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Touch is a crucial sense for perceiving the spatial characteristics of objects. The JVP dome was developed to evaluate tactile spatial acuity using a grating orientation task. The application of the traditional JVP dome to assess tactile function was limited by the ceiling effect, excessive transition gap between grating widths causing inaccurate tactile discrimination threshold measurement, and predictive bias due to the common execution protocol using grating widths in sequence. In this study, we included additional grating domes and proposed a modified examining protocol for estimating tactile discrimination thresholds to improve the accuracy of tactile function assessment. Twelve healthy participants were enrolled in this experiment. Extended JVP domes with 11 different groove widths were designed. Tactile discrimination thresholds were estimated using a modified two-down-one-up staircase method. The experiment comprised practice, training, and testing sessions, conducted by trained examiners who performed grating stimulation on participants index fingerpads. All participants passed the required accuracy in the practice and training sessions. Eight transition points were obtained in the testing session for each participant, and tactile discrimination thresholds were all within the width range of the extended JVP domes. The mean tactile discrimination threshold was 2.09 ± 0.84 mm. The results demonstrated that the proposed modified JVP dome set and protocol were successfully applied to assess tactile discrimination thresholds. The modified protocol with extended JVP domes provided an effective assessment of tactile function and improved the precision of threshold measurements, avoided the ceiling effect found in traditional JVP dome, and eliminated predictive bias.

The hand explores the environment for obtaining tactile information that can be fruitfully integrated with other functions, such as vision, audition, and movement. In theory, somatosensory signals gathered by the hand are accurately mapped in the world-centered (allocentric) reference frame such that the multi-modal information signals, whether visual-tactile or motor-tactile, are perfectly aligned. However, an accumulating body of evidence indicates that the perceived tactile orientation or direction is inaccurate; yielding a surprisingly large perceptual bias. To investigate such perceptual bias, this study presented tactile motion stimuli to healthy adult participants in a variety of finger and head postures, and requested the participants to report the perceived direction of motion mapped on a video screen placed on the frontoparallel plane in front of the eyes. Experimental results showed that the perceptual bias could be divided into systematic and nonsystematic biases. Systematic bias, defined as the mean difference between the perceived and veridical directions, correlated linearly with the relative posture between the finger and the head. By contrast, nonsystematic bias, defined as minor difference in bias for different stimulus directions, was highly individualized, phase-locked to stimulus orientation presented on the skin. Overall, the present findings on systematic bias indicate that the transformation bias among the reference frames is dominated by the finger-to-head posture. Moreover, the highly individualized nature of nonsystematic bias reflects how information is obtained by the orientation-selective units in the S1 cortex.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The chemical stability of potassium substituted for A-site of SrCe 0.95 Y 0.05 O 3 specimens was examined under CO 2 atmosphere treated at 600 °C and further analyzed by X-ray diffractometer to see their CO 2 -resisted capabilities. According to thermodynamic data, the Gibbs free energy of CeO 2 was lower than that of SrCO 3 at the temperature of 600 °C. Thus the formation of CeO 2 might be faster than that of SrCO 3 in SrCeO 3− based materials under CO 2 atmosphere. Unfortunately, the chemical stability of SrCe 0.95 Y 0.05 O 3 materials in CO 2 atmosphere was reduced with increasing potassium-substituted amount. The microstructures of Sr 1− x K x Ce 0.95 Y 0.05 O 3 sintered specimens were identified using field emission scanning electron microscope. The conductivity in moisture H 2 atmosphere (RH 30%) was increased with increasing potassium-substituted concentration. The conductivity reached a maximum of 0.0081 Scm -1 at 900 °C for Sr 0.95 K 0.05 Ce 0.95 Y 0.05 O 3 sintered specimens in moisture H 2 atmosphere (RH 30%). Potassium substituted for A-site of SrCe 0.95 Y 0.05 O 3 could improve the conductivity but not CO 2 -resisted capability.

