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A series of unsynthesized perovskite-type oxyhydrides ATiO2H (A = Li, Na, K, Rb, Cs) are investigated by the density functional calculations. These oxyhydrides are stable in the sense of the formation energies for some possible synthesis reactions. They are crystallized into quite similar crystal structures with the long c-axis, and the corner-sharing TiO4H2 octahedra of the ideal perovskite-type structure are deformed into the 5-fold coordinated titanium atoms with the OH plane and the apical oxygen atoms. All of these oxyhydrides exhibit two-dimensional electronic states at the valence band maximum characterized by the in-plane oxygen 2p and the hydrogen 1s orbitals. While the c-axis becomes short as the ionic radius of the A atom becomes small and the two-dimensional characteristics are weakened, the electronic state at the valence band maximum is still characterized as the O-H in-plane state. Additionally, the Born effective charge tensors, spontaneous electric polarizations, dielectric tensors, and piezoelectric tensors are evaluated. It is found that the spontaneous electric polarizations of these oxyhydrides are much larger than that of tetragonal BaTiO3.

Helping behavior is a prosocial behavior whereby an individual helps another irrespective of disadvantages to him or herself. In the present study, we examined whether rats would help distressed, conspecific rats that had been soaked with water. In Experiment 1, rats quickly learned to liberate a soaked cagemate from the water area by opening the door to allow the trapped rat into a safe area. Additional tests showed that the presentation of a distressed cagemate was necessary to induce rapid door-opening behavior. In addition, it was shown that rats dislike soaking and that rats that had previously experienced a soaking were quicker to learn how to help a cagemate than those that had never been soaked. In Experiment 2, the results indicated that rats did not open the door to a cagemate that was not distressed. In Experiment 3, we tested behavior when rats were forced to choose between opening the door to help a distressed cagemate and opening a different door to obtain a food reward. Irrespective of how they learned to open the door, in most test trials, rats chose to help the cagemate before obtaining a food reward, suggesting that the relative value of helping others is greater than the value of a food reward. These results suggest that rats can behave prosocially and that helper rats may be motivated by empathy-like feelings toward their distressed cagemate.

In order to investigate the effects of ageing on face perception, we studied the magnetic responses to face images in 15 young (19-38 years) and 10 elderly (51-81 years) subjects. Face-specific responses (160mF), which originate in the inferior occipitotemporal cortices, and face non-specific responses (100m), which originate in the primary visual cortices, were evoked in all subjects. Averaged peak latency of the 160mF in the elderly group (174.0+/-9.1 ms) was significantly longer (P0.0005) than that in the young group (161.5+/-5.1 ms), while no inter-group difference was found in the 100m latency. There was a significant correlation between age and 160mF latency (+0.35 ms/year, R=0.747) suggesting age-related decline of face perception.

To examine the ability of monkeys to detect the direction of attention of other individuals, the authors quantitatively investigated the visual scanning pattern of rhesus monkeys (Macaca mulatta) in response to visually presented images of a human frontal face. The present results demonstrated not only that monkeys predominantly gaze at the eyes as compared with other facial areas in terms of duration and number of fixations, but also that they gaze at the eyes for a longer time period and more frequently when a human face, presented as a stimulus, gazed at them than when the gaze was shifted. These results indicate that rhesus monkeys are sensitive to the directed gaze of humans, suggesting that monkeys pay more attention to the human whose attention is directed to them.

In this article, I discuss the process of navigation through reviewing the function of the primate parahippocampal cortex based on recent studies in humans and monkeys. Studies of brain damaged patients and of functional brain imaging suggest that the human parahippocampal cortex is involved in the scene recognition process. The parahippocampal cortex widely connects with other brain areas, including areas in the dorsal pathway as well as those in the ventral pathway. Monkeys damaged with the parahippocampal cortex are impaired on complex spatial memory tasks but on object recognition tasks. Neurons in the parahippocampal cortex respond to visual stimuli, and a few neuronal studies suggest the spatial function of the parahippocampal cortex. These studies suggest that the parahippocampal cortex is involved in the visuo-spatial processing. Further studies as to the role of the parahippocampal cortex will elucidate the scene recognition and navigation processes.

Using magnetoencephalography (MEG), the neural response to scenes was recorded and compared with that to faces. The prominent MEG signals in response to scenes appeared 200-300 ms after the stimulus presentation while those in response to faces appeared between 150 and 200 ms. Source locations of the signals were estimated in the right parahippocampal and parieto-occipital regions with a latency of 300 ms for the scene response, whereas those were estimated in the lingual or fusiform gyri bilaterally with a latency of 160 ms for the face response. These data suggest that both the temporal and parietal regions process scenes, while the occipito-temporal regions process faces, and that scene processing takes a longer time than face processing.

