Deep brain stimulation electrode modeling in rats.

Deep Brain Stimulation (DBS) is an efficacious treatment option for an increasing range of brain disorders. To enhance our knowledge about the mechanisms of action of DBS and to probe novel targets, basic research in animal models with DBS is an essential research base. Beyond nonhuman primate, pig, and mouse models, the rat is a widely used animal model for probing DBS effects in basic research. Reconstructing DBS electrode placement after surgery is crucial to associate observed effects with modulating a specific target structure. Post-mortem histology is a commonly used method for reconstructing the electrode location. In humans, however, neuroimaging-based electrode localizations have become established. For this reason, we adapt the open-source software pipeline Lead-DBS for DBS electrode localizations from humans to the rat model. We validate our localization results by inter-rater concordance and a comparison with the conventional histological method. Finally, using the open-source software pipeline OSS-DBS, we demonstrate the subject-specific simulation of the VTA and the activation of axon models aligned to pathways representing neuronal fibers, also known as the pathway activation model. Both activation models yield a characterization of the impact of DBS on the target area. Our results suggest that the proposed neuroimaging-based method can precisely localize DBS electrode placements that are essentially rater-independent and yield results comparable to the histological gold standard. The advantages of neuroimaging-based electrode localizations are the possibility of acquiring them in vivo and combining electrode reconstructions with advanced imaging metrics, such as those obtained from diffusion or functional magnetic resonance imaging (MRI). This paper introduces a freely available open-source pipeline for DBS electrode reconstructions in rats. The presented initial validation results are promising.

Determination of the content of residual solvents in Haikesu I by head-space gas chromatography.

OBJECTIVE: To explore the usefulness of head-space gas chromatography for the determination of methanol and ethanol in Haikesu I,a raw material of artificial musk. METHODS: The determination was performed on HP-5(30 m×0.53 mm,5 Μm)capillary column with an hydrogen flame ionization detector. The solvent was dimethyl sulfoxide and the internal standard was acetone. The injector temperature and the detector temperature were controlled at 180 ℃ and 250 ℃,respectively. The carrier gas was nitrogen. The containers of head-space injector were preheated at 90 ℃ for 15 minutes. The column temperature was programmed raised,which achieved baseline separation of the components. RESULTS: The results showed a good linear relationship for methanol and ethanol in their linearity range;and the limit of detection was 0.8 and 1.0 Μg/ml,respectively. The precision and average recoveries were satisfactory. CONCLUSION: The head-space gas chromatography is simple,rapid,and precise technique for the measurement of residual solvents in Haikesu I.

Determination of the content of residual solvents in Haikesu 2 by head-space gas chromatography.

OBJECTIVE: To determine ethylacetate and petroleum ether(60-90 ℃)in Haikesu 2,which is one of the raw materials of artificial musk,using the head-space gas chromatography. METHODS: The determination was performed on HP-5(30 m×0.53 mm,5 Μm)capillary column with an hydrogen flame ionization detector. The solvent was dimethyl sulfoxide and the internal standard was methanol. The injector temperature and the detector temperature were controlled at 180 ℃ and 250 ℃,respectively. The carrier gas was nitrogen. The containers of head-space injector were preheated at 90 ℃ for 15 minutes. The column temperature was programmed raised,which achieved baseline separation of the components. RESULTS: The results showed a good linear relationship for ethylacetate and petroleum ether(60-90 ℃)in their linearity range;and the limit of detection was 0.7 and 0.3 Μg/ml,respectively. The good precision and good average recoveries were satisfactory. CONCLUSION: The head-space gas chromatography is simple,rapid,and precise technique for the measurement of residual solvents in Haikesu 2.

Quantum-confined photoluminescence from Ge(1-x)Sn(x)/Ge superlattices on Ge-buffered Si(001) substrates.

We report the first observation of room-temperature quantum-confined photoluminescence (PL) from low-dimensional Ge(1-x)Sn(x)/Ge superlattices (SLs) up to a high Sn content of 6.96%. Both direct and indirect emissions associated with the interband transitions between minibands in the conduction bands and valence band were observed at room temperature. As the Sn content is increased, the energy difference between the lowest direct and indirect transitions is reduced, indicating an effective modification of the band structure desired for optoelectronics. The integrated PL intensity ratio of direct to indirect recombinations is significantly enhanced with increasing Sn content due to the reduced Γ-L energy separation and quantum confinement effect. Those results suggest that Sn-based low-dimensional structures are promising material for efficient Si-based lasers.

[Experiences in prevention and treatment of human rabies with acupuncture and moxibustion in ancient time].

By consulting the literatures relevant with the prevention and treatment of human rabies from Tang Dynasty to Qing Dynasty, it was discovered that rabies was caused by wind toxin in mad dog injuring human being. The pathogenesis of rabies was the invasion of dog toxin into the heart. The latent period was ranged from 7 to 100 days. Acupuncture-moxibustion, bloodletting, cupping and other therapies could be used in treatment. But of those different therapies, the various moxibustion methods achieved unique efficacy on the disease.