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With the representative volume element, the random circular and hexagon models of explosive particles were set up in finite element software-ANSYS. Numerical simulation was implemented to study the effective elastic modulus of polymer-bonded explosives (PBXs). The prediction of effective elastic modulus agreed well with the experimental results. The effects of properties, volume fraction, shape and gradation of explosive particles as well as the properties of binder on the effective elastic modulus of PBXs were studied. The results show that the particle's size and shape have a minor influence on the effective elastic modulus of PBXs; however, the gradation of explosive particles play a major role in elastic modulus of PBXs. Results also show that the effective elastic modulus of PBXs increase with the increase of volume fraction and elastic modulus of explosive particles. At the higher volume fraction of explosive particles, the property of particles plays an important role in the effective elastic modulus of PBX. The volume fraction of binder is small; however, the elastic modulus of binder also has an obvious effect on the effective elastic modulus of PBX. [ABSTRACT FROM AUTHOR]

There still remains a large gap between theory and practice of Agent technology. In order to enrich the ability of Agent for easy realization, this paper defined a mental model of E-Agent with the concept from event condition action (ECA) rule. It designed the Agent description language and gave the interpretation loop of E-Agent. The proposed Agent system includes a visual model tool and a running environment. E-Agent can be easily used and modeled in a visual way. [ABSTRACT FROM AUTHOR]

Optical emission spectroscopy (OES) was used to detect the plasma distribution during the depositing process of diamond films with hot filament chemical vapor deposition (HFCVD) method using acetone as carbon source. The surface and cross section of deposited diamond films were characterized by scanning electron microscopy (SEM) and their quality was tested with Raman spectroscopy. OES results showed that the intensity of active species near the center is higher than that in marginal area in the case of linear array of hot filament. It is because of the higher temperature and stronger cracking ability near the filament. The variety of the characteristic peak intensity in central region is more gently than that of the plasma ball. Thermal radiation decreased when the distance from the hot filament increases, which results in less CH，CO groups cracked from acetone, lower intensity of Hα，Hβ excited by hydrogen and higher concentration of C2 group produced by reaction. SEM and Raman results showed that the quality of deposited diamond films deteriorated when the distance between hot filament and substrate varies from 4.5, 5.5 to 6.5 mm, which matches well with OES results.

Objective: To explore the effects of basic fibroblast growth factor (bFGF) on human bone marrow mesenchymal stem cell (hBMMSC) damaged by irradiation and its underlying mechanisms., Methods: hBMMSC was irradiated with 0, 6, 12 Gy X ray, then flow cytometry, cell counting kit-8 (CCK-8), Western blot and alizarin red staining were used to detect the effects of X ray on apoptosis, proliferation and osteogenic differentiation of hBMMSC; 0, 1, 5, 10, 20 ng/ml bFGF was added to hBMMSC irradiated with X ray for selecting the suitable bFGF reaction concentration; then the Western blot was used to detect the expression of PDGFRα so as to evaluate whether the expression of PDGFRα participated in bFGF-mediated recovery of hBMMSC proliferation and osteogenic differentiation after irradiation., Results: The proliferation and osteogenic differentiation of hBMMSC decreased remarkably after irradiation. bFGF promoted the recovery of proliferation and osteogenic differentiation of irradiated hBMMSC compared with untreated irradiated hBMMSC (P < 0.05); 5 ng/ml bFGF was identified as the optimal concentration. A significant difference in the number of apoptotic cells could be detected only between the 0 Gy group and 12 Gy group at the 24 h time point, while no differences were detected at later time points. Irradiated hBMMSC showed remarkable decrease of PDGFRα expression, while the PDGFRα expression increased after bFGF was added., Conclusion: Irradiation dose not show significant effect on apoptosis of hBMMSC, but the bFGF displays a effect on repairing the irradiation damage of hBMMSC and promotes the recovery of hBMMSC proliferation and osteogenic differentiation. The damage of hBMMSC proliferation and osteogenic differentiation associates with downregulation of PDGFRα expression induced by irrediation. PDGFRα involves in repairing effect of bFGF on irradiation damage of hBMMSC.

The intracellular trafficking and subcellular distribution of exogenous gene is very important for gene delivery. A successful gene vehicle should overcome various barriers including endosomal membrane barriers to delivery gene to the target organelle. Traditional nonviral vehicle is unable to avoid endosomal pathway efficiently, so the efficiency of gene delivery is low and the application of gene drugs is limited. In order to achieve efficient nonviral gene delivery, a lot of researches based on endosomal escape have been carried out and some agents with the function of endsomal escape have been found. These agents facilitate the endsomal escape via various mechanisms, such as fusion into the lipid bilayer of endosomes, pore formation in the endosomal membrane, proton sponge effect and photochemical methods to rupture the endosomal membrane. In this review, various reported strategies for endsomal escape are described according to the escape mechanisms, and their applications in intracellular gene delivery are also discussed.

