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1.
Phys Chem Chem Phys ; 26(25): 17599-17608, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38864183

ABSTRACT

We conducted a study on the trajectory-dependent threshold effects of proton stopping power in LiF nanosheets using time-dependent density functional theory non-adiabatically coupled to the molecular dynamics. This study covered protons with initial velocities in the range of 0.1-1.0 a.u., offering a vast amount of detailed information on the electronic structure during the stopping process with superior spatial and temporal resolution. Our results show that the impact parameters of incident protons play a crucial role in determining the threshold behavior of proton stopping power in LiF nanosheets. Most importantly, we found that close collisions do not exhibit a discernible threshold. In addition, the research results also revealed the time dependence of the number of electrons occupying the atomic orbitals of F and Li as protons pass through the nanosheets.

2.
Phys Chem Chem Phys ; 25(28): 18932-18941, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37408492

ABSTRACT

The stopping power of energetic He ions traversing an Al film is studied by combining the time-dependent density-functional theory method with molecular dynamics simulations. We investigated the dependence of the semicore electron excitation of the Al film on the projectile's trajectory and its charge state. Our results show that for the off-channeling trajectories the semicore electrons contribute significantly to the stopping power of the Al film as the He+ ion velocity exceeds 1.0 a.u, and in contrast, it is negligible for the channeling trajectories. Most importantly, we found two unexpected effects of semicore electrons on the stopping power in helium-irradiated aluminum nanosheets, i.e., (1) the semicore electrons can contribute to the energy loss for both high and low energy projectiles under the off-channeling trajectory; (2) as the projectile velocity increases from 0.4 a.u. to 2.0 a.u. although semicore electron excitation (including transition in the target, ionization away from the target and transfer to the projectile ion) of the target atom is gradually inhibited, the influence of semicore electrons on valence electron excitation is gradually enhanced. Our finding allows us to gain new insights into the stopping of ions in metals.

3.
Zhongguo Zhong Yao Za Zhi ; 45(22): 5537-5554, 2020 Nov.
Article in Zh | MEDLINE | ID: mdl-33350217

ABSTRACT

In this study, the chemical profiling of Jingyin Granules and the tissue distribution of nine major constituents in this Chinese medicine were performed after oral administration of Jingyin Granules to rats, by using UHPLC-Q-Exactive Orbitrap HR-MS. An Acquity UPLC BEH C_(18) chromatographic column(2.1 mm×100 mm, 1.7 µm) was used as solid phase, while the mobile phase was methanol and 0.1% formic acid water for gradient elution. The major constituents in this Chinese medicine were quickly and accurately identified, via comparison with the retention times and MS/MS spectra of the standards. A total of 106 chemicals were identified from Jingyin Granules, including 24 kinds of organic acids, 47 kinds of flavonoids, 10 kinds of iridoids, and 21 kinds of saponins and 4 kinds of other compounds. After oral administered Jingyin Granules to rats, 48, 30, 25, 23, 45, 34, 39, 26, 19 prototype compounds were identified in serum, heart, liver, spleen, lung, kidney, brain, fat, and testicles, respectively. Meanwhile, an LC-MS based analytical method was established for simultaneous determination of chlorogenic acid, swertiamarin, caffeic acid, sweroside, liquiritin, prim-O-glucosylcimifugin, arctiin, 5-O-methylvisammioside and arctigenin in biological samples. The tissue distribution(serum, liver and lung) of these nine aim constituents in rats after oral administration of Jingyin Granules were investigated. It was found that these nine constituents could be quickly absorbed into circulation system and then distributed to liver and lung tissues. Except arctigenin, the exposure of other eight aim constituents to serum and lung was peaked at 1 h. At 1 h, the exposure of these components to lung tissue were ranked as follows: swertiamarin [(75 191.0±3 483.21) ng·g~(-1)]>arctiin [(2 716.5±36.06) ng·g~(-1)]>5-O-methylvisammioside [(585.1±0.71) ng·g~(-1)]>arctigenin [(437.45±3.18) ng·g~(-1)]>chlorogenic acid [(308.1±5.66) ng·g~(-1)]>prim-O-glucosylcimifugin [(211.35±2.19) ng·g~(-1)]>sweroside [(184.3±9.05) ng·g~(-1)]>caffeic acid [(175.95±2.05) ng·g~(-1)]>liquiritin [(174.78±153.34) ng·g~(-1)]. In summary, an UHPLC-Q-Exactive Orbitrap HR-MS method has been established for rapid and accurate identification of the constituents in Jingyin Granules, while the tissue distribution of nine major absorpted constituents were investigated in rats following oral administration of Jingyin Granules. These findings provided key information and guidance for further studies on pharmacodynamic substances and clinical applications of Jingyin Granules.


