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Amino Acid Transporter OsAAP18 Modulates Nitrogen Allocation to Boost Yield and Grain Quality in Rice
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作者 HE Chongchong YANG Xiaochuan +6 位作者 ZHANG Jie WU Wenhao WANG Chuanbo CHEN Wenbo WU Bowen HUANG Weiting FANG Zhongming 《Rice science》 2026年第2期151-154,I0028-I0040,共17页
Synergistically improving the yield and grain quality of rice remains a major breeding challenge.Amino acid transporters play key roles in regulating plant growth and development,but their mechanisms in synergisticall... Synergistically improving the yield and grain quality of rice remains a major breeding challenge.Amino acid transporters play key roles in regulating plant growth and development,but their mechanisms in synergistically regulating yield and quality remain unclear.Here,we report that the plasma membrane-localized transporter OsAAP18,which is more highly expressed in indica than japonica rice,positively correlates with tiller number and yield but negatively with grain width.OsAAP18 transports eight amino acids,including asparagine(Asn),proline(Pro),leucine(Leu),and valine(Val).Its overexpression increases yield through enhanced tillering and grain number per panicle while also improving rice processing and cooking quality.Transcriptome analysis showed that OsAAP18 coordinates grain development and quality formation by regulating the expression of key genes involved in starch and sucrose metabolism,nitrogen metabolism,and plant hormone signaling pathways.These findings establish OsAAP18 as a dual-function regulator that synergistically enhances yield and quality,offering a promising target for rice breeding. 展开更多
关键词 plasma membrane localized transporter acid transporters nitrogen allocation transports eight amino acidsi OSAAP YIELD grain quality rice breeding
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Research on heuristic approximation algorithm of the densest k-subgraph discovery in large-scale dynamic graphs
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作者 HAN Tao TIAN Yuxi +1 位作者 ZHAO Jianwei WANG Senzhang 《Journal of Southeast University(English Edition)》 2026年第1期74-79,共6页
To address the issue that static densest subgraph mining algorithms often exhibit low efficiency when handling large scale dynamic graphs,this paper proposes a heuristic approximation algorithm.The algorithm approxima... To address the issue that static densest subgraph mining algorithms often exhibit low efficiency when handling large scale dynamic graphs,this paper proposes a heuristic approximation algorithm.The algorithm approximates the densest k-subgraphs of the entire graph through four steps:partitioning the large-scale dynamic graph,constructing a partial set of the densest k-subgraphs,heuristically merging the subgraph sets,and finally extracting the densest k-subgraphs.This approach significantly reduces the computational time for large-scale dynamic graphs while simultaneously improving the quality of the resulting subgraphs.This algorithm is applicable to various definitions of“density”and can accommodate diverse requirements on the number of edges.When integrated with existing static densest subgraph detection algorithms,it achieves scalability and computational efficiency.Theoretical analysis demonstrates that the optimal density of the densest k-subgraphs extracted by the proposed algorithm reaches 0.9.To evaluate the performance of the algorithm,experiments were conducted on four billion-scale datasets:Friendster,Orkut,YouTube,and DBLP.The results indicate that the proposed algorithm outperforms static methods in both runtime efficiency and subgraph quality on large-scale dynamic graphs. 展开更多
关键词 the densest k-subgraph FEATURES heuristic approximation algorithm optimal density
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SsBMR1 as a putative ABC transporter is required for pathogenesis by promoting antioxidant export and antifungal resistance in Sclerotinia sclerotiorum
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作者 Yijuan Ding Yaru Chai +5 位作者 Sen Li Zhaohui Wu Minghong Zou Ling Zhang Rana Kusum Wei Qian 《Journal of Integrative Agriculture》 2026年第1期166-179,共14页