Aim: To explore the clinical value of serum soluble intercellular adhesion molecule-1 (sICAM-1) in patients with primary hepatocellular carcinoma (PHC) and its relationship with liver fibrosis., Methods: The serun sICAM-1, PC III, IV-C, LN and HA level of 45 cases of patients with PHC, 30 cases of benign tumor and 35 cases of healthy people were determined by ELISA, the relationship between sICAM-1 and liver fibrosis was analyzed., Results: The serum sICAM-1, PC III, IV-C, LN and HA levels of the PHC group were significantly higher than that of the benign tumor group and normal control group, compared the difference was significant (P<0.05); The serum markers was no significant difference between the benign tumor group and normal control group (P>0.05); The serum sICAM-1 was positively correlated with the PC III, IV-C, LN and HA (γ= 0.683, 0.575, 0.573 and 0.539, P<0.05)., Conclusion: Detection of serum sICAM-1 has important clinical significance for assessing the PHC patient's condition, early diagnosing and treating liver cancer.

Objective: To study the effect of electroacupuncture on nitric oxide synthase (NOS) in rats with cerebral ischemia-reperfusion injury., Methods: Focal cerebral ischemia-reperfusion model was established using modified intravascular suture technique. The NO content in the brain tissue was detected by nitrite reduction and the expressions of nNOS and iNOS were detected by immunohistochemistry. Eighty rats in this experiment were divided into the normal group, the cerebral ischemia-reperfusion injury model group (as the model group), the cerebral ischemia-reperfusion injury + electroacupuncture group (as the acupuncture group), and the cerebral ischemia-reperfusion injury + phosphatidylinositol 3 kinase (PI3-K) inhibitor group (as the inhibitor group). Each group consisted of twenty rats. Five microL PI3-K inhibitor LY294002 (400 microL) was slowly injected at the lateral cerebral ventricle of rats in the inhibitor group at a constant speed using microinjector according to Konig Klippel atlas of the stereotaxis instrument. Shuigou (DU26) and Chengjiang (RN24) were selected to determine levels of NO and NOS., Results: After 24-h ischemia-reperfusion, the NO levels of the hippocampus and the cerebral cortex increased abnormally, and the expressions of nNOS and iNOS increased, showing significant difference when compared with those of the normal group (P<0.05). By electroacupuncture at Shuigou (DU26) and Chengjiang (RN24), the ischemic cerebral ischemia-reperfusion injury neuron loss was inhibited. Meanwhile, the high levels of NO, nNOS and iNOS in the cerebral cortex and the hippocampus were significantly inhibited (P<0.05). The abnormally increased expressions of nNOS and iNOS were reversed, showing significant difference when compared with the model group (P<0.05). But when compared with the normal group, there was no significant difference (P>0.05). The effects of electroacupuncture reversed the abnormally increased NO levels of the hippocampus and the cerebral cortex and expressions of nNOS and iNOS after LY294002 oppressed anti-PI3K to block the TrkA acceptor circuit. The NO levels of the hippocampus and the cerebral cortex and expressions of nNOS and iNOS increased again, showing significant difference when compared with the acupuncture group (P<0.05)., Conclusions: Acupuncture fought against cerebral ischemia and reperfusion in the loss of neurons, at the same time, the abnormal regulation of NOS had reverse effect partly through TrkA/PI3K mediated signal transduction pathway.

Objective: To study and compare the main chemical constituents of Sarcandra glabra and qingrexiaoyanning capsules which were extracted by acetic ether., Methods: The sample solution were analyzed by a Zorbax C18 column with a gradient mobile phase composed of acetonitrile and 0.1% formic acid solution. Both UV and mass spectrometry detector were used simutaneously, full-scan detection mode was evaluated for the identification of all LC peaks., Results: We analyzed the mass spectrum of every LC peak and identified 26 molecular mass from the ion chromatogram of Sarcandra glabra extraction and 16 molecular mass from the extractions of qingrexiaoyanning capsule. 5 compounds were identified., Conclusion: High performance liquid chromatography-mass/mass spectrometry has special advantages on analyzing the chemical constituents of traditional Chinese medicine.

Objective: To develop a high-performance liquid chromatographic-tandem mass/mass spectrometric method to determine the concentration of 1-deoxynojirimycin (1-DNJ) in mulberry leaves., Methods: 1-deoxynojirimycin was separated on an SHIMADZU HRC-NH2 column with the mobile phase consisting of acetonitrile and 0.1% formic acid. The mass spectrometric system equipped with a atmospheric pressure chemical ionization (APCI) interface was operated in Multiple Reaction Monitoring (MRM) mode., Results: The retention time of 1-deoxynojirimycin was 2.87 min, and the calibration curve was linear over a concentration range from 482 microg/L to 2410 microg/L, the average recovery was 95.8%. The detection limit was 53.6 microg/L., Conclusion: The method is selective and sensitive for determining 1-deoxynojirimycin in mulberry leaves.