Subject(s)
Drugs, Chinese Herbal , Tandem Mass Spectrometry , Animals , Chromatography, High Pressure Liquid , Chromatography, Liquid , Rats , Tissue Distribution
4.
J Chem Phys ; 140(12): 124306, 2014 Mar 28.
Article in English | MEDLINE | ID: mdl-24697440

ABSTRACT

Using time-dependent density functional theory, applied to the valence electrons and coupled non-adiabatically to molecular dynamics of the ions, we study the ionization and fragmentation of formaldehyde in collision with a proton. Four different impact energies: 35 eV, 85 eV, 135 eV, and 300 eV are chosen in order to study the energy effect in the low energy region, and ten different incident orientations at 85 eV are considered for investigating the steric effect. Fragmentation ratios, single, double, and total electron ionization cross sections are calculated. For large impact parameters, these results are close to zero irrespective of the incident orientations due to a weak projectile-target interaction. For small impact parameters, the results strongly depend on the collision energy and orientation. We also give the kinetic energy releases and scattering angles of protons, as well as the cross section of different ion fragments and the corresponding reaction channels.

5.
J Chem Phys ; 140(5): 054308, 2014 Feb 07.
Article in English | MEDLINE | ID: mdl-24511941

ABSTRACT

In this work we make an investigation on collision dynamics of H(+) + CH4 at 30 eV by using time-dependent density functional theory coupled with molecular dynamics approach. All possible reactions are presented based on 9 incident orientations. The calculated fragment intensity is in nice agreement with experimental results. The mechanism of reaction transition for dissociation and proton exchange processes is explained by the intra-molecule energy transfer. However, the energy loss of the proton is in poor agreement with experimental results. The discrepancy is attributed to the mean-field treatment of potential surface. We also studied the dependence on initial velocity of both proton and methane. In addition, we find that for dynamical evolution a different self-interaction correction (SIC) may lead to different results, but with respect to the position of rainbow angle, average-density SIC seems to have reasonable correction.


Subject(s)
Hydrogen/chemistry , Methane/chemistry , Molecular Dynamics Simulation , Quantum Theory
6.
Phys Rev E ; 110(2-2): 025202, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39295003

ABSTRACT

Modeling the nonequilibrium process between ions and electrons is of great importance in laboratory fusion ignition, laser-plasma interaction, and astrophysics. For hot and dense plasmas, theoretical descriptions of Coulomb collisions remain complicated due to quantum effect at short distances and screening effect at long distances. In this paper, we propose an analytical screened quantum statistical potential that takes into account both the short-range quantum diffraction effect and the long-range screening effect. By implementing the newly developed potential into the binary scattering framework, the electron-proton temperature relaxation in hot-dense hydrogen plasmas is investigated. In both the classical and quantum limits, analytical expressions for the Coulomb logarithm have been obtained, which are generally embedded in an asymptotic matching formula. Quantitative comparisons with molecular dynamics simulations and recent OMEGA experiments demonstrate that the present modeling is well suited to describe the temperature relaxation process between electrons and ions in hot-dense plasmas.

7.
Phys Rev E ; 107(1-2): 015203, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36797881

ABSTRACT

Electron-proton energy relaxation rates are assessed using molecular dynamics (MD) simulations in weakly-coupled hydrogen plasmas. To this end, we use various approaches to extract the energy relaxation rate from MD-simulated temperatures, and we find that existing extracting approaches may yield results with a sizable discrepancy larger than the variance between analytical models, which is further verified by well-known case studies. Present results show that two of the extracting approaches can produce identical results, which is attributed to a proper treatment of relaxation evolution. To discriminate the use of various methods, an empirical criterion with respect to initial plasma temperatures is proposed, which can self-consistently explain the cases considered. In addition, for a transient electron-proton plasma, we show that it is possible to extrapolate the Coulomb logarithm from that derived by initial plasma parameters in a single MD calculation, which is reasonably consistent with previous MD data. Our results are helpful to obtain accurate MD-based energy relaxation rates.