A Fe–Cr alloy, used for metallic interconnects, was coated with a protective layer of lanthanum strontium manganite (LSMO) using the aerosol deposition method (AD). The effects of the LSMO protective layer, which was coated on the Fe–Cr interconnects using AD, on the area specific resistance (ASR) during high temperature oxidation and the Cr evaporation behaviors were systematically investigated in this paper. The microstructures, morphologies, and compositions of the oxidized scales that appeared on the LSMO-coated Fe–Cr alloy after annealing at 800 °C for 750 h in air were examined using SEM equipped with EDS. The EPMA mapping of the LSMO-coated Fe–Cr interconnects undergoing long term, high-temperature oxidation was used to explain the formation layers of the oxidized scale, which consists of (Mn,Cr) 3 O 4 and Cr 2 O 3 layers. Moreover, the experimental results revealed that the AD process is a potential method for preparing denser protective layers with highly desirable electrical properties for metallic interconnects.

Five selected alloys, Crofer22 APU, Crofer H, ss441 and two different ZMG232 were selected for a cautious study. Our major focus is on the materials' resistance to oxidation and Cr evaporation. Both issues remain to be major concerns in many applications, particularly for interconnects in solid oxide fuel cells. For the part of oxidation, samples of five alloys are placed in an oven heating at 800 °C for 250 h. The microstructures, morphologies and compositions of samples after oxidation are analyzed by SEM, XRD, EDS on surfaces and cross-sections. Electrical resistance of samples during oxidation is measured by four-point probe to obtain their variations over time. An assembly, of which two alumina plates sandwiching the samples alloys, is specifically designed to test the resistance of specimens to Cr evaporation, which is gauged by the amount of deposited Cr on the two alumina plates under long-hour oxidation. Experimental results revealed that Crofer22 APU has a better performance than others after long-hour oxidation with thinner oxidized layer, lower electrical resistance and less Cr evaporation.

Neuronal oscillations have been shown to contribute to the function of the cerebral cortex by coordinating the neuronal activities of distant cortical regions via a temporal synchronization of neuronal discharge patterns. This can occur regardless whether these regions are linked by cortico-cortical pathways or not. Less is known concerning the role of neuronal oscillations in the cerebellum. Golgi cells and Purkinje cells are both principal cell types in the cerebellum. Purkinje cells are the sole output cells of the cerebellar cortex while Golgi cells contribute to information processing at the input stage of the cerebellar cortex. Both cell types have large cell bodies, as well as dendritic structures, that can generate large currents. The discharge patterns of both these cell types also exhibit oscillations. In view of the massive afferent information conveyed by the mossy fiber-granule cell system to different and distant areas of the cerebellar cortex, it is relevant to inquire the role of cerebellar neuronal oscillations in information processing. In this study, we compared the discharge patterns of Golgi cells and Purkinje cells in conscious rats and in rats anesthetized with urethane. We assessed neuronal oscillations by analyzing the regularity in the timing of individual spikes within a spike train by using autocorrelograms and fast-Fourier transform. We measured the differences in neuronal oscillations and the amount of information content in a spike train (defined by Shannon entropy processed per unit time) in rats under anesthesia and in conscious, awake rats. Our findings indicated that anesthesia caused more prominent neuronal oscillations in both Golgi cells and Purkinje cells accompanied by decreases in Shannon information entropy in their spike trains.

Al-Si alloys, with such excellent properties as low weight, low thermal expansion coefficient, and high wear-resistance, are ideal materials for the automobile and aerospace industries. However, their applications have been hampered by the coarsening of the primary-Si particles in Al-Si alloys. In this study, simple plastic deformation was used to reduce primary-Si particles and to improve the wear-resistance and mechanical strength of Al-Si alloys. Experimental results showed that mechanical rolling decreased the grain size of primary-Si particles in Al-Si alloys and reduced the variation in silicon particle size. After 60%-roll-reduction, the alloy showed an improved tensile strength of 340 MPa, which is attributed to the work hardening of the aluminum matrix and the dispersion strengthening of the primary-Si particles. Data from wear-resistance testing showed that rolling led to a reduction in wear loss. This improvement in wear resistance is due to the particle size refinement of silicon at a high percentage-roll-reduction.

