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6-Phosphogluconate dehydrogenase 2 bridges the OPP and shikimate pathways to enhance aromatic amino acid production in plants

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Science China Life Sciences 2024年

作者： Qian Tang Yuxin Huang Zhuanglin Shen Linhui Sun Yang Gu Huiqing He Yanhong Chen Jiahai Zhou Limin Zhang Cuihuan Zhao Shisong Ma Yunhai Li Jie Wu Qiao Zhao Shenzhen Key Laboratory of synthetic Genomics Guangdong Provincial Key Laboratory of Synthetic Genomics Key Laboratory of Quantitative Synthetic Biology Shenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced Technology Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Key Laboratory for Quantitative Engineering biology Shenzhen Institute of Synthetic Biology Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Key Laboratory of Quantitative synthetic biology Shenzhen Institute of Synthetic Biology Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Key Laboratory of Agricultural Microbiology of Heilongjiang Province Northeast Agricultural University Center for Plant biology School of Life Sciences Tsinghua University State Key Laboratory of Plant Cell and Chromosome Engineering CAS Centre for Excellence in Molecular Plant Biology Institute of Genetics and Developmental Biology The Innovative Academy of Seed Design Chinese Academy of Sciences MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics School of Life Sciences University of Science and Technology of China Innovation Academy for Seed Design Chinese Academy of Sciences

The oxidative pentose phosphate(OPP) pathway provides metabolic intermediates for the shikimate pathway and directs carbon flow to the biosynthesis of aromatic amino acids(AAAs), which serve as basic protein building blocks and precursors of numerous metabolites essential for plant growth. However, genetic evidence linking the two pathways is largely unclear. In this study, we identified 6-phosphogluconate dehydrogenase 2(PGD2), the rate-limiting enzyme of the cytosolic OPP pathway, through suppressor screening of arogenate dehydrogenase 2(adh2) in Arabidopsis. Our data indicated that a single amino acid substitution at position 63(glutamic acid to lysine) of PGD2 enhanced its enzyme activity by facilitating the dissociation of products from the active site of PGD2, thus increasing the accumulation of AAAs and partially restoring the defective phenotype of adh2. Phylogenetic analysis indicated that the point mutation occurred in a well-conserved amino acid residue. Plants with different amino acids at this conserved site of PGDs confer diverse catalytic activities, thus exhibiting distinct AAAs producing capability. These findings uncover the genetic link between the OPP pathway and AAAs biosynthesis through PGD2. The gain-of-function point mutation of PGD2 identified here could be considered as a potential engineering target to alter the metabolic flux for the production of AAAs and downstream compounds.

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Selective nano-buckling improves the performance of graphene logic transistors

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National Science Review 2024年第2期11卷 95-96页

作者： Tong Yang Ming Yang Department of applied Physics The Hong Kong Polytechnic University Research centre for Nanoscience and Nanotechnology The Hong Kong Polytechnic University

The massive integration of silicon-based transistors into modern electronic devices greatly increases power consumption and heat generation/dissipation[1]. In this concern, transistors based on atomically-thin graphene that exhibit high electric and thermoelectric conductivities with negligible contact resistance,

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The immune system: uncharted pathways between senses and the brain

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Neural Regeneration Research 2024年第6期19卷 1173-1174页

作者： Noelia Casares Mar Cuadrado-Tejedor Ana García-Osta Juan José Lasarte Immunology and Immunotherapy Program Centre for Applied Medical Research (CIMA) University of NavarraIDISNA Division of Gene Therapy for Neurological Disorders Centre for Applied Medical Research (CIMA) University of NavarraIDISNA Pathology Anatomy and Physiology Department School of Medicine University of NavarraIDISNA

Humans and animals use the classic five senses-sight, hearing, touch, smell, and taste-to detect and monitor their environment, with the sense of position and movement often referred to as the sixth sense. The perception of external signals through the senses is essential to an organism’s survival, transmitting signals to the central nervous system(CNS) and prompting physiological changes in other biological systems. In addition to the direct effects of sense-induced mediators in the brain,

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Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture

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Acta Geochimica 2024年第2期43卷 214-234页

作者： Maria Kaleem Erum Bashir Shahid Naseem Tahir Rafique Bushra Shahab Department of Geology University of KarachiKarachi 75270Pakistan applied Chemistry Research centre PCSIR Laboratories ComplexKarachi 75280Pakistan

This study is theﬁrst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical *** outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the ***-ﬁve soil samples were collected,mainly from the arable land of the Porali *** drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric ***-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial *** granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt *** indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of *** indices reﬂect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr *** of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the *** correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type *** may result in the undesirable accumulation of certain trace elements which adversely affects crops.

