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Recently, attention mechanism and derived models have gained significant traction in drug development due to their outstanding performance and interpretability in handling complex data structures. This review offers an in-depth exploration of the principles underlying attention-based models and their advantages in drug discovery. We further elaborate on their applications in various aspects of drug development, from molecular screening and target binding to property prediction and molecule generation. Finally, we discuss the current challenges faced in the application of attention mechanisms and Artificial Intelligence technologies, including data quality, model interpretability and computational resource constraints, along with future directions for research. Given the accelerating pace of technological advancement, we believe that attention-based models will have an increasingly prominent role in future drug discovery. We anticipate that these models will usher in revolutionary breakthroughs in the pharmaceutical domain, significantly accelerating the pace of drug development.
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Inteligência Artificial , Descoberta de Drogas , Desenvolvimento de Medicamentos , Confiabilidade dos DadosRESUMO
The discovery of superconductivity in infinite-layer nickelates established another category of unconventional superconductors that shares structural and electronic similarities with cuprates. However, key issues of the superconducting pairing symmetry, gap amplitude and superconducting fluctuations are yet to be addressed. Here we utilize static and ultrafast terahertz spectroscopy to address these. We demonstrate that the equilibrium terahertz conductivity and non-equilibrium terahertz responses of an optimally Sr-doped nickelate film (superconducting transition temperature of Tc = 17 K) are in line with the electrodynamics of d-wave superconductivity in the dirty limit. The gap-to-Tc ratio (2Δ/kBTc) is found to be 3.4, indicating that the superconductivity falls in the weak coupling regime. In addition, we observed substantial superconducting fluctuations near Tc that do not extend into the deep normal state as the optimally hole-doped cuprates do. Our results support a d-wave system that closely resembles the electron-doped cuprates.
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Electrocatalysis is considered promising in renewable energy conversion and storage, yet numerous efforts rely on catalyst design to advance catalytic activity. Herein, a hydrodynamic single-particle electrocatalysis methodology is developed by integrating collision electrochemistry and microfluidics to improve the activity of an electrocatalysis system. As a proof-of-concept, hydrogen evolution reaction (HER) is electrocatalyzed by individual palladium nanoparticles (Pd NPs), with the development of microchannel-based ultramicroelectrodes. The controlled laminar flow enables the precise delivery of Pd NPs to the electrode-electrolyte interface one by one. Compared to the diffusion condition, hydrodynamic collision improves the number of active sites on a given electrode by 2 orders of magnitude. Furthermore, forced convection enables the enhancement of proton mass transport, thereby increasing the electrocatalytic activity of each single Pd NP. It turns out that the improvement in mass transport increases the reaction rate of HER at individual Pd NPs, thus a phase transition without requiring a high overpotential. This study provides new avenues for enhancing electrocatalytic activity by altering operating conditions, beyond material design limitations.
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Measurement of infrared spectroscopy has emerged as a significant challenge for carbon materials due to the sampling problem. To overcome this issue, in this work, we performed measurements of IR spectra for carbon materials including C60, C70, diamond powders, graphene, and carbon nanotubes (CNTs) using the photoacoustic spectroscopy (PAS) technique; for comparison, the vibrational patterns of these materials were also studied with a conventional transmission method, diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, or Raman spectroscopy. We found that the IR photoacoustic spectroscopy (IR-PAS) scheme worked successfully for these carbon materials, offering advantages in sampling. Interestingly, the profiles of IR-PAS spectra for graphene and CNTs exhibit negative bands using carbon black as the reference; the negative spectral information may provide valuable knowledge about the storage energy, production, structure, defect, or impurity of graphene and CNTs. Thus, this approach may open a new avenue for analyzing carbon materials.
