Vapor-Transport Synthesis and Annealing Study of Zn x Mg1-x O Nanowire Arrays for Selective, Solar-Blind UV-C Detection.

This work uniquely reports the synthesis of Zn x Mg1-x O nanowires and submicron columns by utilizing a traditional carbothermal reduction process toward forming ZnO nanowire ultraviolet detectors, while simultaneously utilizing Mg3N2 as the source of Mg. To investigate the relationship between Mg content in the ZnO lattice and the cutoff wavelength for high spectral responsivity, the nanowires were annealed in a series of designed conditions, whereas chemical, nanostructural, and optoelectronic characteristics were compared before and after treatment. Postanneal scanning electron micrographs revealed a reduction of the average ensemble nanowire dimensions, which was correlated to the modification of ZnO lattice parameters stemming from Zn2+ dissociation and Mg2+ substitution (confirmed via Raman spectroscopy). The analysis of cathodoluminescence spectra revealed a blueshift of the peak alloy band-edge emission along with a redshift of the ZnO band-edge emission; and both were found to be strong functions of the annealing temperature. The conversion of Zn2SiO4 to Mg2SiO4 (in O2) and MgSiO3 (in Ar) was found to correspond to transformations (shifting and scaling) of high-energy luminescence peaks and was confirmed with X-ray diffraction analysis. The tunability of the cutoff photodetection wavelength was evaluated as the nanowire arrays exhibited selective absorption by retaining elevated conduction under high-energy UV-C irradiation after thermal treatment but exhibiting suppressed conductivity and a single order of magnitude reduction in both spectral responsivity (R λ) and photoconductive gain (G) under UV-A illumination. Noise analysis revealed that the variation of detectivity (D*) depended on the regime of ultraviolet irradiation, and that these variations are related to thermal noise resulting from oxygen-related defects on both nanowire and substrate surfaces. These results suggest a minor design tradeoff between the noise characteristics of thermally treated ZnMgO nanowire array UV detectors and the tunability of their spectral sensitivity.

Enhancement of motor coordination by applying high frequency repetitive TMS on the sensory cortex.

The sensory function plays an important role for successful motor performance. We investigated the modulating effects of high frequency repetitive transcranial magnetic stimulation (rTMS) on sensory discrimination and motor coordination. Twenty healthy participants were assigned into two random groups; the real- and sham-rTMS group. Total of 900 rTMS pulses at a frequency of 10Hz (stimulus intensity of 90% RMT) were given over deltoid representational areas of the somatosensory cortex. Sensory discrimination ability was evaluated using two-point discrimination test. Motor coordination was measured by the latency difference between the synchronized contraction of deltoid and abductor pollicis brevis muscles before and after rTMS. The sensory discrimination was significantly increased only in the deltoid area and the difference in the latency of synchronized contraction of two muscles was significantly shortened after real-rTMS compared sham condition, which had tendency of negative correlation following real-rTMS condition. The results of this study demonstrated rTMS-induced enhancement of sensorimotor integration, which may contribute to develop effective therapeutic strategies for rehabilitation of various sensorimotor disorders in the clinical setting.

Measurement of synergy and spasticity during functional movement of the post-stoke hemiplegic upper limb.

The aim of the present study was to measure the muscle-contraction patterns of the hemiplegic upper limb using electromyography (EMG) and to investigate the relationship between muscle co-contraction and functional recovery in stroke patients presenting with synergy and spasticity. The muscle-contraction patterns of the upper limb of 12 chronic stroke patients and 10 normal volunteers were measured, and the co-contraction in the distal and proximal muscles was simultaneously quantified, while the participants performed hand-grasp and shoulder flexion tasks. The spasticity and hemiplegic arm function were evaluated, respectively, on a modified Ashworth scale (MAS) and by means of Fugl-Meyer motor assessment (FMA). The correlation between the MAS and FMA values was analyzed. Increased co-contraction (66-555%) was observed in both the proximal and distal upper limbs, and was positively correlated with spasticity of the elbow flexor (r = 0.944 on shoulder flexion, r = 0.741 on hand grasping, p < 0.01) and negatively correlated with functional recovery of the upper limb (r = -0.670 ∼ -0.884, p < 0.05). Specific movement patterns influenced by synergy and spasticity were confirmed by EMG. These results might prove useful to the formulation of appropriate management plans such as those involving botulinum toxin injection or nerve block.

Dementia due to Meningovascular Syphilis in Medial Temporal Lobe and Cognitive Rehabilitation.

The temporal lobe is essential in saving declarative memory and plays an important role along with the cerebral neocortex in creating and maintaining long-term memory. Damage to the temporal lobe is expected to result in cognitive impairment or dementia, which has characteristic symptoms such as cognitive and behavioral dysfunction and decreasing self-reliance in activities of daily living. We report on a patient, who suffered from dementia due to meningovascular syphilis affecting the medial temporal lobe, and on the outcome of cognitive rehabilitation.

Efficacy comparison of ramosetron with ondansetron on preventing nausea and vomiting in high-risk patients following spine surgery with a single bolus of dexamethasone as an adjunct.

BACKGROUND: Despite the development of a new class of antiemetics, postoperative nausea and vomiting (PONV) still remains a frequent and distressing complication. We compared the prophylactic antiemetic effect of administering dexamethasone 5 mg as an adjunct to ramosetron and ondansetron in patients at high-risk for PONV following lumbar spinal surgery. METHODS: In this randomized, double-blind study, 120 female non-smoking patients with intravenous patient-controlled analgesia (PCA) received ramosetron 0.3 mg plus dexamethasone 5 mg (group R + D) or ondansetron 4 mg plus dexamethasone 5 mg (group O + D) intravenously. Fentanyl-based PCA was administered for 48 hr postoperatively; ramosetron 0.3 mg or ondansetron 12 mg was added to the PCA regimen according to the allocated group. The incidence of PONV and rescue antiemetic were assessed for 48 hr postoperatively at 0-6, 6-24, and 24-48 hr. RESULTS: The overall incidence of PONV did not differ between the groups (50% vs. 60%, in groups R + D and O + D, respectively). The overall incidence of nausea was similar between groups (47% vs. 60%, in groups R + D and O + D, respectively). The overall frequency of vomiting was also similar between groups (8% vs. 12%, in groups R + D and O + D, respectively). The severity of nausea and the overall use of rescue antiemetic were not different between groups. CONCLUSIONS: The antiemetic efficacy of ramosetron plus dexamethasone was similar to that of ondansetron plus dexamethasone on preventing PONV in high-risk patients undergoing lumbar spinal surgery.