The plant pathogenic fungus Sclerotinia sclerotiorum is the causative agent of Sclerotinia stem rot(SSR)disease in most dicotyledons.Among the various proteins involved in drug efflux or substance transport,ATP-bindin... The plant pathogenic fungus Sclerotinia sclerotiorum is the causative agent of Sclerotinia stem rot(SSR)disease in most dicotyledons.Among the various proteins involved in drug efflux or substance transport,ATP-binding cassette(ABC)transporters constitute a superfamily of membrane-bound proteins that may play a crucial role in the survival of S.sclerotiorum.However,the expression patterns and functions of ABC transporter genes in S.sclerotiorum remain largely uncharacterized.This study characterized a highly expressed S.sclerotiorum ABC transporter gene during inoculation on host plants,Ss BMR1.Silencing Ss BMR1 resulted in a significant reduction in hyphal growth,infection cushion development,sclerotia formation,and virulence.Moreover,host-induced gene silencing(HIGS)of Ss BMR1 significantly enhanced plant resistance.Transcriptome and metabolomics analyses suggested that Ss BMR1 is involved in antioxidant and toxin transport,thereby influencing fungal defense and cell rescue mechanisms.In comparison to the wild-type strain,Ss BMR1 gene-silenced transformants exhibited a diminished response to extracellar oxidative stress and a decreased exporting of antioxidant glutathione.Tolerance assays further demonstrated the crucial role of Ss BMR1 in conferring resistance to the plant antifungal substances,camalexin and brassinin,as well as certain fungicides.Furthermore,Ss BMR1 gene-silenced transformants showed enhanced repression on virulence when sprayed with camalexin and brassinin on the leaves.Thus,Ss BMR1 likely contributes to virulence by facilitating the export of antioxidant and providing resistance against antifungal agents.The findings of this study provide valuable insights that could contribute to the development of novel management techniques for SSR. 展开更多
关键词 ABC transporter antifungal resistance GLUTATHIONE PATHOGENESIS Sclerotinia sclerotiorum
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Nutrient transporters in broiler chickens:intestinal gene expression profiles,functional roles,and influencing factors
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作者 Vahideh Shay Sadr Jose A.Quinteros +1 位作者 Sonia Yun Liu Reza Barekatain 《Journal of Animal Science and Biotechnology》 2026年第2期591-612,共22页
The primary role of the gastrointestinal tract in broiler chickens is nutrient assimilation,with transporter proteins facilitating the uptake of amino acids,peptides,monosaccharides,fatty acids,and minerals across the... The primary role of the gastrointestinal tract in broiler chickens is nutrient assimilation,with transporter proteins facilitating the uptake of amino acids,peptides,monosaccharides,fatty acids,and minerals across the intestinal epithelium.Among these nutrient transporters,members of the solute carrier family are particularly important,and gene expression analyses targeting these transporters have provided informative insights into how birds adapt to diverse dietary,environmental,and physiological challenges to maintain nutrient homeostasis.These transporters are expressed either at the brush border membrane,where they facilitate the absorption of nutrients from the gut lumen into enterocytes,or at the basolateral membrane,where they mediate the transfer of nutrients from the enterocytes into the bloodstream.The expression of these transporters is influenced by a range of factors,including bird age,sex,intestinal segment,dietary substrate availability and source,as well as external stressors such as heat stress and pathogen exposure.While upregulation of transporter genes often suggests an enhanced capacity for nutrient uptake,it does not always correlate with improved growth performance,due to compensatory physiological responses and fluctuations in nutrient bioavailability.Understanding the regulation and functional dynamics of nutrient transporters presents valuable opportunities to develop targeted dietary and management strategies aimed at optimizing nutrient utilization and improving bird performance.This review summarizes current knowledge on the classification,function,and regulation of key nutrient transporters in broilers,highlights factors influencing their expression,and explores their implications for nutrition and production efficiency. 展开更多
关键词 Broiler chickens Gene expression Growth performance Nutrient homeostasis Nutrient transporters
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NRAMPs:Versatile Transporters Involved in Metal Ion Homeostasis and Their Applications in Rice Breeding
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作者 HUANG Qina WU Lijuan +4 位作者 JIANG Hongrui HE Yan LIU Song YANG Changdeng LIANG Yan 《Rice science》 2026年第1期39-58,I0046,共21页