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The abnormal activation of Cullin RING E3 Ligases (CRLs) is closely associated with the occurrence and development of various cancers. Targeting the neddylation pathway represents an effective approach for cancer treatment. In this work, we reported that WS-299, structurally featuring a coumarin moiety attached to the triazolopyrimidine, exhibited excellent anti-proliferative activity in MGC-803 and HGC-27 cells. WS-299 exerted potent anticancer effects by inhibiting clone formation, EdU incorporation and inducing cell cycle arrest. WS-299 inhibited CUL3/5 neddylation and caused an obvious accumulation of Nrf2 and NOXA, substrates of CRL3 and CRL5, respectively. Biochemical studies showed that WS-299 inhibited CUL3 neddylation by inhibiting RBX1-UBE2M interaction. The anti-proliferative effect of WS-299 was mainly induced by NOXA-mediated apoptosis. Of note, Nrf2 attenuated WS-299-induced reactive oxygen species (ROS) levels. Furthermore, Nrf2 accumulation also had an antagonistic effect on NOXA-induced apoptosis. Therefore, WS-299 and siNrf2 synergistically increased ROS levels, apoptotic cells and suppressed tumor growth in vivo. Taken together, our research clarified the anti-cancer mechanisms of WS-299 through targeting the RBX1-UBE2M protein-protein interaction and inhibiting the neddylation modification of CUL3 and CUL5. More importantly, our studies also demonstrated that combination of WS-299 with shNrf2 could be an effective strategy for treating gastric cancers.
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Fator 2 Relacionado a NF-E2 , Neoplasias Gástricas , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Pontos de Checagem do Ciclo Celular , Estresse Oxidativo , Proteínas de Transporte/metabolismo , Proteínas Culina/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismoRESUMO
BACKGROUND: An accessory extreme far anteromedial portal can improve visualisation and ease inferior leaf meniscectomy in patients with lateral meniscal anterior horn horizontal tears. However, the therapeutic outcomes of adding an accessory extreme far anteromedial portal remain unclear. This study aimed to evaluate the clinical efficacy of adding an accessory extreme far anteromedial portal for treating lateral meniscal horizontal tears involving the anterior horns. METHODS: This retrospective study included 101 patients with anterior horn involvement in lateral meniscal horizontal tears who underwent arthroscopic unstable inferior leaf meniscectomy between January 2016 and December 2020. The pathologies were diagnosed using physical examinations and magnetic resonance imaging. The anterior horn involved in the lateral meniscal horizontal tears was treated using inferior leaf meniscectomy. The primary endpoints were changes in the visual analogue scale, Lysholm, International Knee Documentation Committee, and Tegner scores at the final follow-up. The secondary endpoint was meniscal cure rate at 3 months postoperatively. The preoperative and postoperative functional scores were compared. The occurrence of complications was recorded. RESULTS: All patients were followed up for an average of 4.9 ± 1.2 years (range 2.3-7.5 years). After 4 months, none of the patients experienced pain, weakness, instability, or tenderness in the lateral joint line, achieving an imaging cure rate of 98%. At the final follow-up, significant postoperative improvements were observed in the average values of the visual analogue scale score (3.5 ± 0.7 vs. 0.7 ± 0.6), Lysholm score (62.7 ± 4.4 vs. 91.8 ± 3.1), International Knee Documentation Committee score (61.9 ± 3.7 vs. 91.7 ± 9.5), and Tegner score (2.0 ± 0.7 vs. 6.1 ± 0.7). Excellent Lysholm scores were obtained in 81 patients, and good outcomes were obtained in 18 patients, with an excellent-to-good rate of 98.0%. CONCLUSIONS: Inferior leaf resection via the accessory far anteromedial portal is a safe treatment option for the involved anterior horn in lateral meniscal horizontal tears. This approach enhances visibility and facilitates surgical procedures, with minimal complications.