A ~1.2 meter long trough comprising of variable cross-sections, with the highest ratio of depth to opening width reaching 1.4, is gas-formed at 500°C with superplastic aluminum alloy 5083. It is a challenge to successfully make such an industrial scale part as demonstrated in this paper. Starting as an expanded V-shaped groove, pressurized gas is manipulated to flow into the forming die, and the pressure vs. time profile needs to be calculated. Thus, the flow stress in the deforming material is optimal to maintain desired strain rate correspondingly. Thickness distribution over the formed product is far from uniform. The other even undesired result is that the thinnest region suffers severe cavitation

This research studies a brand new Magnesium Lithium Alloy, LAZ1151, with trace Sc additions. The mechanical properties and microstructures of the as-cast and alloys after three and six month aging were observed and analyzed. Microstructure and XRD confirms the existence of α phase precipitates (Mg rich) in both as-cast and aging specimens of the alloy. Grain growth was observed in the alloy after room temperature aging. The tensile strength of the as-cast LAZ1151 is 147 MPa; the value is decreased to 135 MPa after six month aging, showing typical room temperature softening. Strengthening via the use of cold rolling was tried; a maximum tensile strength of 180 MPa was achieved after 90% rolling reduction, which is mainly due to strain hardening.

The transformation characterization of Ni(OH)2/NiOOH in Ni-Pt films was investigated using an electrochemical quartz crystal microbalance (EQCM) in an alkaline electrolyte under various experiment conditions. The Ni-Pt films were prepared by electro-deposition on gold-coated quartz crystal chips. When cyclic voltammetry (CV) was performed continually, the OHions diffused into the Ni-Pt film to form Ni(OH)2. The transformation from mixed type Ni(OH)2/NiOOH to � -Ni(OH)2/� -NiOOH occurred gradually. The phase transformation of Ni(OH)2/NiOOH was strongly affected by the composition, deposited weight, and aging conditions of the Ni-Pt films. The results show that high Pt content or high deposited weight of Ni-Pt films postponed the transformation to the � -Ni(OH)2/� -NiOOH phase. � -Ni(OH)2 was directly formed by dipping fresh Ni-Pt films in KOH solution while mixed type Ni(OH)2 was obtained after aging fresh Ni-Pt films in humid O2 atmosphere. These two pre-aging conditions accelerate the phase transformation of Ni(OH)2/NiOOH into � -Ni(OH)2/� -NiOOH. After 1050 and 2100 cycles of the electro-oxidation process of ethanol, the Ni(OH)2 phase in Ni-Pt films still remained in a � -Ni(OH)2-like phase with some � -Ni(OH)2. The well-defined � -Ni(OH)2 phase that formed in the Ni-Pt film after 1050 cycles of CV was more stable in a KOH solution than in a humid O2 atmosphere at room temperature. Ni-Pt films were also evaluated as a sensing element for an ethanol sensor. (doi:10.2320/matertrans.M2010079)

An amperometric sensor for monitoring ethanol concentration using a Ni–Pt alloy electrode has been developed. The films of Ni–Pt alloy were electrodeposited under various potentials on an Au/Al2O3 substrate. To examine the effects of Ni–Pt alloy films on the sensing performance, the electrodes with various Ni:Pt atomic proportions of 100:0, 25:75, 70:30, 82:18 and 0:100 were prepared and tested. X-ray diffraction and scanning electron microscope analyses indicate that Ni atoms of Ni–Pt alloy electrodes are inserted in the Pt lattice and a pyramid-like structure is formed with an increase of Pt content in the film. All the prepared electrodes have a linear relationship between response current and ethanol concentration for the detection range of 50 to 300 ppm ethanol in alkaline solutions. With an increase of Pt content in the film, the response time of the Ni–Pt alloy electrodes was reduced whereas the sensitivity was decreased. The sensor with 70 at.% Pt in the film was most stable with the duration over a 63-day-period. The sensitivity of the Ni–Pt alloy electrodes for detecting glucose, various alcohols and acids have also been studied.