The NRAMP(natural resistance-associated macrophage protein)family plays a pivotal role in metal ion transport,regulating both essential micronutrient uptake and toxic heavy metal accumulation in plants.In rice(Oryza s... The NRAMP(natural resistance-associated macrophage protein)family plays a pivotal role in metal ion transport,regulating both essential micronutrient uptake and toxic heavy metal accumulation in plants.In rice(Oryza sativa),OsNRAMP transporters critically influence metal homeostasis,stress adaptation,and grain safety.Among them,OsNRAMP5 serves as a major entry point for cadmium(Cd)and manganese(Mn)uptake,making it a prime target for low-Cd rice breeding.However,knockout of OsNRAMP5 leads to severe Mn deficiency,highlighting the need for precise genetic modifications(e.g.,OsNRAMP5-Q337K),which reduce Cd accumulation while maintaining Mn nutrition.Additionally,OsNRAMP1 and OsNRAMP2 contribute to Cd translocation and plant immunity,whereas OsNRAMP3/4/6/7 participate in Mn,iron,and zinc distribution and stress responses.This review systematically summarizes the structural,functional,and regulatory mechanisms of OsNRAMPs,emphasizing their roles in metal transport,pathogen resistance,and abiotic stress adaptation.Furthermore,we discuss strategies for developing low-Cd rice varieties,including QTL-based breeding,CRISPR/Cas9-mediated gene editing,and multi-gene stacking approaches.Finally,we outline future research directions,such as structural engineering of metal-binding sites and field validation of engineered rice lines,to ensure sustainable rice production in heavy metal-contaminated soils. 展开更多
关键词 NRAMP transporter metal homeostasis cadmium regulatory network low-cadmium rice breeding
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ABCA5 lipid transporter is associated with a reduced risk of Parkinson’s disease
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作者 Jasmin Galper Nicolas Dzamko Woojin Scott Kim 《Neural Regeneration Research》 2026年第2期669-670,共2页
A key pathological feature of Parkinson’s disease(PD)is that lysosomes are overwhelmed with cellular materials that need to be degraded and cleared.While the build-up of protein is characteristic of neurodegenerative... A key pathological feature of Parkinson’s disease(PD)is that lysosomes are overwhelmed with cellular materials that need to be degraded and cleared.While the build-up of protein is characteristic of neurodegenerative diseases such as PD and Alzheimer’s disease(AD)and is thought to reflect lysosome dysfunction,lipid accumulation may also contribute to and be indicative of severe lysosomal dysfunction.Much is known about the detrimental effects of glucosylceramide accumulation in PD lysosomes. 展开更多
关键词 neurodegenerative diseases lipid transporter abca LYSOSOME protein build up Alzheimers disease cellular materials Parkinsons disease
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Impairment of hippocampal long-term potentiation by soluble amyloid-βoligomers is mediated by glutamate transporter 1 expressed in neurons
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作者 Shaomin Li Jianlin Wang +5 位作者 Qianqin Guo Yunxin Bai Wen Liu Kevin JHodgetts Paul ARosenberg Dennis J.Selkoe 《Neural Regeneration Research》 2026年第7期3171-3177,共7页
In Alzheimer’s disease,perturbations of glutamate neurotransmission lead to synaptic dysfunction and synapse loss.Several studies have used glutamate transport inhibitors to demonstrate that soluble oligomers of amyl... In Alzheimer’s disease,perturbations of glutamate neurotransmission lead to synaptic dysfunction and synapse loss.Several studies have used glutamate transport inhibitors to demonstrate that soluble oligomers of amyloid-βinduce synaptic dysfunction by interrupting glutamate uptake mediated by glutamate transporter 1,the major glutamate transporter in the brain.The cellular targets of the synaptic effects of soluble amyloid-βoligomers,including the nature of any interaction with glutamate transporter 1,remain ill-defined.We have generated a conditional glutamate transporter 1 knockout mouse to investigate cell-type specific functions of glutamate transporter 1.Field excitatory postsynaptic potentials were examined in the CA1 region of mouse hippocampal slices.We confirmed that hippocampal long-term potentiation impairment is induced by both soluble amyloid-β oligomers and glutamate uptake inhibitors.Amyloid-βoligomers,including those isolated directly from the cortex of patients with Alzheimer’s disease,failed to inhibit hippocampal long-term potentiation in neuronal glutamate transporter 1 but not astrocytic glutamate transporter 1 knockout mice.The masking or occlusion of the effect of soluble amyloid-β oligomers by knockout of glutamate transporter 1 in neurons suggests that the metabolic or signaling consequences of knockout of glutamate transporter 1 in neurons and amyloid-βoligomer inhibition of synaptic plasticity show epistasis and thus share a similar molecular pathway.To extend these observations,we tested the effects of other types of manipulation of glutamate homeostasis on synaptic plasticity and the pathophysiology of soluble amyloid-β oligomers.Ceftriaxone,which upregulates glutamate transporter 1 levels,among other effects,prevented the impairment of long-term potentiation by soluble amyloid-β oligomers.Collectively,our findings suggest that the effects of amyloid-βon synaptic function are highly dependent on glutamate reuptake homeostasis and that the disruption of synaptic function by soluble amyloid-β oligomers is mediated by pathways linked to neuronal,not astrocytic,glutamate transporter 1.The findings of this study highlight the translational potential of targeting neuronal glutamate transporter 1 to counteract amyloid-β-induced synaptic dysfunction in Alzheimer’s disease.By showing that glutamate transporter 1 upregulation(e.g.,via ceftriaxone)can prevent amyloid-β-related impairments,this research supports developing therapies aimed at modulating glutamate homeostasis to preserve synaptic function and combat cognitive decline in patients with Alzheimer’s disease. 展开更多