8.
Phys Rev E ; 105(1-1): 014131, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35193297

ABSTRACT

We study the mechanism of the impact of random media on the stochastic radiation transport based on a one-dimensional (1D) planar model. To this end, we use a random sampling of mixtures combined with a deterministic solution of the time-dependent radiation transport equation coupled to a material temperature equation. Compared to purely absorbing cases [C.-Z. Gao et al., Phys. Rev. E 102, 022111 (2020)10.1103/PhysRevE.102.022111], we find that material temperatures can significantly suppress the impact of mixing distribution and size, which is understood from the analysis of energy transport channels. By developing a steady-state stochastic transport model, it is found that the mechanism of transmission of radiation is distance dependent, which is closely related to the mean free path of photons l_{p}. Furthermore, we suggest that it is the relationship between l_{p} and L (the width of random medium) that determines the impact of random media on the stochastic radiation transport, which is further corroborated by additional simulations. Most importantly, combining the proposed simple relationship and 1D simulations, we resolve the existing disputable issue of the impact of random media in previous multidimensional works, showing that multidimensional results are essentially consistent and the observed weak or remarkable impact of random media is mainly due to the distinctly different relationship between l_{p} and L. Our results may have practical implications in relevant experiments of stochastic radiative transfer.

9.
Front Oncol ; 12: 876967, 2022.
Article in English | MEDLINE | ID: mdl-35860551

ABSTRACT

Background: An increasing proportion of patients with diabetic kidney disease (DKD) has been observed among incident hemodialysis patients in large cities, which is consistent with the continuous growth of diabetes in the past 20 years. Purpose: In this multicenter retrospective study, we developed a deep learning (DL)-based automatic segmentation and radiomics technology to stratify patients with DKD and evaluate the possibility of clinical application across centers. Materials and Methods: The research participants were enrolled retrospectively and separated into three parts: training, validation, and independent test datasets for further analysis. DeepLabV3+ network, PyRadiomics package, and least absolute shrinkage and selection operator were used for segmentation, extraction of radiomics variables, and regression, respectively. Results: A total of 499 patients from three centers were enrolled in this study including 246 patients with type II diabetes mellitus (T2DM) and 253 patients with DKD. The mean intersection-over-union (Miou) and mean pixel accuracy (mPA) of automatic segmentation of the data from the three medical centers were 0.812 ± 0.003, 0.781 ± 0.009, 0.805 ± 0.020 and 0.890 ± 0.004, 0.870 ± 0.002, 0.893 ± 0.007, respectively. The variables from the renal parenchyma and sinus provided different information for the diagnosis and follow-up of DKD. The area under the curve (AUC) of the radiomics model for differentiating between DKD and T2DM patients was 0.674 ± 0.074 and for differentiating between the high and low stages of DKD was 0.803 ± 0.037. Conclusion: In this study, we developed a DL-based automatic segmentation, radiomics technology to stratify patients with DKD. The DL technology was proposed to achieve fast and accurate anatomical-level segmentation in the kidney, and an ultrasound-based radiomics model can achieve high diagnostic performance in the diagnosis and follow-up of patients with DKD.

10.
Zhonghua Yi Xue Za Zhi ; 91(28): 1977-81, 2011 Jul 26.
Article in Zh | MEDLINE | ID: mdl-22093894

ABSTRACT

OBJECTIVE: To evaluate the safety of enterovirus type 71 (EV71) inactivated vaccine (human diploid derived) for infection prevention in an animal model by investigating the immune responses and related patho-inflammatory reactions. METHODS: In the neonatal monkey model for EV71 vaccine protection, vaccinated group (n = 4) and unvaccinated group (n = 4) were attacked with live virus at the same time, the parameters of clinical observations, antibodies and inflammatory factors in peripheral blood and cerebrospinal fluid (CSF) were detected. And the pathological changes in major organs were used to determine the patho-inflammatory reactions during the immune responses elicited by vaccination. RESULTS: The neutralizing antibodies of vaccine group reach to 1:32. There was no obvious changes of inflammatory factors in peripheral blood and CSF of monkeys challenged or unchallenged by live virus. In peripheral blood of unvaccinated group, the level of basophilic granulocyte higher 4 - 5 times than normal level and the interferon-γ (IFN-γ) showed obvious increase. Live virus infected after 7 days, the interleukin-6 (IL-6) and IFN-γ in peripheral blood of unvaccinated group (18.5, 12.7 pg/ml) were higher than vaccinated group (10.2, 7.6 pg/ml). Furthermore, the IL-6 in CSF (102.0 pg/ml) had 4 - 5 times increased than vaccinated group (12.4 pg/ml) at 7 days after virus exposure. Meanwhile, the pathological analysis revealed that no obvious changes were detected in CNS and other organs of vaccinated monkeys challenged with live virus. However, the pathological damages induced by virus infection could be determined in the unvaccinated control monkeys, including neuronal damage, massive cellular infiltration associated with pulmonary edema/hemorrhage and pulmonary/bronchial damage due to an infiltration of inflammatory cells. CONCLUSION: Capable of inducing an immune response, the EV71 inactivated vaccine offers protection to neonatal rhesus monkeys against the attacks of live virus. Based on the results of no patho-inflammatory reaction and pathological damage after viral infection in vaccinated animals, the excellent safety of this vaccine may be confirmed in neonatal monkey.