Oscillations are fundamental to communication between neuronal ensembles. We previously reported that pain in awake rats enhances synchrony in primary somatosensory cortex (S1) and attenuates coherence between S1 and ventral posterolateral (VPL) thalamus. Here, we asked whether similar changes occur in anesthetized rats and whether pain modulates phase-amplitude coupling between VPL and S1. We also hypothesized that the suppression of burst firing in VPL using Z944, a novel T-type calcium channel blocker, restores S1 synchrony and thalamocortical connectivity. Local field potentials were recorded from S1 and VPL in anesthetized rats 7 days after sciatic chronic constriction injury (CCI). In rats with CCI, low-frequency (4-12 Hz) synchrony in S1 was enhanced, whereas VPL-S1 coherence and theta-gamma phase-amplitude coupling were attenuated. Moreover, Granger causality showed decreased informational flow from VPL to S1. Systemic or intrathalamic delivery of Z944 to rats with CCI normalized these changes. Systemic Z944 also reversed thermal hyperalgesia and conditioned place preference. These data suggest that pain-induced cortical synchrony and thalamocortical disconnectivity are directly related to burst firing in VPL.

Neural responses to sensory inputs caused by self-generated movements (reafference) and external passive stimulation (exafference) differ in various brain regions. The ability to differentiate such sensory information can lead to movement execution with better accuracy. However, how sensory responses are adjusted in regard to this distinguishability during motor learning is still poorly understood. The cerebellum has been hypothesized to analyze the functional significance of sensory information during motor learning, and is thought to be a key region of reafference computation in the vestibular system. In this study, we investigated Purkinje cell (PC) spike trains as cerebellar cortical output when rats learned to balance on a suspended dowel. Rats progressively reduced the amplitude of body swing and made fewer foot slips during a 5-min balancing task. Both PC simple (SSs; 17 of 26) and complex spikes (CSs; 7 of 12) were found to code initially on the angle of the heads with respect to a fixed reference. Using periods with comparable degrees of movement, we found that such SS coding of information in most PCs (10 of 17) decreased rapidly during balance learning. In response to unexpected perturbations and under anesthesia, SS coding capability of these PCs recovered. By plotting SS and CS firing frequencies over 15-s time windows in double-logarithmic plots, a negative correlation between SS and CS was found in awake, but not anesthetized, rats. PCs with prominent SS coding attenuation during motor learning showed weaker SS-CS correlation. Hence, we demonstrate that neural plasticity for filtering out sensory reafference from active motion occurs in the cerebellar cortex in rats during balance learning. SS-CS interaction may contribute to this rapid plasticity as a form of receptive field plasticity in the cerebellar cortex between two receptive maps of sensory inputs from the external world and of efference copies from the will center for volitional movements.

Granger causality (GC) analysis has emerged as a powerful analytical method for estimating the causal relationship among various types of neural activity data. However, two problems remain not very clear and further researches are needed: (1) The GC measure is designed to be nonnegative in its original form, lacking of the trait for differentiating the effects of excitations and inhibitions between neurons. (2) How is the estimated causality related to the underlying synaptic weights? Based on the GC, we propose a computational algorithm under a best linear predictor assumption for analyzing neuronal networks by estimating the synaptic weights among them. Under this assumption, the GC analysis can be extended to measure both excitatory and inhibitory effects between neurons. The method was examined by three sorts of simulated networks: those with linear, almost linear, and nonlinear network structures. The method was also illustrated to analyze real spike train data from the anterior cingulate cortex (ACC) and the striatum (STR). The results showed, under the quinpirole administration, the significant existence of excitatory effects inside the ACC, excitatory effects from the ACC to the STR, and inhibitory effects inside the STR.