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Meniscectomia , Meniscos Tibiais , Animais , Humanos , Meniscos Tibiais/diagnóstico por imagem , Meniscos Tibiais/cirurgia , Estudos Retrospectivos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , ArtroscopiaRESUMO
Extreme ultraviolet (EUV) radiation with wavelengths of 10-121 nm has drawn considerable attention recently for its use in photolithography to fabricate nanoelectronic chips. This study demonstrates, for the first time, fluorescent nanodiamonds (FNDs) with nitrogen-vacancy (NV) centers as scintillators to image and characterize EUV radiations. The FNDs employed are â¼100 nm in size; they form a uniform and stable thin film on an indium-tin-oxide-coated slide by electrospray deposition. The film is nonhygroscopic and photostable and can emit bright red fluorescence from NV0 centers when excited by EUV light. An FND-based imaging device has been developed and applied for beam diagnostics of 50 nm and 13.5 nm synchrotron radiations, achieving a spatial resolution of 30 µm using a film of â¼1 µm thickness. The noise equivalent power density is 29 µW/(cm2 Hz1/2) for the 13.5 nm radiation. The method is generally applicable to imaging EUV radiation from different sources.
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Pollen cells require large amounts of sugars from the anther to support their development, which is critical for plant sexual reproduction and crop yield. Sugars Will Eventually be Exported Transporters (SWEETs) have been shown to play an important role in the apoplasmic unloading of sugars from anther tissues into symplasmically isolated developing pollen cells and thereby affect the sugar supply for pollen development. However, among the 17 CsSWEET genes identified in the cucumber (Cucumis sativus L.) genome, the CsSWEET gene involved in this process has not been identified. Here, a member of the SWEET gene family, CsSWEET5a, was identified and characterized. The quantitative real-time PCR and ß-glucuronidase expression analysis revealed that CsSWEET5a is highly expressed in the anthers and pollen cells of male cucumber flowers from the microsporocyte stage (stage 9) to the mature pollen stage (stage 12). Its subcellular localization indicated that the CsSWEET5a protein is localized to the plasma membrane. The heterologous expression assays in yeast demonstrated that CsSWEET5a encodes a hexose transporter that can complement both glucose and fructose transport deficiencies. CsSWEET5a can significantly rescue the pollen viability and fertility of atsweet8 mutant Arabidopsis plants. The possible role of CsSWEET5a in supplying hexose to developing pollen cells via the apoplast is also discussed.
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Arabidopsis , Cucumis sativus , Arabidopsis/genética , Arabidopsis/metabolismo , Cucumis sativus/metabolismo , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Hexoses/metabolismo , Pólen/genética , Pólen/metabolismo , Saccharomyces cerevisiae/metabolismo , Fertilidade/genética , Regulação da Expressão Gênica de PlantasRESUMO
The microtubule-associated protein tau participates in neurotransmission regulation via its interaction with synaptic vesicles (SVs). The precise nature and mechanics of tau's engagement with SVs, especially regarding alterations in vesicle dynamics, remain a matter of discussion. We report an electrochemical method using a synapse-mimicking nanopipette to monitor vesicle dynamics induced by tau. A model vesicle of ~30â nm is confined within a lipid-modified nanopipette orifice with a comparable diameter to mimic the synaptic lipid environment. Both tau and phosphorylated tau (p-tau) present two-state dynamic behavior in this biomimetic system, showing typical ionic current oscillation, induced by lipid-tau interaction. The results indicate that p-tau has a stronger affinity to the lipid vesicles in the confined environment, blocking the vesicle movement to a higher degree. Taken together, this method bridges a gap for sensing synaptic vesicle dynamics in a confined lipid environment, mimicking vesicle movement near the synaptic membrane. These findings contribute to understanding how different types of tau protein regulate synaptic vesicle motility and to underlying its functional and pathological behaviours in disease.
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Light-induced ferroelectricity in quantum paraelectrics is a new avenue of achieving dynamic stabilization of hidden orders in quantum materials. In this Letter, we explore the possibility of driving a transient ferroelectric phase in the quantum paraelectric KTaO_{3} via intense terahertz excitation of the soft mode. We observe a long-lived relaxation in the terahertz-driven second harmonic generation (SHG) signal that lasts up to 20 ps at 10 K, which may be attributed to light-induced ferroelectricity. Through analyzing the terahertz-induced coherent soft-mode oscillation and finding its hardening with fluence well described by a single-well potential, we demonstrate that intense terahertz pulses up to 500 kV/cm cannot drive a global ferroelectric phase in KTaO_{3}. Instead, we find the unusual long-lived relaxation of the SHG signal comes from a terahertz-driven moderate dipolar correlation between the defect-induced local polar structures. We discuss the impact of our findings on current investigations of the terahertz-induced ferroelectric phase in quantum paraelectrics.
