The ionization dynamics of two-electron atom in an intense laser field is studied by the Bohmian mechanics(BM)theory, and the xenon atomic potential function is used as a model. The single ionization process and doubl...The ionization dynamics of two-electron atom in an intense laser field is studied by the Bohmian mechanics(BM)theory, and the xenon atomic potential function is used as a model. The single ionization process and double ionization process are calculated by the BM theory and their results are in good agreement with those calculated by numerically solving the time-dependent Schrodinger equation. The analyses of the types, trajectories, and forces of Bohmian particles(BPs)undergoing the single and double ionizations indicate that the re-collision process accounts for a considerable proportion in the singly ionized cases. Furthermore, the analysis of the work done by the external force acting on the BPs shows that the quantum force plays an important role in the re-collision process. This work is helpful in understanding the ionization of two-electron atom in an intense laser field.展开更多
Resonance enhanced two-photon ionization process of hydrogen atom via the resonant laser pulse is studied by Bohmian mechanics (BM) method. By analyzing the trajectories and energies of Bohmian particles (BPs), we fin...Resonance enhanced two-photon ionization process of hydrogen atom via the resonant laser pulse is studied by Bohmian mechanics (BM) method. By analyzing the trajectories and energies of Bohmian particles (BPs), we find that under the action of high frequency and low intensity multi-circle resonant laser pulses, the ionized BPs first absorb one photon completing the excitation, and then absorb another photon, completing the ionization after staying in the first excited state for a period of time. The analysis of work done by the forces shows that the electric field force and quantum force play a major role in the whole ionization process. At the excitation moment and in the excitation-ionization process, the effect of the quantum force is greater than that of the electric field force. Finally, we discuss the principle of work and energy for BPs, and find that the electric field force and quantum force are non-conservative forces whose work is equal to the increment of mechanical energy of the system. In addition, it is proved that the quantum potential energy actually comes from the kinetic energy of the system and the increment of kinetic energy is equal to that of the kinetic energy of the system.展开更多
为了消除原子力显微镜(atomic force microscopy,AFM)在测量光栅常数时探针和噪声造成的光栅常数评定误差,利用MATLAB对不同形状参数的探针扫描图像进行仿真。分析了探针结构对扫描结果的影响,提出基于形态学探针重建算法评定光栅常数,...为了消除原子力显微镜(atomic force microscopy,AFM)在测量光栅常数时探针和噪声造成的光栅常数评定误差,利用MATLAB对不同形状参数的探针扫描图像进行仿真。分析了探针结构对扫描结果的影响,提出基于形态学探针重建算法评定光栅常数,通过标定方式和改进Garcia探针模型进行形态学探针重建来消除探针和噪声误差。实验结果表明:该算法提高了实际AFM测量光栅常数的精确度。展开更多
This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC...This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC, FTIR, and ~1H-NMR. The buffering capacity of polyethylene glycol-distearoyl phosphatidylethanolamine(PEG-DSPE) and TPOS was determined by acid-base titration, and TPOS displayed a slower downtrend and gentler slope of titration curve than PEG-DSPE within pH 7.4–5.0. Studies on the in vitro drug release demonstrated that TPOS modified docetaxel(DOC) liposomes(TPOS-DOC-L) had a slower drugrelease rate at pH 7.4 similar to PEGylated-DOC liposomes(PEG-DOC-L), whereas the release rate reached approximately 86.92% ± 1.69% at pH 6.4. In vitro cellular uptake assays by microplate reader, and flow cytometry revealed that TPOS modified coumarin 6 liposomes(TPOS-C6-L) had stronger cellular uptake at pH 6.4 than that at pH 7.4( P < 0.01). Conversely, for PEGylated C6 liposomes(PEG-C6-L) and conventional C6 liposomes(C6-L), very similar cellular uptakes were exhibited at different pH values. Confocal laser scanning microscopy images showed that PEG-C6-L and C6-L were mainly located in lysosomes. By contrast, TPOS-C6-L showed broader cytoplasmic release and distribution at 4 h. MTT assay showed that the cytotoxicity of TPOS-DOC-L was similar to that of PEG-DOC-L and conventional DOC liposomes(DOC-L) at the same DOC concentration and at pH 7.4, but was much lower than those at pH 6.4 after 48 h of incubation. The apoptosis of PEG-DOC-L and DOC-L had no remarkable improvement with decreased pH from 7.4 to 6.4. Meanwhile, TPOS-DOC-Lsignificantly induced the apoptosis of HeLa cells with decreased pH. Therefore, TPOS can be a biomaterial for the construction of a pH-sensitive drug delivery system.展开更多