Axon collateral projections to various lobules of the cerebellar cortex are thought to contribute to the coordination of neuronal activities among different parts of the cerebellum. Even though lobules I/II and IX/X of the cerebellar vermis are located at the opposite poles in the anterior-posterior axis, they have been shown to receive dense vestibular mossy fiber projections. For climbing fibers, there is also a mirror-image-like organisation in their axonal collaterals between the anterior and posterior cerebellar cortex. However, the detailed organisation of mossy and climbing fiber collateral afferents to lobules I/II and IX/X is still unclear. Here, we carried out a double-labeling study with two retrograde tracers (FluoroGold and MicroRuby) in lobules I/II and IX/X. We examined labeled cells in the vestibular nuclei and inferior olive. We found a low percentage of double-labeled neurons in the vestibular nuclei (2.1 ± 0.9% of tracer-labeled neurons in this brain region), and a higher percentage of double-labeled neurons in the inferior olive (6.5 ± 1.9%), especially in its four small nuclei (18.5 ± 8.0%; including the β nucleus, dorsal cap of Kooy, ventrolateral outgrowth, and dorsomedial cell column), which are relevant for vestibular function. These results provide strong anatomical evidence for coordinated information processing in lobules I/II and IX/X for vestibular control.

Thin films of RuO2 were prepared by reactive rf sputtering from a Ru target in an Ar+O2 atmosphere, with the oxygen concentration varying from 10% to 100%. The resistivity, deposition rate, crystal structure, surface morphology, composition and chemical binding state of RuO2 films were investigated. RuO2 films sputtered with 33% or more oxygen exhibited lower deposition rate and lower resistivity relative to the films sputtered with 10 or 20% oxygen. The O/Ru ratios of the RuO2 films sputtered with 10, 20 and 50% oxygen were similar; however, evident rutile structure was only observed for films sputtered with 50% O2. The low resistivity is related with the crystallinity of the films. The RuO2 films sputtered with 50% oxygen were annealed in flowing oxygen at 200–750°C for 30 min. The film resistivity was further decreased with increasing annealing temperature and reached a minimum value of 110 μΩ cm after annealing at 650°C. From X-ray diffraction and scanning electron microscopy analyses, the decrease of film resistivity upon annealing is attributed to the grain growth and reduction of lattice spacing in the RuO2 films.

Efficient nanotextured black silicon solar cells passivated by an Al2O3 layer are demonstrated. The broadband antireflection of the nanotextured black silicon solar cells was provided by fabricating vertically aligned silicon nanowire (SiNW) arrays on the n(+) emitter. A highly conformal Al2O3 layer was deposited upon the SiNW arrays by the thermal atomic layer deposition (ALD) based on the multiple pulses scheme. The nanotextured black silicon wafer covered with the Al2O3 layer exhibited a low total reflectance of ∼1.5% in a broad spectrum from 400 to 800 nm. The Al2O3 passivation layer also contributes to the suppressed surface recombination, which was explored in terms of the chemical and field-effect passivation effects. An 8% increment of short-circuit current density and 10.3% enhancement of efficiency were achieved due to the ALD Al2O3 surface passivation and forming gas annealing. A high efficiency up to 18.2% was realized in the ALD Al2O3-passivated nanotextured black silicon solar cells.

Four metallic alloys, namely 2205 duplex stainless steel (2205DSS), ZMG232, and stainless steels SS430 and SS304 are investigated for use as interconnects in solid oxide fuel cells (SOFCs). A La0.67Sr0.33MnO3–δ (LSMO) film is deposited on these metallic-alloy substrates using a pulsed-DC magnetron sputtering system in the reactive mode, leading to the formation of a cubic perovskite structure. The coated alloys are then subjected to oxidizing heat treatments in air at 600 °C, 700 °C, 800 °C, and 900 °C, and their microstructures as well as electrical resistances are evaluated. The electrical resistance measurements are performed at 800 °C, and the area-specific resistance (ASR) of the film-coated 2205DSS alloy is found to be less than that of the uncoated alloy. This is because a thick layer of Cr2O3 and a (Mn, Fe)Cr2O4 spinel phase layer are formed, and some divalent metallic ions migrate into the Cr2O3 layer. It is found that alloys coated with a thin film of LSMO are more suitable for use as metallic interconnects in SOFCs with intermediate-temperature operating ranges.