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Netrin-4, a member of the Netrins family, is an important secreted protein that plays a role in axonal outgrowth and migration orientation. It was initially described that Netrin-4 had a high correlation with the laminin ß-chain and promoted the growth of neurites in cultured olfactory bulb explants. Subsequently, it was discovered that Netrin-4 is involved in regulating various physiological processes, including angiogenesis, the occurrence and metastasis of various tumors, and the development of the kidney and alveoli. This paper reviews the current research on Netrin-4 since its discovery and provides a theoretical basis for further research on the biological characteristics of Netrin-4. Effects of Netrin-4. Netrin-4 regulates axon guidance, angiogenesis and the development of various tumors.
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Neoplasias , Receptores de Superfície Celular , Humanos , Receptores de Superfície Celular/metabolismo , Fatores de Crescimento Neural/farmacologia , Fatores de Crescimento Neural/metabolismo , Orientação de Axônios , Proteínas Supressoras de Tumor/metabolismo , Netrinas , Axônios/metabolismoRESUMO
KEY MESSAGE: Seventy-three QTL related to grain color and tannin content were identified in Chinese sorghum accessions, and a new recessive allelic variant of TAN2 gene was discovered. Sorghum is mainly used for brewing distilled liquors in China. Since grain tannins play an important role in liquor brewing, accurately understanding the relationship between grain color and tannin content can provide basis for selection standards of tannin sorghum. We resequenced a panel of 242 Chinese sorghum accessions and performed population structure and genome-wide association study (GWAS) to identify quantitative trait locus (QTL) affecting pericarp color, testa pigment, and tannin content. Phylogenetic analysis, principal component analysis (PCA), and admixture model were used to infer population structure. Two distinct genetic sub-populations were identified according to their corresponding northern and southern geographic origin. To investigate the genetic basis of natural variation in sorghum grain color, GWAS with 2,760,264 SNPs was conducted in four environments using multiple models (Blink, FarmCPU, GLM, and MLM). Seventy-three QTL were identified to be associated for the color of exocarp, mesocarp, testa, and tannin content on all chromosomes except chromosome 5, of which 47 might be novel QTL. Some important QTL were found to colocalize with orthologous genes in the flavonoid biosynthetic pathway from other plants, including orthologous of Arabidopsis (Arabidopsis thaliana) TT2, TT7, TT12, TT16 and AT5G41220 (GST), as well as orthologous of rice (Oryza sativa) MYB61 and OsbHLH025. Our investigation of the variation in grain color and tannin content in Chinese sorghum germplasm may help guide future sorghum breeding for liquor brewing.
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Estudo de Associação Genômica Ampla , Sorghum , Grão Comestível/genética , Filogenia , Melhoramento Vegetal , Sorghum/genética , Taninos/análiseRESUMO
Extensive studies of the tumor microenvironment (TME) in the last decade have reformed the view of cancer as a tumor cell-centric disease. The tumor microenvironment, especially termed the "seed and soil" theory, has emerged as the key determinant in cancer development and therapeutic resistance. The TME mainly consists of tumor cells, stromal cells such as fibroblasts, immune cells, and other noncellular components. Within the TME, intimate communications among these components largely determine the fate of the tumor. The pivotal roles of the stroma, especially cancer-associated fibroblasts (CAFs), the most common component within the TME, have been revealed in tumorigenesis, tumor progression, therapeutic response, and tumor immunity. A better understanding of the function of the TME sheds light on tumor therapy. In this review, we summarize the emerging understanding of stromal factors, especially CAFs, in cancer progression, drug resistance, and tumor immunity with an emphasis on their functions in epigenetic regulation. Moreover, the importance of epigenetic regulation in reshaping the TME and the basic biological principles underpinning the synergy between epigenetic therapy and immunotherapy will be further discussed.