关键词 Alzheimer’s disease CEFTRIAXONE glutamate transporter 1 hippocampal synaptic plasticity long-term potentiation mitochondria PRESYNAPTIC soluble Aβoligomers
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Monte Carlo simulation of in-plane spin-polarized transport in GaAs/GaAlAs quantum well in the three-subband approximation 被引量:2
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作者 孔令刚 刘晓彦 +3 位作者 杜刚 王漪 康晋锋 韩汝琦 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第3期654-658,共5页
We develop a Monte Carlo (MC) tool incorporated with the three-subband approximation model to investigate the in-plane spln-polarized transport in GaAs/GaAlAs quantum well. Using the tool, the effects of the electro... We develop a Monte Carlo (MC) tool incorporated with the three-subband approximation model to investigate the in-plane spln-polarized transport in GaAs/GaAlAs quantum well. Using the tool, the effects of the electron occupation of higher subbands and the intersuhband scattering on the spin dephasing have been studied. Compared with the corresponding results of the simple one-snbband approximation model, the spin dephasing length is reduced four times under 0.125 kV/cm of driving electric field at 300K by the MC tool incorporated with the three-subband approximation model, indicating that the three-subbarld approximation model predicts significantly shorter spin dephasing length with temperature increasing. Our simulation results suggest that the effects of the electron occupation of higher subbands and the intersubband scattering on the spln-dependent transport of GaAs 2-dhuensional electron gas need to be considered when the driving electric field exceeds the moderate value and the lattice temperature is above 100K. The simulation by using the MC tool incorporated with the three-subband approximation model also indicates that, under a eertain driving electric field and lattice temperature, larger channel widths cause spins to be depolarized faster. Ranges of the three components of the spins are different for three different injected spin polarizations due to the anisotropy of spin-orbit interaction. 展开更多
关键词 Monte Carlo spin dephasing spin-polarized transport three-subband approximation model
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Application of homogenization techniques for inflow transport approximation on light water reactor analysis 被引量:2
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作者 Xiang Xiao Kan Wang +1 位作者 Tong-Rui Yang Yi-Xue Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第1期67-80,共14页
The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering effect.The prev... The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering effect.The previous inflow transport approximation is based on the moderator cross-section and normalized fission source,which is approximated using transport theory.Although the accuracy of reactivity is increased,the P0 flux moment has a large error in the Monte Carlo code.In this study,an improved inflow transport approximation was introduced with homogenization techniques,applying the homogenized cross-section and accurate fission source.The numerical results indicated that the improved inflow transport approximation can increase the P0 flux moment accuracy and maintain the reactivity calculation precision with the previous inflow transport approximation in typical LWR cases.In addition to this investigation,the improved inflow transport approximation is related to the temperature factors.The improved inflow transport approximation is flexible and accurate in the treatment of the anisotropic scattering effect,which can be directly used in the temperature-dependent nuclear data library. 展开更多
关键词 Inflow transport approximation Anisotropic scattering effect Homogenization techniques Light water reactor
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ATP-binding cassette (ABC) transporters: structures and roles in bacterial pathogenesis 被引量:2
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作者 Shu Sian HOW Sheila NATHAN +1 位作者 Su Datt LAM Sylvia CHIENG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第1期58-75,共18页
