food crops incremental lifetime cancer risk transfer factor

Effects of longitudinal magnetic field on primary dendrite spacing and segregation of directionally solidified single crystal superalloy

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Progress in natural Science:Materials International 2024年第1期34卷 26-36页

作者： Congjiang Zhang Yilin Zhou Chen Shen Weili Ren Xiaotan Yuan Biao Ding Haibiao Lu Zuosheng Lei Yunbo Zhong Ang Zhang State Key Laboratory of Advanced Special Steel College of Materials Science and Engineering Shanghai University National Engineering Research Center for Magnesium Alloys Natural Key Laboratory of Advanced Casting Technologies College of Materials Science and EngineeringChongqing University

The primary dendrite spacing(PDS) and segregation of directionally solidified single crystal(SC) superalloy under the longitudinal magnetic field(LMF) were investigated based on the analysis of the whole cross-sectional microstructure at different solidification distances. The results show that the PDS under the LMF remains basically unchanged at different solidification distances, and it is greater than that under no LMF. With the increase of magnetic field intensity, the PDS increases and the macrosegregation decreases. The increasing PDS and reducing segregation under the LMF can be attributed to the increase of solute boundary layer, which expands the non-equilibrium freezing temperature range and brings the effective partition coefficient closer to 1. The increase of the solute enrichment layer thickness could be caused by the downward secondary circulation generated by the thermoelectric magnetic convection(TEMC) near the interface, which drives the migration of solutes towards the interdendritic region. This work not only clarifies the mechanism of LMF controlling PDS and reducing segregation by TEMC, but also provides theoretical guidance for producing high-quality SC superalloys using magnetic fields.

关键词： Primary dendrite spacing Segregation Single crystal superalloy Directional solidification Magnetic field Thermoelectric magnetic convection

Phosphine-catalyzed acyl-transfer of heteroaryl ketones for the construction of N-fused heterocycles

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Chinese Chemical Letters 2024年第3期35卷 252-256页

作者： Yu Zhang De-Rui Han Dan Ye Hong Lu Hao Wei Key Laboratory of Synthetic and natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069China

An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of N-containing heteroaryl ketones for the rapid synthesis of N-fused *** key pre-aromatic spirocyclic intermediate initialized by the single electron transfer(SET)process of Togni's reagentⅡpromoted by the tertiary phosphine resulted in an intriguing and alternative tactic for the cleavage of C–C *** using inexpensive tertiary phosphine as the catalyst,this skeleton-reorganizing approach of N-containing heteroaryl ketones allows a streamlined assembly of complex N-fused heterocycles with broad functional group tolerance.

关键词： Phosphine catalysis Acyl-transfer N-Fused heterocycles C–C bond activation Aromatization

Enhancement of catalytic activity for hydrogenation of nitroaromatic by anionic metal-organic framework

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Chinese Chemical Letters 2024年第3期35卷 144-148页

作者： Qi Wu Anyang Li Ruibo He Yaxi Wu Lei Hou Guoping Yang Wenyan Zhang Yao-Yu Wang Key Laboratory of Synthetic and natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710127China

Nitroaromatic hydrogenation catalysis without precious metals remains a longstanding *** rate of electron transfer is the crucial factor affecting hydrogenation ***,an ionic Cd-based metal-organic framework(I-Cd-MOF)exhibiting a unique structure with one-dimensional(1D)opening nanochannels and good electron transfer ability was synthesized for catalyzing hydrogenation of 4-nitrophenol(4-NP).The catalytic activity of the unique I-Cd-MOF without noble metals is detected,which is higher than most reported noble metal ***,the reaction rate of I-Cd-MOF(4.28 min^(-1))is about 47.6 times higher than that of the Cd-based neutral MOF(N-Cd-MOF)with the similar crystalline *** chromatograph mass spectrometer(LC-MS)and theoretical results demonstrate that 4-NP and five intermediates are stabilized in the channels of I-Cd-MOF,which increases the possibility of contact with H^*and H_(2)g enerated at the Cd *** I-Cd-MOF was extended to other nitroaromatic hydrogenation catalysis,which still displays excellent *** importantly,the I-MOF@Filter membrane was successfully constructed for continuous hydrogenation catalytic reactions,which maintains a high catalytic performance after 7 cycles of recycling without *** work fills in the application of the I-MOFs in hydrogenation catalytic reactions and provides an effective way for the rapid and green degradation of nitroaromatic compounds.

关键词： Anions Metal-organic frameworks Catalysis Electron transfer Hydrogen production

Morphological comparison and molecular marker screening of three Skeletonema species found in Changjiang(Yangtze)River Basin

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Journal of Oceanology and Limnology 2024年第3期42卷 923-942页

作者： Jingwen HU Yuxin YI Zhengxin YANG John Patrick KOCIOLEK Pan YU Quanxi WANG Qingmin YOU college of Life Sciences Shanghai Normal UniversityShanghai 200235China Museum of natural History University of ColoradoBoulder 80309USA college of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200235China

In our recent investigations of diatom diversity,we studied three species,namely,Skeletonema costatum,Skeletonema subsalsum,and Skeletonema *** they have been found frequently in Changjiang(Yangtze)River Basin,their morphological and molecular identification is difficult in ***,to integrate morphological and molecular biological approaches,we compared systematically their morphological characters and performed phylogenetic *** strains of Skeletonema were collected and isolated from Shanghai and Jiangsu,China,and their morphological characteristics were examined by light microscopy(LM)and the scanning electron microscopy(SEM).Based on morphological comparison,we determined that *** is easy to distinguish from the other two *** heavily silicified areolae,undulated or cleft distal ends of terminal fultoportula processes(TFPPs),absence of basal pores of fultoportula processes(FPPs),the rootlike protrusions of FPPs,and no interlocking connection are the stable characteristics that can be used to identify ***,there are only two features that can distinguish *** from ***,namely the location of terminal rimoportulae(TRPs)and the distal shape of *** addition,we amplified and sequenced nine common genetic markers from the strains,from which 101 sequences were obtained,constructed phylogenetic trees based on the nine genes and evaluated that seven genes can be used to identify ***,and revealed that *** is the closest known relative of ***,and only ATP synthetase beta-subunit gene(atp B)is able to distinguish them from each other,which strongly support that it is an effective molecular marker for *** work provided a theoretical basis for the taxonomic study of Skeletonema.

关键词： Skeletonema Changjiang River morphological change distinguishing morphological characteristics molecular marker