Subject(s)
Enterovirus A, Human/immunology , Enterovirus Infections/prevention & control , Inflammation/immunology , Viral Vaccines/immunology , Animals , Antibodies, Viral/blood , Enterovirus Infections/immunology , Immunity , Interferon-gamma/metabolism , Interleukin-6/cerebrospinal fluid , Macaca mulatta , Vaccination , Vaccines, Inactivated/immunology
11.
RSC Adv ; 10(60): 36287-36294, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-35517921

ABSTRACT

Nitrogen-rich energetic materials (EMs) have been widely studied because of their high thermal stability, insensitivity, excellent detonation performance and non-toxic characteristics. In particular, these compounds are well applied as gas-generating agents (GGAs). As a nitrogen-rich heterocyclic framework, 1,2,4,5-tetrazine derivatives have shown great potential in the design of GGAs. The guanidine salts of 3,6-bis-nitroguanyl-1,2,4,5-tetrazine (DNGTz), guanidine (G2DNGTz) (1), aminoguanidine (AG2DNGTz) (2), diaminoguanidine (DAG2DNGTz) (3), and triaminoguanidine (TAG2DNGTz) (4) have been synthesized and characterized by elemental analysis and FT-IR. The crystal structures of 1 and 2 were obtained by X-ray single crystal diffraction. Crystal analysis shows that 1 and 2 arrange through zigzag-chain-like assembly and face-to-face geometries, which is helpful in decreasing mechanical sensitivity. The thermal stability and thermal decomposition kinetics of these four salts were studied by Differential Scanning Calorimetry (DSC). Furthermore, the thermogravimetry-Fourier transform infrared-mass spectrometry (TG-FTIR-MS) analysis of thermal decomposition products reveals that the main decomposition gaseous products are H2O, N2O, CO2, NO, N2 and NH3. Then, the cytotoxicity of the four salts was tested by MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) method, and it was found that salts 1-4 show slight cytotoxicity in mouse fibroblasts (L929), at a concentration of 0.125 mg ml-1. The insensitivity, low toxicity, and production of clean gases without solid residue after burning of salt 1 indicate that it can be used as a potential green energetic material for GGAs.

12.
Phys Rev E ; 102(2-1): 022111, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32942389

ABSTRACT

We study stochastic radiation transport through random media in one dimension, in particular for pure absorbing cases. The statistical model to calculate the ensemble-averaged transmission for a binary random mixture is derived based on the cumulative probability density function (PDF) of optical depth, which is numerically simulated for both Markovian and non-Markovian mixtures by Monte Carlo calculations. We present systematic results about the influence of mixtures' stochasticity on the radiation transport. It is found that mixing statistics affects the ensemble-averaged intensities mainly due to the distribution of cumulative PDF at small optical depths, which explains well why the ensemble-averaged transmission is observed to be sensitive to chord length distribution and its variances. The effect of the particle size is substantial when the mixtures' correlation length is comparable to the mean free path of photons, which imprints a moderately broad transition region into the cumulative PDF. With the mixing probability increasing, the intensity decreases nearly exponentially, from which the mixing zone length can be approximately estimated. The impact of mixed configuration is also discussed, which is in line with previous results.