Adenosine triphosphate(ATP)-binding cassette(ABC)transporter systems are divided into importers and exporters that facilitate the movement of diverse substrate molecules across the lipid bilayer,against the concentrat... Adenosine triphosphate(ATP)-binding cassette(ABC)transporter systems are divided into importers and exporters that facilitate the movement of diverse substrate molecules across the lipid bilayer,against the concentration gradient.These transporters comprise two highly conserved nucleotide-binding domains(NBDs)and two transmembrane domains(TMDs).Unlike ABC exporters,prokaryotic ABC importers require an additional substrate-binding protein(SBP)as a recognition site for specific substrate translocation.The discovery of a large number of ABC systems in bacterial pathogens revealed that these transporters are crucial for the establishment of bacterial infections.The existing literature has highlighted the roles of ABC transporters in bacterial growth,pathogenesis,and virulence.These roles include importing essential nutrients required for a variety of cellular processes and exporting outer membrane-associated virulence factors and antimicrobial substances.This review outlines the general structures and classification of ABC systems to provide a comprehensive view of the activities and roles of ABC transporters associated with bacterial virulence and pathogenesis during infection. 展开更多
关键词 ATP-binding cassette(ABC)transporter Bacterial pathogenesis VIRULENCE
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Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior
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作者 Xirong Xu Shoumin Xuan +3 位作者 Shuai Chen Dan Liu Qian Xiao Jie Tu 《Neural Regeneration Research》 SCIE CAS 2025年第6期1721-1734,共14页
The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain functio... The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders. 展开更多
关键词 ANXIETY ASTROCYTES basolateral amygdala behavior dihydrokainic acid excitatory amino acid transporter 2 fiber photometry GLUTAMATE LDN-212320 transporter
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An Approximation Method for Singular Trudinger-Moser Inequality
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作者 ZHU Maochun XU Wenyan JIANG Rou 《应用数学》 北大核心 2025年第1期64-70,共7页
In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to... In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to the concentration level of singular Trudinger-Moser functional on the unit ball. 展开更多
关键词 Singular Trudinger-Moser inequality approximation functional Concentration level
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Genome-wide identifcation of sucrose transporter genes in Camellia oleifera and characterization of CoSUT4 被引量:1
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作者 Jing Zhou Bingshuai Du +4 位作者 Yibo Cao Kui Liu Zhihua Ye Yiming Huang Lingyun Zhang 《Journal of Integrative Agriculture》 2025年第9期3494-3510,共17页
Sucrose transporters(SUTs)play a crucial role in carbon allocation from the source leaf to the sink end,and the function of SUTs varies among family members.However,the genome-wide identifcation of the SUT superfamily... Sucrose transporters(SUTs)play a crucial role in carbon allocation from the source leaf to the sink end,and the function of SUTs varies among family members.However,the genome-wide identifcation of the SUT superfamily in Camellia oleifera is lacking,and their biological function remains elusive.In this study,four SUT genes-designated Co SUT1-4-were identifed in C.oleifera through a genome-wide analysis and classifed into three subfamilies.We used a combination of cis-acting elements analysis,mRNA quantifcation,histochemical analysis,and heterologous transformation to evaluate the expression profiles and functions of these SUTs.A key finding is that CoSUT4,localized on the plasma membrane,is highly expressed in mature leaves and the early stage of seed development in C.oleifera.In vitro culture of C.oleifera seed revealed the responsiveness of CoSUT4 to various exogenous hormones such as ABA and GA.CoSUT4 was able to restore the growth of the yeast strain SUSY7/ura3(a sucrose transport-defcient mutant)on sucrose-containing media and specifcally contributed to sucrose translocation and tissue growth in CoSUT4-overexpressed apple calli.In situ hybridization identifed chalazal nucellus and transfer cells as the action sites of CoSUT4 at the maternal-flial interface mediating sucrose transportation in oil tea seeds.CoSUT4 overexpression in Arabidopsis thaliana atsuc4 mutant restored the growth and seed yield defciencies of the mutant,leading to an increase in flled seeds and oil content.Additionally,CoSUT4 overexpression enhanced the drought and salt stress tolerance by augmenting sugar content.Overall,these fndings provide valuable insights into the function of SUTs and present promising candidates for the genetic enhancement of seed production in C.oleifera. 展开更多
关键词 Camellia oleifera sucrose transporter genome-wide analysis sugar accumulation abiotic stress