Acupuncture has been used for centuries to heal the body;it is essential to comprehend the mechanism of acupuncture within the modern medical framework.By far much research provided a modern scientific understanding o...Acupuncture has been used for centuries to heal the body;it is essential to comprehend the mechanism of acupuncture within the modern medical framework.By far much research provided a modern scientific understanding of how acupuncture works,most of them indicated that nervous system is involved.However,few studies have been conducted on how acupuncture trigger the nervous system.When the thin needle inserts the acupoint,the mechanical stress generated by acupuncture is the key factor of acupuncture effect.The first peripheral receptors activated in this process are mechanoreceptors,which are sensitive to mechanical forces.The purpose of this review is to explore the connection between the mechanoreceptors located in the skin and subcutaneous tissues and the acupuncture therapy.It also attempts to clue the possible roles of mechanoreceptors in the skin surface and subcutaneous tissue during the acupuncture manipulation and electroacupuncture.展开更多
Pain on the body surface can accompany disorders in the deep tissue or internal organs. However, the anatomical and physiological mechanisms are obscure.Here, we provided direct evidence of axon bifurcation in primary...Pain on the body surface can accompany disorders in the deep tissue or internal organs. However, the anatomical and physiological mechanisms are obscure.Here, we provided direct evidence of axon bifurcation in primary C-nociceptive neurons that innervate both the skin and a visceral organ. Double-labeled dorsal root ganglion(DRG) neurons and Evans blue extravasation were observed in 3 types of chemically-induced visceral inflammation(colitis, urocystitis, and acute gastritis) rat models.In the colitis model, mechanical hypersensitivity and spontaneous activity were recorded in vivo from doublelabeled C-nociceptive neurons in S1 or L6 DRGs. These neurons showed significantly enhanced responses to both somatic stimulation and colorectal distension. Our findings suggest that the branching of C-nociceptor axons contribute to cutaneous hypersensitivity in visceral inflammation. Cutaneous hypersensitivity on certain locations of the body surface might serve as an indicator of pathological conditions in the corresponding visceral organ.展开更多
基金Project supported by the Jilin Provincial Science and Technology Development Plan Program for Excellent Youth Talents,China(Grant No.20180520174JH)the National Natural Science Foundation of China(Grant Nos.11704145,11904050,11774129,11747007,11534004,and 12074145).
文摘The ionization dynamics of two-electron atom in an intense laser field is studied by the Bohmian mechanics(BM)theory, and the xenon atomic potential function is used as a model. The single ionization process and double ionization process are calculated by the BM theory and their results are in good agreement with those calculated by numerically solving the time-dependent Schrodinger equation. The analyses of the types, trajectories, and forces of Bohmian particles(BPs)undergoing the single and double ionizations indicate that the re-collision process accounts for a considerable proportion in the singly ionized cases. Furthermore, the analysis of the work done by the external force acting on the BPs shows that the quantum force plays an important role in the re-collision process. This work is helpful in understanding the ionization of two-electron atom in an intense laser field.
基金Project supported by Jilin Province Science and Technology Development Plan Project-Excellent Youth Talents Fund Project,China(Grant No.20180520174JH)the National Natural Science Foundation of China(Grant Nos.1170414511904050,11774129,11747007,and 11534004).
文摘Resonance enhanced two-photon ionization process of hydrogen atom via the resonant laser pulse is studied by Bohmian mechanics (BM) method. By analyzing the trajectories and energies of Bohmian particles (BPs), we find that under the action of high frequency and low intensity multi-circle resonant laser pulses, the ionized BPs first absorb one photon completing the excitation, and then absorb another photon, completing the ionization after staying in the first excited state for a period of time. The analysis of work done by the forces shows that the electric field force and quantum force play a major role in the whole ionization process. At the excitation moment and in the excitation-ionization process, the effect of the quantum force is greater than that of the electric field force. Finally, we discuss the principle of work and energy for BPs, and find that the electric field force and quantum force are non-conservative forces whose work is equal to the increment of mechanical energy of the system. In addition, it is proved that the quantum potential energy actually comes from the kinetic energy of the system and the increment of kinetic energy is equal to that of the kinetic energy of the system.