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Fibroblastos Associados a Câncer , Neoplasias , Humanos , Epigênese Genética , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Carcinogênese , Fibroblastos , Fibroblastos Associados a Câncer/patologia , Microambiente Tumoral/genéticaRESUMO
With the emergence of challenges in the environmental degradation and resource scarcity fields, the research of biobased self-healing polyurethane (BSPU) has become a prevailing trend in the technology of the polyurethane industry and a promising direction for developing biomass resources. Here, the production of BSPU from lignocellulose, vegetable oil, chitosan, collagen, and coumarin is classified, and the principles of designing polyurethane based on compelling examples using the latest methods and current research are summarized. Moreover, the impact of biomass materials on self-healing and mechanical properties, as well as the tailored performance method, are presented in detail. Finally, the applications of BSPU in biomedicine, sensors, coatings, etc. are also summarized, and the possible challenges and development prospects are explored to helpfully make progress in the development of BSPU. These findings demonstrate valuable references and practical significance for future BSPU research.
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Quitosana , Poliuretanos , BiomassaRESUMO
INTRODUCTION: Cement distribution pattern following unipedicle percutaneous vertebroplasty (UVP) for osteoporotic vertebral compression fractures (OVCFs) has been reported in association with clinical results. The present retrospective study aimed to classify the bone cement distribution types following UVP and investigate the differences in clinical efficacy and related complications. MATERIALS AND METHODS: We retrospectively reviewed the medical records of the patients with single-segment OVCFs who underwent UVP. Cement distribution patterns were divided into the diffuse, block, double band, and single band types according to the plain radiographs and further by cement filling rate (CFR) based on a three-dimension reconstruction of post-operative CT. The cutoff values of CFR were > 34% for the diffuse, block between 34 and 20%, and each band of the double or single band < 20%. Clinical efficacy and related complications were compared among the four cement distribution types 24 h after the operation and the last follow-up. RESULTS: A total of 155 patients with an average follow-up time of 20.3 months were included. The diffuse type included 26 patients; block, 87; double band, 18; and single band, 24. The VAS and ODI after operation improved significantly in all four groups. The diffuse and block types had similar clinical results. The clinical outcomes in the single band group were the poorest at the last follow-up. The patients with single band type also had the highest rates of body re-collapse and revision surgery for the index level. CONCLUSION: Diffuse and block groups can better maintain the height of the vertebral body and reduce the risk of vertebral body recompression. The single band has the poorest results, and intraoperative immediate contralateral vertebroplasty was highly recommended.
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Fraturas por Compressão , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Estudos Retrospectivos , Cimentos Ósseos/uso terapêutico , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/cirurgia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Vertebroplastia/métodos , Resultado do TratamentoRESUMO
Shipborne atomic gravimeter (SAG) is an instrument that can directly measure absolute gravity in dynamic environments. As a new type of gravity sensor, a standard method for evaluating its detailed performance has not been proposed and the detailed performance of SAG was rarely reported. In this paper, a system of dynamic gravity measurement, which was integrated with a home-made atomic gravimeter, is demonstrated, and a novel and simple method for testing the performance of SAG on the lake based on the modulated Coriolis effect is put forward. Firstly, in the state of ship mooring, a tilt modulation of the gravity sensor has been realized to make sure the Raman wave vector is parallel to the gravity axis. Moreover, a comparison between the measurement result of CG-5 and SAG has also been carried out to evaluate the accuracy of the SAG. Then, the Coriolis effect modulating experiment is carried out with various routes on lake to test its performance in dynamic environments. In the ship mooring state, the accuracy has been demonstrated to be 0.643 mGal. The internal consistency reliabilities are evaluated to be 0.8 mGal and 1.2 mGal under the conditions of straight line and circle navigation, respectively.