The effect of Rhizoma curcumae oil on the learning and memory in rats exposed to chronic hypoxia and the possible mechanisms were investigated. The rats were divided randomly into 5 groups (14 animals in each group): control, chronic hypoxia, chronic hypoxia with low (5 mg/kg body weight), middle (10 mg/kg body weight) and high (20 mg/kg body weight) concentrations of Rhizoma curcumae oil injection. The animals undergoing chronic hypoxia were exposed to hypoxia in a hypoxic chamber containing 10% O(2) and 5% CO(2) for 10 h/d, lasting 28 d. Morris water maze (MWM) test was used to obtain the scores of leaning and memory. The superoxide dismutase (SOD) activity and malonaldehyde (MDA) content were determined in the serum and hippocampus as well as [Ca(2+)](i) in the hippocampus. The expression of phosphorylated Ca(2+)/calmodulin-dependent protein kinase II (p-CaMKII) in the hippocampus was evaluated by using immunohistochemistry and Western blot. Compared with the control group, the chronic hypoxia group showed the following changes: (1) The escape latency to the hidden platform was remarkably prolonged (P<0.05); (2) The content of MDA and [Ca(2+)](i) were obviously higher, but the activity of SOD and the expression of p-CaMKII were significantly lower (P<0.05, P<0.01). Compared with the chronic hypoxia group, groups with Rhizoma curcumae oil injection had the following changes: (1) The escape latency to the hidden platform was remarkably shorter in 10, 20 mg/kg body weight groups (P<0.05); (2) The content of MDA and [Ca(2+)](i) were markedly decreased in 5, 10, 20 mg/kg body weight groups (P<0.05, P<0.01), but the activity of SOD in the serum and the expression of p-CaMKII were significantly higher in 10, 20 mg/kg body weight groups (P<0.05, P<0.01). The results showed that the capacity of learning and memory was degraded following chronic hypoxia. The decrease in MDA content and [Ca(2+)](i) and (or) the increase in SOD activity and p-CaMKII expression might participate in the enhancing effect on learning and memory induced by Rhizoma curcumae oil.

Objective: To establish a method for determining isofraxidin concentrations in Sarcandra glabra and Qingrexiaoyanning capsules with high-performance liquid chromatographic-mass spectrometry., Methods: Isofraxidin was extracted from Sarcandra glabra and Qingrexiaoyanning capsules with acetic ether and chloroform, respectively, and separated by isocratic reversed-phase chromatography. The mass spectrometric system was operated in multiple reaction monitoring mode. A pair of ions: precursor ion m/z 223 with product ion m/z 162 were chosen for the quantification of the analyte., Results: The retention time of isofraxidin was 6.60 min, and the calibration curve was linear over a concentration range from 484 to 9 680 ng/ml. The average recovery was 96.7% and RSD 4.49%, with detection limit of 1 ng/ml., Conclusion: The method is rapid, selective and sensitive for determining isofraxidin in Sarcandra glabra and Qingrexiaoyanning capsules.

Objective: To determine the total content of alkaloids from Rhizoma coptidis in the traditional Chinese medicine prescription Gegenqinlian., Methods: The extract of Gegenqinlian decoction and powder of the minipills were respectively purified with alumina column chromatography, and the total alkaloid content of Rhizoma coptidis in these preparations was determined using ultraviolet spectrophotometry at 350 nm., Results: The total alkaloid content was 32.4 mg/g in the aqueous extract of Gegenqinlian decoction and 19.6 mg/g in Gegenqinlian minipills, with a recovery rate of 98.1% (RSD=2.9%)., Conclusion: The method we employed yields accurate and stable results with much sensitivity for quality control of Gegenqinlian minipills, and also provides reference for study of Gegenqinlian prescription and other prescriptions that contain Rhizoma coptidis.

Objective: To develop a method for determining urinary citrate and oxalate using high-performance capillary electrophoresis., Methods: Capillary electrophoresis with indirect ultraviolet (UV) detection was performed for determining urinary citrate and oxalate. Sodium hromate was used as the UV-absorbing background electrolyte., Results: Citrate and oxalate had a migration time of 3.76 min and 3.14 min respectively. The calibration curves were linear within a limit of about 2 microg/ml for citrate and about 1 microg/ml for oxalate. The recovery rates of citrate and oxalate were 97.53% and 99.11% respectively., Conclusion: This method is simple, accurate and at low cost for determining citrate and oxalate in the urine.