关键词： Weathering indices Pollution indices Accumulation Repercussions Trace elements Multivariate analyses Porali Plain Balochistan

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Comparison of methods for deriving phenotypes from incomplete observation data with an application to age at puberty in dairy cattle

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Journal of Animal Science and Biotechnology 2024年第2期15卷 535-545页

作者： Melissa A.Stephen Chris R.Burke Jennie E.Pryce Nicole M.Steele Peter R.Amer Susanne Meier Claire V.C.Phyn Dorian J.Garrick DairyNZ Ltd 605 Ruakura RoadHamilton 3240New Zealand AL Rae centre for Genetics and Breeding-Massey University RuakuraHamilton 3214New Zealand Agriculture Victoria Research AgriBioCentre for AgriBioscienceBundooraVictoria 3083Australia School of applied Systems biology La Trobe UniversityBundooraVictoria 3083Australia AbacusBio DunedinNew Zealand

Background Many phenotypes in animal breeding are derived from incomplete measures,especially if they are challenging or expensive to measure *** include time-dependent traits such as reproductive status,or *** measures for these traits result in phenotypes that are subject to left-,interval-and rightcensoring,where phenotypes are only known to fall below an upper bound,between a lower and upper bound,or above a lower bound *** we compare three methods for deriving phenotypes from incomplete data using age at first elevation(>1 ng/mL)in blood plasma progesterone(AGEP4),which generally coincides with onset of puberty,as an example *** We produced AGEP4 phenotypes from three blood samples collected at about 30-day intervals from approximately 5,000 Holstein–Friesian or Holstein–Friesian×Jersey cross-bred dairy heifers managed in 54 seasonal-calving,pasture-based herds in New *** used these actual data to simulate 7 different visit scenarios,increasing the extent of censoring by disregarding data from one or two of the three *** methods for deriving phenotypes from these data were explored:1)ordinal categorical variables which were analysed using categorical threshold analysis;2)continuous variables,with a penalty of 31 d assigned to right-censored phenotypes;and 3)continuous variables,sampled from within a lower and upper bound using a data augmentation *** Credibility intervals for heritability estimations overlapped across all methods and visit scenarios,but estimated heritabilities tended to be higher when left censoring was *** sires with at least 5 daughters,the correlations between estimated breeding values(EBVs)from our three-visit scenario and each reduced data scenario varied by method,ranging from 0.65 to *** estimated breed effects also varied by method,but breed differences were smaller as phenotype censoring *** Our results indicate that using

关键词： Cattle Gibbs sampler Markov-chain Monte Carlo(MCMC) Puberty

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Equilibrium Arrivals to Preemptive Queueing System with Fixed and Random Population Size

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Journal of the Operations Research Society of China 2024年第1期12卷 77-92页

作者： Julia Chirkova Vladimir Mazalov Institute of applied Mathematical Research Karelian Research Centre of RASPetrozavodsk185910Russia School of Mathematics and Statistics Qingdao UniversityQingdao266071ShandongChina

A single-server queueing system with preemptive access is *** customer has one attempt to enter the system at its working interval[0,T].As soon as the customer request enters the system,the server immediately starts the *** when the next request arrives in the system,the previous one leaves the system even he has not finished his service *** study a non-cooperative game in which the customers wish to maximize their probability of obtaining service within a certain period of *** characterize the Nash equilibrium and the price of anarchy,which is defined as the ratio between the optimal and equilibrium social *** models are *** the first model the number of players is fixed,while in the second it is random and obeys the Poisson *** demonstrate that there exists a unique symmetric equilibrium for both ***,we calculate the price of anarchy for both models and show that the price of anarchy is not monotone with respect to the number of customers.