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Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons
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作者 AoJun Ren Jiang Yu +2 位作者 Jing Wang ZuZheng Chen XiaoMan Liu 《Earth and Planetary Physics》 EI CAS 2025年第1期159-170,共12页
Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous ... Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous quantitative analyses often simplified the chorus dispersion relation by using the cold plasma assumption.However,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic disturbances.We here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to 2018.The statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma density.The region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density decreases.In addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus waves.Compared with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those below.Furthermore,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density. 展开更多
关键词 chorus waves cold plasma approximation dispersion relations scattering rates
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Exceptional Set for Diophantine Approximation with Primes of Two Squares and Three Biquadrates
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作者 LIU Minmin ZHANG Min LI Jinjiang 《数学进展》 北大核心 2025年第1期18-36,共19页
Suppose thatλ_(1),λ_(2),λ_(3),λ_(4),λ_(5)are nonzero real numbers,not all of the same sign,andλ_(1)/λ_(2)is irrational and algebraic.Let V be a well-spaced sequence,δ>0.In this paper,it is proved that,for ... Suppose thatλ_(1),λ_(2),λ_(3),λ_(4),λ_(5)are nonzero real numbers,not all of the same sign,andλ_(1)/λ_(2)is irrational and algebraic.Let V be a well-spaced sequence,δ>0.In this paper,it is proved that,for anyε>0,the number of v∈V with v≤N such that the following inequality|λ_(1)p_(1)~2+λ_(2)p_(2)~2+λ_(3)p_(3)~4+λ_(4)p_(4)~4+λ_5p_5~4-v|<v^(-δ)has no solution in prime variables p_(1),p_(2),p_(3),p_(4),p_(5)does not exceed O(N^(29/32+2δ+ε)). 展开更多
关键词 Diophantine approximation exponential sum Davenport-Heilbronn method prime variable
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Smoluchowski-Kramers Approximation for Stochastic Differential Equations under Discretization
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作者 Li Ge 《应用概率统计》 北大核心 2025年第4期622-635,共14页
This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–M... This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–Maruyama discretization and derive its convergence rate.In particular,the solution of the discretized system converges to the solution of the first-order limit equation in the mean-square sense,and this convergence is independent of the order in which the mass parameterμand the step size h tend to zero. 展开更多
关键词 stochastic differential equations Smoluchowski-Kramers approximation driftimplicit Euler-Maruyama scheme convergence rate
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Stepwise superposition approximation approach for analytical solutions with non-zero initial concentration using existing solutions of zero initial concentration in contaminate transport
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作者 Hongtao Wang Rong Han Yan Zhao Wenjing Lu Yaxin Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第6期923-930,共8页
Analytical solutions for contaminant transport are widely used for both theoretical and practical purposes.However,many existing solutions are obtained subject to an initial condition of zero concentration,which is of... Analytical solutions for contaminant transport are widely used for both theoretical and practical purposes.However,many existing solutions are obtained subject to an initial condition of zero concentration,which is often unrealistic in many practical cases.This article proposed a stepwise superposition approximation approach to solve the non-zero initial concentration problem for first-type and third-type boundary conditions by using the existing zero initial concentration solution.Theoretical examples showed that the approach was highly efficient if a proper superposition scheme with relative concentration increments was constructed.The key parameter that controlled the convergence speed was the time increment(△t) multiplied by the rate constant(λ).The approach served also as an alternative way to make a convenient concentration calculation even if the non-zero initial concentration solution of a problem was known. 展开更多
关键词 analytical solution contaminate transport non-zero initial concentration superposition approximation relative concentration increment
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Heat transport of hybrid nanomaterial in an annulus with quadratic Boussinesq approximation 被引量:2
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作者 K.THRIVENI B.MAHANTHESH 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第6期885-900,共16页