The influence of acute D2 agonist quinpirole on locomotor activity has been effectively characterized. However, few studies have addressed the dynamic changes in neuronal activity of the anterior cingulate cortex (ACC) and striatum (STR), two crucial regions for cognitive and motor functions, after quinpirole administration. This study was conducted in order to acquire detailed information on the evoked activity of the neurons in the ACC and STR after acute quinpirole administration. Multichannel electrophysiological recording was used for tracking neuronal activity in the ACC and STR of urethane-anesthetized rats after administration of saline or 0.05 or 0.5 mg/kg quinpirole. In contrast to the responses to saline, quinpirole dose-dependently increased the ratio of neurons, the activity of which was inhibited in the ACC and STR. By examining the ensemble neuronal activities of inhibition-responded neurons, there was no significant activity difference among the “treatments” (saline and low- and high-dose quinpirole), the “periods” (the duration of 0–15 and 16–45 min after i.v. injection), and the interaction between “treatments” and “periods.” Regarding activation-responded neurons, however, there was a significant “periods” difference in both ACC and STR, and the activity of 16–45 min was significantly higher than the activity of 0–15 min after high-dose quinpirole administration in ACC (p

Background Alcohol is a widely abused substance and is responsible for significant morbidity and mortality worldwide. The precise mechanisms underlying ethanol (EtOH)'s actions in the central nervous system (CNS) remain elusive. In vitro studies suggest that GABAergic interneurons are important targets of EtOH action in the CNS. Although EtOH generally acts to inhibit CNS neurons, it appears to cause an increase in GABAergic interneuron excitability. However, it has yet to be demonstrated that EtOH produces this effect in the brain of behaving animals. Here, we demonstrate for the first time that acute EtOH exposure excites a subtype of GABAergic interneuron (cerebellar Golgi cell [GoC]) in a freely moving animal. Methods Electrophysiological recordings were made from microwire arrays implanted in the anterior cerebellum of freely moving rats. Results Cerebellar GoCs display a slow, irregular, spontaneous action potential firing pattern under control conditions. EtOH caused dramatic and consistent increases in the rate and regularity of GoC discharges, including a redistribution of the power in the GoC spike train, such that power became concentrated in the 26.7 ± 7.3 Hz region. Conclusions Taken together with our previous findings, these data suggest that a major mechanism of EtOH actions on cerebellar function is an EtOH-induced de-afferentation at the input stage of the cerebellar cortex in the form of granule cell inhibition, and that this inhibition is caused by an increase in GoC firing. It is likely that GoCs may play a significant role both in the gating of information transmission to granule cells and in the modulation of the overall excitability of the cerebellum by tonically controlling granule cell activity.

We constructed a chassis that tightly fixes catheters for cannulation to the muscle. It can buffer pulling forces to avoid a mechanical tearing of the skin of mice as a result of movement. A simple hydraulic swivel was also made for blood pressure recording and drug infusion in freely moving mice.

The aim of this study was to propose an electrocardiogram (ECG) de-noising framework based on ensemble empirical mode decomposition (EEMD) to eliminate electromyography (EMG) interference without signal distortion. ECG signals are easily corrupted by EMG, especially in Holter monitor recordings. The frequency component overlapping between EMG and ECG is a challenge in signal processing that remains to be solved. The aim of the present study, therefore, was to resolve ECG signals from recorded segments with EMG noise. Two units were put into our proposed framework; first, modified moving average filter for signal preprocessing to cancel baseline wandering, and second, EEMD to cancel EMG. In order to enhance the de-noising capability (such as signal distortion in traditional EEMD), we developed a novel EEMD signal reconstruction algorithm using a statistical ECG model. We tested the proposed framework using MIT-BIH database, artificial and single-lead recorded real-world noisy signals. Correlation coefficients and ECG morphological features were used to evaluate the performance of the proposed algorithm. Our results showed that the proposed de-noising algorithm successfully resolved ECG signals from baseline wandering and EMG interference without distorting the signal waveform.

Corrigendum to “Determination of alcohols using a Ni–Pt alloy amperometric sensor” [Thin Solid Films 516 (2008) 5210–5216] Jian-Jia Huang , Weng-Sing Hwang ⁎, Yu-Ching Weng , Tse-Chuan Chou b,c a Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan b Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan c Department of Chemical Engineering, Tatung University, Taipei, Taiwan

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