文摘为了消除原子力显微镜(atomic force microscopy,AFM)在测量光栅常数时探针和噪声造成的光栅常数评定误差,利用MATLAB对不同形状参数的探针扫描图像进行仿真。分析了探针结构对扫描结果的影响,提出基于形态学探针重建算法评定光栅常数,通过标定方式和改进Garcia探针模型进行形态学探针重建来消除探针和噪声误差。实验结果表明:该算法提高了实际AFM测量光栅常数的精确度。
基金supported by National Natural Science Foundation of China (81102394)Natural Science Foundation of Liaoning Province (20170540575)
文摘This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC, FTIR, and ~1H-NMR. The buffering capacity of polyethylene glycol-distearoyl phosphatidylethanolamine(PEG-DSPE) and TPOS was determined by acid-base titration, and TPOS displayed a slower downtrend and gentler slope of titration curve than PEG-DSPE within pH 7.4–5.0. Studies on the in vitro drug release demonstrated that TPOS modified docetaxel(DOC) liposomes(TPOS-DOC-L) had a slower drugrelease rate at pH 7.4 similar to PEGylated-DOC liposomes(PEG-DOC-L), whereas the release rate reached approximately 86.92% ± 1.69% at pH 6.4. In vitro cellular uptake assays by microplate reader, and flow cytometry revealed that TPOS modified coumarin 6 liposomes(TPOS-C6-L) had stronger cellular uptake at pH 6.4 than that at pH 7.4( P < 0.01). Conversely, for PEGylated C6 liposomes(PEG-C6-L) and conventional C6 liposomes(C6-L), very similar cellular uptakes were exhibited at different pH values. Confocal laser scanning microscopy images showed that PEG-C6-L and C6-L were mainly located in lysosomes. By contrast, TPOS-C6-L showed broader cytoplasmic release and distribution at 4 h. MTT assay showed that the cytotoxicity of TPOS-DOC-L was similar to that of PEG-DOC-L and conventional DOC liposomes(DOC-L) at the same DOC concentration and at pH 7.4, but was much lower than those at pH 6.4 after 48 h of incubation. The apoptosis of PEG-DOC-L and DOC-L had no remarkable improvement with decreased pH from 7.4 to 6.4. Meanwhile, TPOS-DOC-Lsignificantly induced the apoptosis of HeLa cells with decreased pH. Therefore, TPOS can be a biomaterial for the construction of a pH-sensitive drug delivery system.
基金National Natural Science Foundation of China(NSFC)81973967.
文摘Acupuncture has been used for centuries to heal the body;it is essential to comprehend the mechanism of acupuncture within the modern medical framework.By far much research provided a modern scientific understanding of how acupuncture works,most of them indicated that nervous system is involved.However,few studies have been conducted on how acupuncture trigger the nervous system.When the thin needle inserts the acupoint,the mechanical stress generated by acupuncture is the key factor of acupuncture effect.The first peripheral receptors activated in this process are mechanoreceptors,which are sensitive to mechanical forces.The purpose of this review is to explore the connection between the mechanoreceptors located in the skin and subcutaneous tissues and the acupuncture therapy.It also attempts to clue the possible roles of mechanoreceptors in the skin surface and subcutaneous tissue during the acupuncture manipulation and electroacupuncture.
基金supported by Grants from the National Science Foundation of China(81771205,91632113,81973963,81674085,and 81674075)the National Key Research and Development Program of China(2018YFC1704600)+1 种基金the Natural Science Foundation and Major Basic Research Program of Shanghai(16JC1420500 and 16JC1420502)the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2017-I2M-3-008)。
文摘Pain on the body surface can accompany disorders in the deep tissue or internal organs. However, the anatomical and physiological mechanisms are obscure.Here, we provided direct evidence of axon bifurcation in primary C-nociceptive neurons that innervate both the skin and a visceral organ. Double-labeled dorsal root ganglion(DRG) neurons and Evans blue extravasation were observed in 3 types of chemically-induced visceral inflammation(colitis, urocystitis, and acute gastritis) rat models.In the colitis model, mechanical hypersensitivity and spontaneous activity were recorded in vivo from doublelabeled C-nociceptive neurons in S1 or L6 DRGs. These neurons showed significantly enhanced responses to both somatic stimulation and colorectal distension. Our findings suggest that the branching of C-nociceptor axons contribute to cutaneous hypersensitivity in visceral inflammation. Cutaneous hypersensitivity on certain locations of the body surface might serve as an indicator of pathological conditions in the corresponding visceral organ.