The convective heat transfer of hybrid nanoliquids within a concentric annulus has wide engineering applications such as chemical industries, solar collectors, gas turbines, heat exchangers, nuclear reactors, and elec... The convective heat transfer of hybrid nanoliquids within a concentric annulus has wide engineering applications such as chemical industries, solar collectors, gas turbines, heat exchangers, nuclear reactors, and electronic component cooling due to their high heat transport rate. Hence, in this study, the characteristics of the heat transport mechanism in an annulus filled with the Ag-MgO/H_2O hybrid nanoliquid under the influence of quadratic thermal radiation and quadratic convection are analyzed. The nonuniform heat source/sink and induced magnetic field mechanisms are used to govern the basic equations concerning the transport of the composite nanoliquid. The dependency of the Nusselt number on the effective parameters(thermal radiation, nonlinear convection,and temperature-dependent heat source/sink parameter) is examined through sensitivity analyses based on the response surface methodology(RSM) and the face-centered central composite design(CCD). The heat transport of the composite nanoliquid for the spacerelated heat source/sink is observed to be higher than that for the temperature-related heat source/sink. The mechanisms of quadratic convection and quadratic thermal radiation are favorable for the momentum of the nanoliquid. The heat transport rate is more sensitive towards quadratic thermal radiation. 展开更多
关键词 quadratic Boussinesq approximation non-uniform heat source/sink hybrid nanoliquid response surface methodology(RSM) ANNULUS sensitivity analysis
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Intestinal transporters and oral absorption enhancing strategies based on these transporters
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作者 Ju Wang Yongbing Sun +3 位作者 Lingbang Meng Jianfang Feng Meng Cheng Liangxing Tu 《Chinese Chemical Letters》 2025年第5期82-98,共17页
Utilizing transporter-mediated drug delivery to achieve effective oral absorption emerges as a promising strategy.Researchers have been concentrated on discovering solutions to the issues of low solubility and poor pe... Utilizing transporter-mediated drug delivery to achieve effective oral absorption emerges as a promising strategy.Researchers have been concentrated on discovering solutions to the issues of low solubility and poor permeability of insoluble drugs,whereas,current reports have revealed that drug transporter proteins are abundantly expressed in the mucosa of intestinal epithelial cells,and that their mediated drug absorption effectively improved the bioavailability of orally administered drugs.There are two main categories based on the transporter mechanism,which include the family of ATP-binding cassette(ABC)transporters with efflux effects that reduce drug bioavailability and the family of solute carriers(SLC)transporters with uptake effects that promote drug absorption,respectively.Thus,we review studies of intestinal transporter-mediated delivery of drugs to enhance oral absorption,including the types of intestinal transporters,distribution characteristics,and strategies for enhancing oral absorption using transporter-mediated drug delivery systems are summarized,with the aim of providing important theoretical references for the development of intestinal-targeted delivery system. 展开更多
关键词 Intestinal transporter BIOAVAILABILITY Oral delivery Intestinal absorption SLC transporters ABC transporters
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Analysis of Sulfate Transporter Gene Family 3 in Rice
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作者 LI Ruili XU Zhuang +4 位作者 WANG Wanxia WANG Huang ZHAO Hongyu XU Lei YI Keke 《Rice science》 2025年第4期449-452,I0011-I0017,共11页
Sulfate transporters(SULTRs)facilitate sulfate uptake and transport in plants.In plants,SULTRs can be classified into four distinct functional groups,among which SULTR3 members are the least characterized,and their fu... Sulfate transporters(SULTRs)facilitate sulfate uptake and transport in plants.In plants,SULTRs can be classified into four distinct functional groups,among which SULTR3 members are the least characterized,and their functions have not yet been confirmed,especially for SULTR3 in rice.In this study,we analyzed the expression patterns,subcellular localization,and inorganic phosphate(Pi)transporter activity of SULTR3 proteins in yeast.Except for OsSULTR3.4,which localized to the plasma membrane,other OsSULTR3 members were localized to the endoplasmic reticulum(ER)membrane in rice protoplast cells. 展开更多
关键词 sulfate transporters sultrs facilitate inorganic phosphate transporter activity plasma membraneother sulfate transporters RICE YEAST expression patternssubcellular sultr
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