[en] Objective: To study the changes in activities of acetylcholine esterase (AChE), acid phosphatase (ACP) and succinic dehydrogenase (SDH) in diaschisis area after focal cerebral ischemia. Methods: The activities of AChE, ACP and SDH in diaschisis areas which were defined by cerebral blood flow autoradiography in a rat model of right middle cerebral artery occlusion (MCAO) were observed using enzymatic histochemistry. Results: With focal cerebral ischemia, there were no changes in AChE and ACP activities in the diaschisis areas, but SDH activity decreased. Conclusion: In the diaschisis areas the function of cholinergic system and lysosome was not affected, but metabolic activity of mitochondria decreased

[en] Objective: To study the location of ⁹⁹Tc^m-HMPAO in neurons. Methods: Cerebral blood flow autoradiography was done in 3 normal rats all 11 rats with right middle cerebral artery occlusion (MCAO) and observed with light and electron microscope. Results: ⁹⁹Tc^m-HMAPO silver particles were observed in the cytoplasm and processes of normal neurons and the distribution was not even among different neutrons. In MCAO rats, the distribution of ⁹⁹Tc^m-HMPAO silver particles showed diffuse decrease in ischemic penumbra and almost disappeared in the infarcted core. Conclusion: The retention of ⁹⁹Tc^m-HMPAO in neurons might be correlated with the metabolic process taking place in cytoplasm

[en] In this paper, we mainly propose a chaotic secure communication scheme which is based on the synchronization of double-layered and multiple complex dynamical networks. Compared with the previous chaotic secure communication schemes, in which only two chaotic systems or just a single-layer network composed of multiple chaotic systems is used, the introduction of a double-layered and multiple complex networks model composed of many encryption/encryption units can not only reflect the complex characteristics of different nodes, but also can improve the complexity and security of information encryption. By using a clustering method, nodes with the same characteristics belong to the same subnet, while the nodes with different characteristics belong to different ones. The subnets in the transmitter and receiver are one-to-one correspondence and form a pair of matching subnets, but the node size of each subnet can be inconsistent. Each subnet is only responsible for encrypting a certain part of information, and thus, the synchronization between each pair of matching subnets plays a crucial role on the correct recovery of information. Multiple encryption/decryption units operating in parallel way can speed up the encryption of information, and the key space can grow with the number of nodes in the transmitter. The proposed scheme utilizes the chaotic signals generated by many chaotic systems as the key sequences and adopts the one-time-one-cipher encryption method. Moreover, this scheme is not subject to the constraint that the amplitude of the encrypted signal should be much smaller than that of the chaotic signal, and it is particularly suitable for the big data encryption. Both theoretical analysis and numerical simulation demonstrate the feasibility and effectiveness of the proposed scheme.

[en] The targets and the use of weapons are complicated on attacking ground target, Besides, the weapon-target assignment (WTA) research is extremely difficult and lacking. For a timely and rational WTA scheme can not only help to seize fleeting war opportunities, but also optimize the use of weapon resources to maximize the battlefield benefits with minimum costs, this article builds a mathematical model and uses genetic algorithm (GA) to find the optimal WTA result. But the algorithm is difficult to prepare better initial population because of the random assignment of variables which results in undesirable optimization results. To overcome the challenge in initializing GA, this article puts forward a variable probability assignment technique. This technique first uses feasible solutions to determine the probability distribution of the variable values, then, uses probability assignment mode to replace the stochastic uniform assignment mode to initialize variables, and produces the initial population individual close to the optimal individual with certainty. The simulation calculation shows that the improved GA can effectively solve the WTA problem of the large scale ground targets attacking with better performance. (paper)

[en] In this paper, the total ionizing dose (TID) and single-event effect (SEE) in vertical channel double-gate (DG) nMOSFETs are comprehensively investigated. Due to the vertical channel structure and the excellent gate control capability, the vertical channel DG transistor is relatively resistant to TID and transient ionization effect. However, the dc characteristics of vertical channel DG device are very sensitive to permanent damage induced by a few ions hitting the device. The on-state current and transconductance of the vertical channel DG MOSFETs show significant degradation after exposure to heavy ions, which is attributed to the formation of displacement damage in the channel. As the device feature size scales down to the deca-nanometer regime, the influence of permanent damage induced by a few ions striking the device static performance cannot be ignored and should be seriously considered in radiation-hardened technologies. (paper)