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Força Coriolis , Gravitação , NaviosRESUMO
In an atomic fountain, atoms in motion can be spatially separated into discrete Zeeman sub-states by magnetically induced Stern-Gerlach effect. With resonant light pulses acting as a shutter, specific states are selected for subsequent experiments. Such separation-selection process in atomic optics is the analogue of a spatial filter in physical optics which selects and purifies the modes of light. This technique is demonstrated by injecting a pulsed current in a circular coil around a vertical atomic fountain, separating the pre-cooled Rubidium atoms by a distance of centimeters in between, and filtering each single sub-state with block pulses. The filtered atoms after the process is highly purified in the desired sub-state. The apparatus of the atomic spatial filter is adaptable in atomic optics and can be integrated into the high-vacuum chamber of an atomic fountain.
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Electrochemical measurements at the single entity level provide ultra-sensitive tools for the precise diagnosis and understanding of basic biological and chemical processes. By decoding current signatures, single-entity electrochemistry provides abundant information on charges, sizes, shapes, catalytic performances and compositions. The accuracy of single-entity electrochemistry highly relies on advanced instrumentation to achieve the amperometric resolution at the sub-picoampere level and the temporal resolution at the sub-microsecond level. Currently, it is still a challenge for paralleling amplifiers to allow low-noise and high bandwidth single-entity electrochemical measurements. Herein, we developed a low-noise four-channel electrochemical instrumentation that integrates an Au electrode array with amplifiers in the circuit board. With this amplifier array, we achieved a high bandwidth (>100 kHz) electrochemical measurement. The further practical experiments proved the capability of this amplifier array system in acquiring transient signals from both single-molecule detection with an aerolysin nanopore and single Pt nanoparticle catalysis during the dynamic collision process. Paired with appropriate microfluidic array systems, our instrumentation will enable an extraordinarily high-throughput feature for single-entity sensing.
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Nanoporos , Catálise , Eletroquímica , Eletrodos , NanotecnologiaRESUMO
NASA's New Horizons mission unveiled a diverse landscape of Pluto's surface with massive regions being neutral in color, while others like Cthulhu Macula range from golden-yellow to reddish comprising up to half of Pluto's carbon budget. Here, we demonstrate in laboratory experiments merged with electronic structure calculations that the photolysis of solid acetylene - the most abundant precipitate on Pluto's surface - by low energy ultraviolet photons efficiently synthesizes benzene and polycyclic aromatic hydrocarbons via excited state photochemistry thus providing critical molecular building blocks for the colored surface material. Since low energy photons deliver doses to Pluto's surface exceeding those from cosmic rays by six orders of magnitude, these processes may significantly contribute to the coloration of Pluto's surface and of hydrocarbon-covered surfaces of Solar System bodies such as Triton in general. This discovery critically enhances our perception of the distribution of aromatic molecules and carbon throughout our Solar System.
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Photochemistry of an N2 ice and thermal reaction of the irradiated sample were studied with vacuum-ultraviolet (VUV) light from a synchrotron. Concurrent detection of infrared absorption and visible emission spectra provide evidence for the generation of energetic products N (2D) and N (2P) atoms, N2 (A) molecule and linear-N3 (l-N3) radical after excitation of icy N2 at 121.6 nm. Irradiation at 190 nm is shown to be an effective way to eliminate the l-N3 radical. After the photolysis and photoelimination of the l-N3, we initiate synthesis of l-N3 via the thermal ramping of the sample in temperature range 3.5 to 20 K. In addition, the emission from the N (2D) atom was observed during the thermal ramping process. These behaviors indicate that a long-lived N (2Dlong) atom is generated in the VUV-photolyzed N2 ice. A comparison of the variations of the visible emission of N (2D) and the infrared absorption of l-N3 with time indicates that the long-lived N (2Dlong) dominated the thermal synthesis of l-N3 The results have enhanced suggestion and understanding of the conversion for nitrogen species in cold astrophysical environments with VUV irradiation.