Anatomical knowledge of the structures to be targeted and of the circuitry involved is crucial in stereotactic functional neurosurgery. The present study was undertaken in the context of surgical treatment of motor disorders such as essential tremor (ET) and Parkinson’s disease (PD) to precisely determine the course and three-dimensional stereotactic localisation of the cerebellothalamic and pallidothalamic tracts in the human brain. The course of the fibre tracts to the thalamus was traced in the subthalamic region using multiple staining procedures and their entrance into the thalamus determined according to our atlas of the human thalamus and basal ganglia [Morel (2007) Stereotactic atlas of the human thalamus and basal ganglia. Informa Healthcare Inc., New York]. Stereotactic three-dimensional coordinates were determined by sectioning thalamic and basal ganglia blocks parallel to stereotactic planes and, in two cases, by correlation with magnetic resonance images (MRI) from the same brains prior to sectioning. The major contributions of this study are to provide: (1) evidence that the bulks of the cerebellothalamic and pallidothalamic tracts are clearly separated up to their thalamic entrance, (2) stereotactic maps of the two tracts in the subthalamic region, (3) the possibility to discriminate between different subthalamic fibre tracts on the basis of immunohistochemical stainings, (4) correlations of histologically identified fibre tracts with high-resolution MRI, and (5) evaluation of the interindividual variability of the fibre systems in the subthalamic region. This study should provide an important basis for accurate stereotactic neurosurgical targeting of the subthalamic region in motor disorders such as PD and ET.

AII amacrine cells have been found in all mammalian retinas examined and play an important role for visual processing under both scotopic and photopic conditions. Whereas ultrastructural investigations have provided a detailed understanding of synaptic connectivity, there is little information available with respect to quantitative properties and variation of cellular morphology. Here, we performed whole-cell recordings from AII amacrine cells in rat retinal slices and filled the cells with fluorescent dyes. Multi-photon excitation microscopy was used to acquire image stacks and after deconvolution, we performed quantitative morphological reconstruction by computer-aided manual tracing. We reconstructed and performed morphometric analysis on 43 AII amacrine cells, with a focus on branching pattern, dendritic lengths and diameters, surface area, and number and distribution of dendritic varicosities. Compared to previous descriptions, the most surprising result was the considerable extent of branching, with the maximum branch order ranging from approximately 10–40. We found that AII amacrine cells conform to a recently described general structural design principle for neural arbors, where arbor density decreases proportionally to increasing territory size. We confirmed and quantified the bi-stratified morphology of AII amacrine cells by analyzing the arborizations as a function of retinal localization or with Sholl spheres. Principal component and cluster analysis revealed no evidence for morphological subtypes of AII amacrines. These results establish a database of morphometric properties important for studies of development, regeneration, degeneration, and disease processes, as well as a workflow compatible with compartmental modeling.

Signal processing within the retina is generally mediated by graded potentials, whereas output is conveyed by action potentials transmitted along optic nerve axons. Among retinal neurons, amacrine cells seem to be an exception to this general rule, as several types generate voltage-gated Na + (Na v ) channel-dependent action potentials. The AII, a narrow-field, bistratified axon-less amacrine cell found in mammalian retinas, displays a unique process that resembles an axon initial segment (AIS), with expression of Na v channels colocalized with the cytoskeletal protein ankyrin-G, and generates action potentials. As the role of spiking in AIIs is uncertain, we hypothesized that the morphological properties of the AIS-like process could provide information relevant for its functional importance, including potential pre-and/or postsynaptic connectivity. For morphological analysis, we injected AII amacrine cells in slices with fluorescent dye and immunolabeled the slices for ankyrin-G. Subsequently, this enabled us to reliably identify AII-type processes among ankyrin-Glabeled processes in wholemount retina. We systematically analyzed the laminar localization, spatial orientation, and distribution of the AIS-like processes as a function of retinal eccentricity. In the horizontal plane, the processes displayed no preferred orientation and terminal endings were randomly distributed. In the vertical plane, the processes displayed a horizontal preference, but also ascended and descended into the inner nuclear layer and proximal inner plexiform layer, respectively. These results suggest that the AII amacrine AIS-like process is unlikely to take part in conventional synaptic connections, but may instead be adapted to respond to volume neurotransmission by means of extrasynaptic receptors.

SVC is a dynamic reactive compensator based on switching type HV electrical and electronic devices, well recognized as an effective means of resolving power quality problems. SVC is complex in structure, consisting of TCR valve sets, FC filter channel, etc. In particular, TCR valve set adopts thyristor serial connecting technology, and over 100 thyristors are adopted, which requires real-time status of devices in SVC to be monitored and uploaded, and even failures to be recorded. Therefore, the monitoring software becomes an important part in ensuring SVC safe operation. Combined with actual cases, this paper introduces a technology of using C++ Builder and Inter Base to design the static reactive compensator monitoring software. The user interface is elegant, with short development period, highly transplantable, and easily modified.