Electroencephalograms (EEGs) were recorded from the rat hippocampal CA1, dentate gyms, entorhinal cortex, and cingulate cortex during the performance of a delayed nonmatching-to-sample task. The recording of EEGs was divided into four task phases—control, sample, delay, and comparison—so that the relationship between the EEG and specific task events could be investigated. The amplitude of theta activity (6–8 Hz) in the hippocampal CA1 increased during the comparison phase and increased differentially when rats made correct go response in the nonmatching trials. Between the hippocampal CA1 and the entorhinal cortex, and the CA1 and the cingulate cortex, EEG synchronization was higher in three task-related phases (sample, delay, and comparison) than in the control phase. These results suggest that hippocampal theta activity is involved in a mnemonic process of comparison between retained and current stimuli and that synchronized activity between the hippocampus and the related cortical structures was also involved in such a mnemonic process.

Accurate in-situ molecular beam epitaxial growth of vertical cavity surface emitting lasers on a rotating GaAs wafer is demonstrated using inclined incident He–Ne laser reflectometry. A sinusoidal intensity variation signal is observed in the reflected light when it is monitored at a fixed position on a rotating wafer. This modulated signal is found important to give the information about the growth rate from as short as half a period of these oscillations. High precision in measurement is confirmed with reproducibility of the thickness results and its control for high accuracy is proposed.

When we have a non-degenerate commuting square of finite dimensional C∗-algebras, we can construct a subfactor in two ways. One is by a repetition of basic constructions in a horizontal direction and the other in a vertical direction. We prove that if one of the two is of finite depth, so is the other. Furthermore, we prove the two have the same global indices in the sense of A. Ocneanu. This gives an answer to a question V.F.R. Jones raised in his talk at Aarhus in June, 1995. We actually prove a more general result on flatness and also give an example of a new finite principal graph as its application.

We prove that the flatness condition in Ocneanu's paragroup theory for graphs with depth two is equivalent to existence of the multiplicative unitaries in the theory of Baaj-Skandalis by using "Fourier transform" introduced by A. Ocneanu. Moreover, from two Kac algebras dual to each other, we construct a subfactor as a crossed product by a Kac algebra action, with the string algebra construction.

We presented optic flow simulating eight directions of self-movement in the ground plane, while monkeys performed delayed match-to-sample tasks, and we recorded dorsal medial superior temporal (MSTd) neuronal activity. Randomly selected sample headings yield smaller test responses to the neuron's preferred heading when it is near the sample's heading direction and larger test responses to the preferred heading when it is far from the sample's heading. Limiting test stimuli to matching or opposite headings suppresses responses to preferred stimuli in both test conditions, whereas focusing on each neuron's preferred vs. antipreferred stimuli enhances responses to the antipreferred stimulus. Match vs. opposite paradigms create bimodal heading profiles shaped by interactions with late delay-period activity. We conclude that task contingencies, determining the prior probabilities of specific stimuli, interact with the monkeys' perceptual strategy for optic flow analysis. These influences shape attentional and working memory effects on the heading direction selectivities and preferences of MSTd neurons.

To investigate the role of the medial parietal region (MPR), comprising area 7 m and the retrosplenial and posterior cingulate cortices, in spatial navigation, we analyzed the spatial aspect of the responses of the MPR neurons in monkeys while they actively performed a navigation task in a virtual environment. One-third of the analyzed MPR neurons were activated depending on the location of the monkeys in the environment, that is, showed place-selective responses. Some neurons showed varying responses based on the starting point (SP) or destination. We further investigated the responses of the place-selective neurons when the monkeys were shown animations of the entire navigation route, including the preferred field, and a segment of the route, including an area around the preferred field, and a still image of the preferred field. We observed that the responses of some place-selective neurons reduced when the monkeys viewed the preferred field in the segmented animation or in the still image compared with when they viewed the entire animation. These results suggested that the knowledge about the SP or destination, that is, context, is necessary to activate place-selective neurons. The effect of such contextual information suggests that the MPR plays decisive roles in spatial processing such as navigation.