[en] This paper mainly reports the permanent impact of displacement damage induced by heavy-ion strikes on the deep-submicron MOSFETs. Upon the heavy ion track through the device, it can lead to displacement damage, including the vacancies and the interstitials. As the featured size of device scales down, the damage can change the dopant distribution in the channel and source/drain regions through the generation of radiation-induced defects and thus have significant impacts on their electrical characteristics. The measured results show that the radiation-induced damage can cause DC characteristics degradations including the threshold voltage, subthreshold swing, saturation drain current, transconductance, etc. The radiation-induced displacement damage may become the dominant issue while it was the secondary concern for the traditional devices after the heavy ion irradiation. The samples are also irradiated by Co-60 gamma ray for comparison with the heavy ion irradiation results. Corresponding explanations and analysis are discussed

[en] Objective: To investigate the feasibility of thrombolytic therapy for cerebral arteries in experimental pigs under real-time MR imaging guidance. Methods: Ten domestic female pigs (produced in U.S.A.) were enrolled in this study. After puncturing femoral artery with percutaneous technique, the bilateral ascending pharyngeal arteries were catheterized with 3 F active MR-tracking microcatheter under the guidance of real-time MR imaging. Then, aged thrombi were injected via the microcatheter to occlude the pharyngeal arteries. After 30-60 minutes, 500,000-750,000 units of urokinase were infused through the microcatheter into either one of the occluded ascending pharyngeal arteries for thrombolysis. Intraarterial contrast enhanced MRA and T1 fat suppressed coronal MR images were obtained to assess the vessel occlusion and the results of thrombolysis. Results: MR angiography revealed that the major cerebral blood supply in pigs was obtained from the basicranial micro-vascular network which was formed by bilateral ascending pharyngeal arteries. Catheterization of ascending pharyngeal arteries via the femoral artery access was successfully performed in all 10 pigs under the guidance of real-time MR imaging. Both ascending pharyngeal arteries were totally occluded in all pigs after injection of aged thromboli. After urokinase infusion into the ascending pharyngeal arteries, the blood clots were resolved with re-established blood flow. Conclusion: It is feasible to perform thrombolytic therapy for cerebral arteries under real-time MR imaging guidance. (authors)

[en] Deep cryogenic treatment (DCT) in the phase transition region of austenite (A) to ferrite (F) is a novel process that can efficiently improve the content of martensite (M) and F of dual phase (DP) steel. In this work, microstructure transformation in DP structural steel treated by DCT was investigated in detail. Scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) were used to characterize the microstructure, alloy distribution, grain size, and orientation for the DP structural steel. The results demonstrated that DCT could effectively improve the yield ratio and mechanical properties of the tested steel. F and its large-angle significantly reduced the influence of fine-grain strengthening on the reduction of yield ratio. This research offered innovative technical support and theory guidelines for producing and studying such extraordinary strength-toughness DP steel with high strength and low yield ratio. (paper)

[en] To improve the biological performance of poly(ethylene glycol)-diacrylate (PEGDA) hydrogel as an injectable bone grafting scaffold, sodium methallyl sulphonate (SMAS) was incorporated into PEGDA hydrogel. The physiochemical properties of the resultant polymers were assessed via Fourier transform infrared spectroscopy (FTIR), swelling ratio, zeta potential, surface morphology, and protein adsorption analysis. MC3T3-E1 cells were seeded on the hydrogel to evaluate the effect of the sulphonated modification on their attachment, proliferation, and differentiation. The results of FTIR and zeta potential evaluations revealed that SMAS was successfully incorporated into PEGDA. With increasing concentrations of SMAS, the swelling ratio of the hydrogels increased in deionized water but stayed constant in phosphate buffered saline. The protein adsorption also increased with increasing concentration of SMAS. Moreover, the sulphonated modification of PEGDA hydrogel not only enhanced the attachment and proliferation of osteoblast-like MC3T3-E1 cells but also up-regulated alkaline phosphatase activity as well as gene expression of osteogenic markers and related growth factors, including collagen type I, osteocalcin, runt related transcription factor 2, bone morphogenetic protein 2, and transforming growth factor beta 1. These findings indicate that the sulphonated modification could significantly improve the biological performance of PEGDA hydrogel. Thus, the sulphonated PEGDA is a promising scaffold candidate for bone grafting.

[en] The effects of the physical damages induced by heavy ion irradiation on the performance of partially-depleted SOI devices are experimentally investigated. After heavy ion exposure, different degradation phenomena are observed due to the random strike of heavy ions. A decrease of the saturation current and transconductance, and an enhanced gate-induced drain leakage current are observed, which are mainly attributed to the displacement damages that may be located in the channel, the depletion region of the drain/body junction or the gate-to-drain overlap region. Further, PDSOI devices with and without body contact are compared, which reveals the differences in the threshold voltage shift, the drain-induced barrier lowing effect, the transconductance and the kink effect. The results may provide a guideline for radiation hardened design. (paper)