13.
Article in Zh | WPRIM | ID: wpr-1019013

ABSTRACT

Objective To understand the intention of the community diabetes management application and analyze the related factors.Methods Diabetes patients in the community were selected as the research objects,and the diabetes management application intention scale,diabetes electronic health literacy scale,diabetes self-management ability scale and general information questionnaire were randomly conducted for the investigation.Results The score of 286 cases of community diabetes management application intention was 44.38±8.56,the qualification rate was 67.4%,the score of diabetes e-health literacy score was 22.38±7.56,the qualification rate was 28.2%,and the score of diabetes self-management ability score was 43.41±7.96.Through the analysis,it was found that diabetes management application intention,e-health literacy,and self-management ability were affected by patients'education,age,and income.The analysis of related factors showed that the intention to use the diabetes management application was positively related to the electronic health literacy and self-management ability of patients P<0.05.Conclusion The intention to use community diabetes management application is affected by income,education level,age,e-health literacy and self-management ability.The overall level of e-health literacy and self-management ability of diabetes patients is low.It is necessary to improve the e-health literacy and self-management level of diabetes patients.

14.
Article in Zh | WPRIM | ID: wpr-1016759

ABSTRACT

Background Pulmonary fibrosis currently lacks screening and diagnostic methods in the early stages and effective treatments in the later stages, so there is an urgent need to explore the mechanisms and develop targeted treatments. Objective To screen the expression of differentially expressed circular RNA (circRNA) hsa_circUCK2 under pathological conditions and to explore its effect on pulmonary fibrosis. Methods In the cell-based experiments, hsa_circUCK2 was knocked down in HPF-a cells using small interfering RNA (siRNA), and HPF-a cells were stimulated by TGF-β1. Four groups were set up: si-NC group, si-circUCK2 group, si-NC+TGF-β1-treated group, and si-circUCK2+TGF-β1-treated group. Western blot assay was used to detect the expression of fibronectin (FN1) in HPF-a cells of the four groups, scratch assay was used to detect the migration ability of HPF-a cells, and CCK-8 assay was used to detect the proliferation ability of HPF-a cells in the two groups with TGF-β1 stimulation, the si-NC+TGF-β1-treated group and the si-circUCK2+TGF-β1-treated group. In the animal experiments, forty-eighty healthy SPF-grade male C57BL/6 mice were randomly divided into four groups: saline+si-con group, saline+si-circ_0000115 group, SiO2+si-con group, and SiO2+si-circ_0000115 group. Mouse lung circRNA mmu_circ_0000115 (mouse homolog of hsa_circUCK2) was knocked down by tracheal drip injection of siRNA, and a mouse lung fibrosis model was constructed by tracheal drip injection of SiO2 suspension (0.2 g·kg−1, 50 mg·mL−1) after 48 h. Real-time fluorescence quantitative PCR was used to detect the knockout efficiency in each organ of the mouse, Western blot was applied to detect the expression of type I collagen α2 (COL1A2) in the lung tissues, and Sirius red was used to detect collagen synthesis in the lung tissues. Results In the cell-based experiments, after the knockdown of hsa_circUCK2, the Western blot results showed that the expression level of the FN1 protein in TGF-β1-stimulated HPF-a cells was significantly down-regulated (P <0.05); the CCK-8 assay and cell scratch assay showed that the down-regulation of hsa_circUCK2 gene significantly inhibited the proliferation and migration of HPF-a cells (P<0.01). In the animal experiments, the real-time fluorescence quantitative PCR results showed that among the detected organs, mmu_circ_0000115 was significantly knocked down only in the lung tissues (P<0.0001); the Western blot results showed that knocking down mmu_circ_0000115 significantly reduced the COL1A2 protein expression level when compared with the SiO2+si-con group (P<0.0001); the Sirius red results showed that knocking down mmu_circ_0000115 significantly reduced collagen production and deposition in lung tissues of mice in the model group. Conclusion Knockdown of hsa_circUCK2 inhibits fibroblast activation and reduces collagen deposition in lung fibrosis model mice. It is suggested that the hsa_circUCK2 is involved in the process of pulmonary fibrosis and may be a potential therapeutic target for pulmonary fibrosis.

