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This paper proposes a technique for applying LC resonance to a rectifier circuit of a self-excited wound-field rotor, which utilizes space harmonics for improving the variable flux function. The rotor magnetomotive force can be improved by setting the resonance frequency of the LC resonance circuit to a low speed rotation range. The adjustable speed drive characteristics and efficiency maps are demonstrated via a prototype. [ABSTRACT FROM AUTHOR]

Atlanto-occipital dislocation (AOD) is rarely seen in clinic because it is characteristically immediately fatal. With recent progress in the pre-hospital care, an increasing number of AOD survivors have been reported. However, because the pathophysiology of AOD is not clearly understood yet, the appropriate strategy for the initial management remains still unclear. We report a case of successful AOD treatment and describe important points in the management of this condition. It is important to note that abducens nerve palsy is a warning sign of AOD and that AOD can result in a life-threatening distortion of the arteries and the brain stem. We recommend the application of a halo vest to protect the patient's neural and vascular competence as the immediate initial step in the treatment of AOD. Horn's grading system is useful in assessing indications for surgery. Finally, when performing posterior fixation, C2 should be included because of the anatomy of the ligamentous architecture. [ABSTRACT FROM AUTHOR]

The combination of scanning tunnelling microscopy (STM) with optical excitation using ultrashort laser pulses enables us, in principle, to simultaneously obtain ultimate spatial and temporal resolutions. We have developed the shaken-pulse-pair-excited STM (SPPX-STM) and succeeded in detecting a weak time-resolved tunnelling current signal from a low-temperature-grown GaNAs sample. To clarify the underlying physics in SPPX-STM measurements, we performed optical pump-probe reflectivity measurements with a wavelength-changeable ultrashort-pulse laser. By comparing the results obtained from the two methods with an analysis based on the nonlinear relationship between the photocarrier density and tunnelling current, we obtained a comprehensive explanation that the photocarrier dynamics is reflected in the SPPX-STM signal through the surface photovoltage effect. [ABSTRACT FROM AUTHOR]

Background IL-6 is a proinflammatory cytokine reported to play an important role in the induction of cerebral vasospasm after subarachnoid hemorrhage (SAH). Suppressor of cytokine signaling 3 (SOCS3) is known to act as an inhibitor of signal transduction of IL-6. However, there have been no reports on the expression of SOCS3 in cerebrospinal fluid (CSF) after SAH. Findings The concentration of IL-6 was measured serially up until day 10, in CSF of eight patients with SAH. CSF samples obtained from patients suffering from an unruptured aneurysm were used as controls. The expression of SOCS3 in CSF was further examined by immunoprecipitation methods. Concentrations of IL-6 in CSF increased immediately after the onset of SAH and remained chronically elevated over control values. SOCS3 was significantly expressed in CSF on days 1 to 3 after SAH. Conclusions Our findings suggest that SOCS3 regulates IL-6 signaling as an antagonist in CSF, immediately following SAH. As the expression of SOCS3 decreases after day 5, IL-6 signals might then be more easily transmitted, presumably resulting in cerebral vasospasm. [ABSTRACT FROM AUTHOR]

Study Design. Observational study using a retrospective single- institute database. Objective. To investigate the variance of the vertebral artery (VA) V2 segment and the anatomical features of the C7 pedicle with or without VA entry based on computed tomographic (CT) angiography in 919 consecutive Japanese subjects. Summary of Background Data. Generally, the level of the VA entrance into the transverse foramen is assumed to be C6. Therefore, surgeons tend to pay less attention to VA injury when inserting a C7 pedicle screw. However, anomalies at C7 surely exist and are considered to be 1 of the major risk factors for VA injury during posterior instrumentation. Methods. Subjects who underwent contrast-enhanced CT or CT angiography from November 2011 to October 2012 were eligible. The entrance into the transverse foramen was reviewed. In addition, anatomical features of C7 with or without VA entrance were measured. Results. A total of 919 subjects with a mean age of 56.1 years were surveyed. From among 1838 VA courses, VA entered the C6 transverse foramen in 95.6% of specimens (1757 of 1838 VA courses). Sixty-seven of 919 subjects (7.3%) had a unilateral anomaly and 7 (0.8%) had a bilateral anomaly. An abnormal level of entrance was observed in 8.1% of subjects (74 of 919 patients), and 4.4% of specimens (81 of 1838 VA courses), with a level of entrance into the C4, C5, or C7 transverse foramen in 0.5% (n = 10), 3.1% (n = 57), and 0.8% (n = 14) of all specimens, respectively. C7 transverse foramen with a VA entrance was wider in those without a VA entrance, and abnormal cases frequently showed an uneven transverse foramen. Therefore, the C7 pedicle diameter with abnormal VA entrance was significantly narrower in those without VA entrance (P < 0.01 ; t test), Conclusion. CT angiography is recommended in cases with an uneven transverse foramen for confirming vascular anomaly. [ABSTRACT FROM AUTHOR]