In this article, we will prove that the subsectors of $\alpha$-induced sectors for $M \rtimes \hat{G} \supset M$ forms a modular category, where $M \rtimes \hat{G}$ is the crossed product of $M$ by the group dual $\hat{G}$ of a finite group $G$. In fact, we will prove that it is equivalent to M\"uger's crossed product. By using this identification, we will exhibit an orbifold aspect of the quantum double of $\Delta$(not necessarily non-degenerate) obtained from a Longo-Rehren inclusion $A \supset B_\Delta$ under certain assumptions. We will apply the above description of the quantum double of $\Delta$ to the Reshetikhin-Turaev topological invariant of closed 3-manifolds, and we obtain a simpler formula, which is a degenerate version of Turaev's theorem that the Reshetikhin-Turaev invariant for the quantum double of a modular category $\hat{\Delta}$ is the product of Reshetikhin-Turaev invariant of $\hat{\Delta}$ and its complex conjugate., Comment: 19 pages

We examined visual response properties of single neurons in the parahippocampal (PH) cortex of alert monkeys using various visual stimuli (bars, geometrical shapes such as a circle, and images such as a human face) while the monkey fixated a spot for a juice reward. Of the investigated PH neurons 104 of 359 (29%) were found to be visually responsive. The investigation was focused on spatial and object aspects of visual processing. We investigated a visual receptive field (RF) property and a direction selectivity for a moving bar with respect to spatial processing. For half of these PH neurons (53%), the optimal stimulus position, where a visual stimulus elicited the maximal response, located peripherally, that is, with an eccentricity of more than 10 deg. More than 20% of these PH neurons had an RF that does not include the center of gaze. There were neurons in the PH cortex that appeared to convey motion signals. In addition, some PH neurons showed eye-position–dependent activity. With respect to object processing, we investigated selectivities for images, geographical shapes, orientations of a bar, and colors. For comparison purposes, we also examined responses of perirhinal (PR) neurons. PH neurons showed selective responses to these stimuli, but PR neurons were found to be more selective for images than PH neurons. These results suggest that the PH cortex is involved in both spatial and object processing, but less involved than the PR cortex in processing of complex images.

In this article, we discuss a (2 + 1)-dimensional topological quantum eld theory, for short TQFT, with a Verlinde basis. As a con- clusion of this general theory, we have a Dehn surgery formula. We show that Turaev-Viro-Ocneanu TQFT has a Verlinde basis. Several applica- tions of this theorem are exposed. Based on Izumi's data of subfactors, we list several computations of Turaev-Viro-Ocneanu invariants for some 3-manifolds. AMS Classication 57R56, 81T45; 46L37, 57M25, 57N10

In this paper, we establish a rigorous correspondence between the two tube algebras, that one comes from the Turaev-Viro-Ocneanu TQFT introduced by Ocneanu and another comes from the sector theory introduced by Izumi, and construct a canonical isomorphism between the centers of the two tube algebras, which is a conjugate linear isomorphism preserving the products of the two algebras and commuting with the actions of SL(2,Z). Via this correspondence and the Dehn surgery formula, we compute Turaev-Viro-Ocneanu invariants from several subfactors for basic 3-manifolds including lens spaces and Brieskorn 3-manifolds by using Izumi's data written in terms of sectors., 32 pages, 20 figures

Repeated recognition of the face of a familiar individual is known to show semantic repetition priming effect. In this study, normal subjects were repeatedly presented faces of their colleagues, and the effect of repetition on the regional cerebral blood flow change was measured using positron emission tomography. They repeated a set of three tasks: the familiar-face detection (F) task, the facial direction discrimination (D) task, and the perceptual control (C) task. During five repetitions of the F task, familiar faces were presented six times from different views in a pseudorandom order. Activation reduction through the repetition of the F tasks was observed in the bilateral anterior (anterolateral to the polar region) temporal cortices which are suggested to be involved in the access to the long-term memory concerning people. The bilateral amygdala, the hypothalamus, and the medial frontal cortices, were constantly activated during the F tasks, and considered to be associated with the behavioral significance of the presented familiar faces. Constant activation was also observed in the bilateral occipitotemporal regions and fusiform gyri and the right medial temporal regions during perception of the faces, and in the left medial temporal regions during the facial familiarity detection task, which are consistent with the results of previous functional brain imaging studies. The results have provided further information about the functional segregation of the anterior temporal regions in face recognition and long-term memory.