15.
Article in Zh | WPRIM | ID: wpr-1019372

ABSTRACT

Purpose To explore the application and clini-copathological significance of molecular classification in endome-trial cancer(EC)of WHO(2020)tumors of the female repro-ductive system.Methods Sixty-two EC patients were collected and categorized into four subgroups,namely POLE mutation type,mismatch repair deficient(MMRd)type,non-specific molecular spectrum(NMSP)type,and p53 mutation type,based on WHO molecular classification tested by PCR and im-munohistochemistry.The correlation among four molecular sub-groups and their clinicopathological features were analyzed.Re-sults The molecular classification was distributed as follows:3(4.8%)cases were POLE-mutated,15(24.2%)cases MMRd,36(58.1%)cases NSMP and 8(12.9%)cases p53 abnormal expression.There were no significant differences a-mong POLE-mutated and infiltration depth,grade,lymph vascu-lar space invasion and other pathological factors such as lymph node metastasis and FIGO stage(P>0.05).Among 15 patients with MMRd,the proportion of FIGO stage Ⅱ+Ⅲ significantly increased.One case showed abnormal overexpression of p53 pro-tein,while two cases showed complete loss of expression in MMRd subgroup.36 cases of NSMP were associated with low histopathological grade(Grade Ⅰ+Ⅱ)(P<0.05),and no significant differences were observed among NSMP and other clinicopathological factors(P>0.05).The p53 abnormal ex-pression in 8 cases was related to high histopathological grade(Grade Ⅲ)(P<0.05),and the rate of lymph node metastasis and FIGO stage Ⅱ+Ⅲ significantly increased in patients with p53 abnormal expression,and although the difference was not statistically significant(P>0.05).Conclusion The molecu-lar subgroups of EC have certain clinical application value,the cases with MMRd and p53 abnormal expression may have poor prognosis than these with POLE-mutated and NSMP.

16.
Neuroscience Bulletin ; (6): 171-181, 2024.
Article in English | WPRIM | ID: wpr-1010653

ABSTRACT

Even though retinal images of objects change their locations following each eye movement, we perceive a stable and continuous world. One possible mechanism by which the brain achieves such visual stability is to construct a craniotopic coordinate by integrating retinal and extraretinal information. There have been several proposals on how this may be done, including eye-position modulation (gain fields) of retinotopic receptive fields (RFs) and craniotopic RFs. In the present study, we investigated coordinate systems used by RFs in the lateral intraparietal (LIP) cortex and frontal eye fields (FEF) and compared the two areas. We mapped the two-dimensional RFs of neurons in detail under two eye fixations and analyzed how the RF of a given neuron changes with eye position to determine its coordinate representation. The same recording and analysis procedures were applied to the two brain areas. We found that, in both areas, RFs were distributed from retinotopic to craniotopic representations. There was no significant difference between the distributions in the LIP and FEF. Only a small fraction of neurons was fully craniotopic, whereas most neurons were between the retinotopic and craniotopic representations. The distributions were strongly biased toward the retinotopic side but with significant craniotopic shifts. These results suggest that there is only weak evidence for craniotopic RFs in the LIP and FEF, and that transformation from retinotopic to craniotopic coordinates in these areas must rely on other factors such as gain fields.


Subject(s)
Animals , Macaca , Visual Fields , Frontal Lobe/physiology , Eye Movements , Brain
17.
ISA Trans ; 74: 217-228, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29395132

ABSTRACT

Based on extended state observer, a novel and practical design method is developed to solve the distributed cooperative tracking problem of higher-order nonlinear multiagent systems with lumped disturbance in a fixed communication topology directed graph. The proposed method is designed to guarantee all the follower nodes ultimately and uniformly converge to the leader node with bounded residual errors. The leader node, modeled as a higher-order non-autonomous nonlinear system, acts as a command generator giving commands only to a small portion of the networked follower nodes. Extended state observer is used to estimate the local states and lumped disturbance of each follower node. Moreover, each distributed controller can work independently only requiring the relative states and/or the estimated relative states information between itself and its neighbors. Finally an engineering application of multi flight simulators systems is demonstrated to test and verify the effectiveness of the proposed algorithm.