关键词： Service system Preemptive priorities Strategic users Random number of players Optimal arrivals Kolmogorov backward equations Nash equilibrium Price of anarchy

Precise immobilization of metal single atoms into a porphyrinic metal-organic framework for an efficient alkene hydrosilylation

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Nano Research 2024年第7期17卷 5914-5921页

作者： Chun-Ying Chen Qi-Jie Mo Fu-Zhen Li Hai-Li Song Li Zhang MOE Laboratory of Bioinorganic and synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

Competitive Resource Allocation Among Urban Congestion Areas in a Modern Big City

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Journal of the Operations Research Society of China 2024年第1期12卷 133-153页

作者： Alexander Krylatov Anastasiya Raevskaya Institute of applied Mathematical Research of the Karelian Research centre of the Russian Academy of Sciences Petrozavodsk185910Russia Saint Petersburg State University Saint Petersburg199034Russia

The continuing growth of modern big cities leads to their spatial expansion and the emergence of new road connections and urban *** where large transportation flows of pedestrians,passengers,and drivers come together create demand points,which attract business companies that strive to allocate their resources in the most sought-after ***,the law of supply and demand restrains companies from allocating all their resources solely in the most popular congestion areas since the more valuable an urban area,the higher the cost to be paid for a resource unit allocation *** a result,companies act in a non-cooperative manner and try to minimize their own overall costs when allocating resources across available commercial areas in a big ***-cooperative behavior of companies leads to the problem of Nash equilibrium search in the game of competing *** this paper,we study the corresponding resource allocation game under affine cost functions and obtain Nash equilibrium strategies in explicit *** findings allow us to develop a simple procedure for computing Nash equilibria in the game of companies allocating their resources among urban congestion *** computational study demonstrates the dependence of the average price for resource allocation on the number of players and their resource *** outcome of the paper contributes to flow theory and seems to be fresh and useful for managers.

关键词： Resource allocation Nash equilibrium Affine costs

Slow magnetic relaxation and photoluminescence behaviors of dilanthanide complexes bearing N_(8)O_(2)donor macrocyclic ligand

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Journal of Rare Earths 2024年第7期42卷 1298-1303,I0004页

作者： Pei-Yu Liao Yu-Quan Qi Zhen Li Jian-Hua Jia Ming-Liang Tong Key Laboratory of Bioinorganic and synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou510006China

On account of the complicated magnetic exchange interactions between lanthanide ions,binuclear lanthanide complexes have broad application prospect in the field of single-molecule ***,it is necessary to develop reasonable bridging ligands to manipulate the directional assembly of binuclear lanthanide ***,we selected the macrocyclic ligand L^(N_(8)O_(2))to build up two new dilanthanide complexes[Ln_(2)(LN_(8)O_(2))(OpyO)_(2)(H_(2)O)2](NO_(3))_(2)(1-Ln,Ln=Dy,Tb;LN_(8)O_(2)=hexamethyl-tetraaza-dioxe-dipyrazolacycloicosaphane-2,9,12,19-tetraene;OpyOH=2-pyridinol-1-oxide).Dynamic magnetic studies show that 1-Dy exhibits slow relaxation behavior under a 1 kOe applied *** fitting analysis of relaxation times gives the effective energy barrier of 38.2 cm^(−1),and reveals that the slow magnetic relaxation behavior is dominated by the Orbach and Raman ***-resolution luminescence emission spectrum indicates the energy gap of 36.8 cm^(−1)between the ground state and the first excited state,consistent with the magnetic measurement results.1-Tb exhibits brilliant characteristic green light emission under UV light *** absolute quantum yield of 1-Tb is 44.8%,and its first-order fitted decay lifetime is 779.21μs at room *** study provides the way for directional construction of high-performance molecular materials with magnetic and optical dual-function.

关键词： Dilanthanide complexes Single-molecule magnets Macrocyclic ligand Photoluminescence behavior Rare earths

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