By measuring regional cerebral blood flow using PET, we delineated the roles of the occipito-temporal regions activated by faces and scenes. We asked right-handed normal subjects to perform three tasks using facial images as visual stimuli: in the face familiar/unfamiliar discrimination (FF) task, they discriminated the faces of their friends and associates from unfamiliar ones; in the face direction discrimination (FD) task, they discriminated the direction of each unfamiliar face; in the dot location discrimination (DL) task, they discriminated the location of a red dot on a scrambled face. The activity in each task was compared with that in the control fixation (CF) task, in which they fixated on the centre of a display without visual stimuli. The DL task activated the occipital cortices and posterior fusiform gyri bilaterally. During the FD task, the activation extended anteriorly in the right fusiform gyrus and laterally to the right inferior temporal cortex. The FF task further activated the right temporal pole. To examine whether the activation due to faces was face-specific, we used a scene familiar/unfamiliar discrimination (SF) task, in which the subjects discriminated familiar scenes from unfamiliar ones. Our results suggest that (i) the occipital cortices and posterior fusiform gyri non-selectively respond to faces, scrambled faces and scenes, and are involved mainly in the extraction of physical features of complex visual images; (ii) the right inferior temporal/fusiform gyrus responds selectively to faces but not to non-face stimuli and is involved in the visual processing related to face perception, whereas the bilateral parahippocampal gyri and parieto-occipital junctions respond selectively to scenes and are involved in processing related to scene perception; and (iii) the right temporal pole is activated during the discrimination of familiar faces and scenes from unfamiliar ones, and is probably involved in the recognition of familiar objects.

The pseudobinary compounds CeSi2−xGax were prepared, and the lattice parameters and the susceptibilities were measured. At the Si-rich end, 0≦x

Specific-heat and Cu NMR measurements have been made on the recently discovered heavy-electron compound CeCu 2 In. The low-temperature specific heat has an enormous electronic contribution with C el / T ≃1.2 J/mole·K 2 below 1.2 K, and shows a broad maximum at around 2.2 K. Below 2.3 K, Cu NMR linewidth Δ H shows appreciable additional broadening, and the nuclear transverse relaxation also becomes appreciably slower. These results indicate that CeCu 2 In undergoes an antiferromagnetic phase transition at T N ≃2.3 K. The possibility of ordering of quite a small moment is suggested from the observations of the gigantic value of C el / T below T N , the small magnetic entropy at T N , and the steady increase of C el / T through T N with decreasing temperature.

Resistivity, specific heat, and susceptibility studies on CeGe2 and its pseudobinary system Ce y La1−yGe2 are reported. The effective moment and the occurrence of ferromagnetic order (0.4≤y≤1.0) indicate the trivalence of Ce in the entirey range. However, the present results suggest that a Kondo effect coexists with the interionic ferromagnetic interaction; the magnetic entropy at the ordering temperatureT c is significantly lower thanR ln 2 (R is the gas constant) and the resistivity of La-diluted samples (y≤0.6) exhibits a Kondo-like minimum at about 10 K. The magnetic entropy atT c is related to the ratioTK/T c by a simple thermodynamic argument, whereTK is the Kondo temperature. TheTK is estimated to be about 2.7 K for 0.4≤y≤1.0, in fair agreement with what the resistivity anomaly suggests.

Single crystals of the ferromagnetic dense Kondo system CeSi x were grown, and the specific heat, the electrical resistivity and the magnetic susceptibility were measured. Electrical resistivity measurements clearly show the typical Kondo behavior, which unambiguously tells that CeSi x is a ferromagnetic dense Kondo system. The appreciable anisotropy of the magnetic susceptibility is analyzed with the crystalline field effect and a conjecture is made that the ground doublet is a \(\varGamma_{7}\)-like doublet.

Animals monitor the outcome of their choice and adjust subsequent choice behavior using the outcome information. Together with the anterior cingulate cortex (ACC), the lateral habenula (LHb) has recently attracted attention for its crucial role in monitoring negative outcome. To investigate their contributions to subsequent behavioral adjustment, we recorded single-unit activity from the LHb and ACC in monkeys performing a reversal learning task. The monkey was required to shift a previous choice to the alternative if the choice had been repeatedly unrewarded in past trials. We found that ACC neurons stored outcome information from several past trials, whereas LHb neurons detected the ongoing negative outcome with shorter latencies. ACC neurons, but not LHb neurons, signaled a behavioral shift in the next trial. Our findings suggest that, although both the LHb and the ACC represent signals associated with negative outcome, these structures contribute to subsequent behavioral adjustment in different ways., 負の経験から学ぶ脳のメカニズムを発見 --嫌なことを避ける学習のために二つの脳領域が役割を分担--. 京都大学プレスリリース. 2015-10-16.

In order to get further insight into the ground state energy level of CeSi x system, thermal expansion measurements have been performed for single crystalline CeSi1.86 and CeSi1.70. The results support the T7-like ground doublet which was conjectured from the susceptibility analysis. For CeSi1.70, the existence of the weak antiferromagnetic modulation found by neutron diffraction, has been studied with the magneto-caloric effect measurements to obtain the T-H phase diagram.