18.
Chinese Critical Care Medicine ; (12): 524-527, 2023.
Article in Zh | WPRIM | ID: wpr-982626

ABSTRACT

OBJECTIVE@#To observe the correlation between early fluid resuscitation and prognosis in patients with severe acute pancreatitis (SAP).@*METHODS@#SAP patients admitted to the department of critical care medicine of the People's Hospital of Chuxiong Yi Autonomous Prefecture of Yunnan Province from June 2018 to December 2020 were enrolled and analyzed retrospectively. All patients were given the routine treatment according to their condition and relevant diagnostic According to their different prognosis, enrolled patients were divided into death group and survival group. The differences in gender, age, acute physiology and chronic health evaluation II (APACHE II) and Ranson score on admission between the two groups were analyzed. Taking 24 hours as an observation day, the fluid inflow, outflow, and net balance at the first, second, and third 24 hours after admission were recorded, and the ratio of the fluid inflow at the first 24 hours to the total fluid inflow in 72 hours (FV24 h-1 st) was calculated as a study index. Using 33% as the standard, compare the proportion of patients in the two groups who achieved FV24 h-1 st < 33%. The differences of various indicators between the two groups were compared, and the effect of early fluid balance on the prognosis of SAP patients was analyzed.@*RESULTS@#Eighty-nine patients were included in the study (41 in the death group, 48 in the survival group). There were no statistically significant differences on age (years old: 57.6±15.2 vs. 49.5±15.2), gender (male: 61.0% vs. 54.2%), APACHE II score (18.0±2.4 vs. 17.3±2.3), and Ranson score (6.3±1.4 vs. 5.9±1.2) between the death group and the survival group at the time of admission on the intensive care unit (ICU) (all P > 0.05). The fluid intake of the death group in the first 24 hours, the second 24 hours and the third 24 hours after admission to ICU was significantly higher than that of the survival group, and the difference was statistically significant (mL: 4 138±832 vs. 3 535±1 058, 3 883±729 vs. 3 324±516, 3 786±490 vs. 3 212±609, all P < 0.05), and the fluid inflow in the death group at the first 24 hours was greater than 4 100 mL. After treatment, the fluid outflow of the death group at the three 24-hour periods after admission on the ICU was an increasing trend, but it was still significantly less than that of the survival group at the three 24-hour periods (mL: 1 242±465 vs. 1 795±819, 1 536±579 vs. 2 080±524, 1 610±585 vs. 2 932±752, all P < 0.01). Due to the fact that the total fluid inflow and total fluid outflow in the three 24-hour periods in the death group were more than those in the survival group, the net fluid balances in the three 24-hour periods in the death group were still significantly more than those in the survival group finally (mL: 2 896±782 vs. 1 740±725, 2 347±459 vs. 1 243±795, 2 176±807 vs. 338±289, all P < 0.01). There was no difference in FV24 h-1 st between the death group and survival group [FV24 h-1 st > 33%: 56.1% (23/41) vs. 54.2% (26/48), P > 0.05].@*CONCLUSIONS@#Fluid resuscitation is an important method for early treatment of SAP, but it also has many adverse reactions. Fluid resuscitation indexes such as fluid inflow, outflow, net balance, and FV24 h-1 st within 24 to 72 hours after admission are related to the prognosis of patients with SAP, and can be used as indicators to evaluate the prognosis of SAP. The optimized fluid resuscitation strategy can improve the prognosis of patients with SAP.


Subject(s)
Humans , Male , Acute Disease , Retrospective Studies , Pancreatitis , China , Prognosis , Water-Electrolyte Balance
19.
Chinese Journal of Orthopaedics ; (12): 172-178, 2023.
Article in Zh | WPRIM | ID: wpr-993425

ABSTRACT

Objective:To identify the anatomical distribution of and factors related to single-segment osteoporotic vertebral compression fractures (OVCF).Methods:The radiology and clinical data of 944 patients with single-segment OVCF hospitalized in Zhongda Hospital Southeast University between June 2016 and October 2020 were retrospectively analyzed, including 175 males and 769 females, aged 72.1±9.6 years (range, 45-97 years). The anatomical distribution of OVCF was quantified. The demographics, comorbidity profile, spine trauma, back pain duration, vertebral compression degree, and bone mineral density of the OVCF patients in different anatomical segments were summarized and compared.Results:Of the 944 single-segment OVCF, 864 were located in the lower thoracic and lumbar spine that peaked at L 1 (Modal-1 group), and 80 were located in the middle and upper thoracic spine (Modal-2 group) that peaked at T 7, demonstrating an asymmetric bimodal distribution. The difference in the female/male ratio between the two groups was insignificant (χ 2=0.06, P=0.803). Patients in Modal-2 were aged 75.0±9.8 years and on average older than the patients (aged 71.8±9.6 years) in Modal-1 ( t=2.78, P=0.005). The female patients in Modal-2 (aged 75.0±9.6 years) were significantly older than that (aged 71.2±9.3 years) in Modal-1 ( t=3.17, P=0.002). The ratio of back pain duration for <1 week in Modal-2 (43.8%) was lower than that in Modal-1 (60.2%), and the ratio of back pain for 1-weeks (28.8%) was significantly higher than that (15.5%) in Modal-1 (χ 2=11.50, P=0.009). The most frequently reported spine traumas in Modal-2 (50.0%) were heavy lifting injury, lumbar sprain, and strenuous cough, which were significantly different from and less apparent than the fall on ground or crush injury to the spine (64.1%) in Modal-1 (χ 2=60.71, P<0.001). The anterior to posterior height ratio of the fractured vertebrae in Modal-2 was 0.78±0.13, 0.83±0.14, 0.84±0.13, and 0.78±0.18 in the OVCF patients complaining of back pain for <1 week, 1-weeks, 2-weeks, and >4 weeks respectively, showing no significant difference between groups ( F=1.01, P=0.009). In Modal-1, the anterior to posterior height ratio of the fractured vertebrae was lower in the OVCF patients complaining of back pain for 2-weeks (0.80±0.15) and >4 weeks (0.77±0.19) than in those with back pain for <1 week (0.85±0.11) and 1-weeks (0.86±0.14), with sinificant differences ( P<0.05). 32.4% (306/944) of the OVCF patients had one of the following geriatric comorbidities: hypertension, diabetes mellitus, coronary heart disease, cerebral infarction, and chronic obstructive pulmonary disease. The OVCF patients in Model-2 had higher comorbidity of coronary heart disease (21.3%) and cerebral infarction (36.3%) than those in Model-1 (11.6% and 20.3%). Bone mineral density information was available from 371 patients (308 females). In the age groups of <70, 70-, and >80 years, no significant difference was detected in the T-score values of the lumbar spine or hip joint between the OVCF patients in Model-1 and Model-2 ( F=0.13, P=0.880; F=0.62, P=0.538). Conclusion:Single-segment OVCF feature an asymmetric bimodal distribution that is demarcated by the T 10 vertebrae. The distribution pattern is not determined by gender or baseline bone mineral density but highlights the risk of mechanical stress and vertebral fragility within a specific segment. OVCF in the middle and upper thoracic spine is less frequent but common in older patients with higher comorbidity of coronary heart disease and cerebral infarction, which tend to be caused by less apparent spine trauma and maintain vertebral compression but complain of long back pain duration.

20.
Zhongguo zhenjiu ; (12): 439-443, 2023.
Article in Zh | WPRIM | ID: wpr-980742

ABSTRACT

OBJECTIVE@#To detect the body surface temperature of the relevant back-shu points in patients with chronic persistent asthma by infrared thermal imaging technology, and observe the specific changes of the body surface temperature of the relevant back-shu points under the condition of lung disease.@*METHODS@#Forty-five patients with chronic persistent asthma (observation group) and 45 healthy subjects (control group) were selected. The body surface temperature of bilateral Feishu (BL 13), Geshu (BL 17), Pishu (BL 20) and Shenshu (BL 23) were measured by BK-MT02A medical infrared thermography.@*RESULTS@#The body surface temperature of bilateral Feishu (BL 13), Geshu (BL 17), Pishu (BL 20) and Shenshu (BL 23) in the observation group was higher than that in the control group (P<0.01, P<0.05). The body surface temperature of bilateral Feishu (BL 13) and Geshu (BL 17) was higher than that of ipsilateral Pishu (BL 20) and Shenshu (BL 23) in the two groups (P<0.01, P<0.05). There was no statistically significant difference in body surface temperature between ipsilateral Feishu (BL 13) and Geshu (BL 17), between ipsilateral Pishu (BL 20) and Shenshu (BL 23) (P>0.05).@*CONCLUSION@#The pathological increase of body surface temperature of Feishu (BL 13), Geshu (BL 17), Pishu (BL 20) and Shenshu (BL 23) in patients with chronic persistent asthma indicates that above acupoints have specificity in reflecting lung diseases. The Feishu (BL 13) and Geshu (BL 17), which have significantly increased body surface temperature, not only provide objective basis for the pathological pathogenesis of "deficiency in origin and excess in symptom" in patients with chronic persistent asthma, but also reflect the different expressions of different acupoints on the same meridian for the lung diseases.


Subject(s)
Humans , Temperature , Asthma/diagnostic imaging , Meridians , Acupuncture Points , Acupuncture Therapy/methods
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