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The internal representation of a path shape is an element that constructs an internal representation of an entire route or environment. In the present study, we examined the ability of rats to discriminate path shapes. The rats learned to discriminate between an oval-shaped runway and a square-shaped one and to respond to one of two response boxes on the two sides of the runways. After the learning sessions, we tested which of the inner and outer walls the rats used as cues for discrimination using different wall shapes. The results suggest that the rats used the shape of the inner walls for the discrimination. Subsequently, the learning sessions, in which different shapes of the inner and outer walls were used, continued. There was a tendency for the rats to show better performance when the shape of the inner walls was congruent with the rule in the original learning, suggesting again that the rats used the shape of the inner wall for the discrimination. In addition, similar results were obtained when the task was conducted in the dark, suggesting that rats can discriminate path shapes using non-visual information.

We have developed an open-source software called CrySPY, which is a crystal structure prediction tool written in Python 3, and runs on Unix/Linux platforms. CrySPY enables anyone to easily perform ...

To investigate the effects of retrosplenial cortex (RSC) lesions on episodic-like memory, we used four types of object recognition tasks. What task examined memory of object identities. Where task examined memory of object locations. When task examined memory of the temporal order of presented objects. Episodic task examined the integrated memory of the identity, location, and temporal order of presented objects. Rats with the RSC lesions preferred novel objects in the What and Where tasks, whereas they showed no such preference in the When and Episodic tasks, suggesting that rats with the RSC lesions have deficits in memory for temporal order and that this might cause deficits in episodic-like memory.

The affiliative effect of oxytocin on behavior toward other individuals can be modulated by positive and negative aspects of those individuals. However, the context-dependent effect of oxytocin on helping behavior is still unclear. In this study, we examined the effect of oxytocin administration on helping behavior in rats. The rats learned to open a door to help a cagemate soaked with water. The rats were divided into Pair and Solo groups. The rats in the Pair group were housed with their cagemates and those in the Solo group were housed individually. The rats in both groups received oxytocin (1.0 mg/kg) or saline injections intraperitoneally for 5 consecutive days before starting the experimental sessions. In the rats injected with oxytocin, the Solo group showed helping behavior faster than those in the Pair group. The results suggest that the effects of oxytocin administration on helping behavior are dependent on the social context.

Polar metal is a material that hosts both polar distortion and metallicity. Such a material is expected to show exotic magneto-electric phenomena if it superconducts. Here, we theoretically explore ferroelectric and superconducting properties in a series of perovskite-type oxyhydrides $A\mathrm{Ti}{\mathrm{O}}_{2}\mathrm{H}$ ($A=\mathrm{K}$, Rb, Cs) under hole-doping conditions using first-principles calculations based on density functional theory. Our simulation shows that these compounds host spontaneous polarization and superconductivity at optimal doping concentration. The unusual coexistence of superconductivity and large polarization ($\ensuremath{\sim}100\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{C}/\mathrm{c}{\mathrm{m}}^{2}$) originates from the weak coupling of the polar distortion and superconducting states, the reason for which is the separation of the displaced atoms and spatially confined metallic carriers. Additionally, superconductivity is enhanced by the unique electronic properties near the valence band maximum: quartic band dispersion with a sizable contribution of hydrogen $1s$ states. This paper thus features the oxyhydrides as possible model polar superconducting systems, which may be utilizable for future magneto-electric devices.

SummarySeveral studies suggest that rodents show empathic responses and helping behavior toward others. We examined whether prairie voles (Microtus ochrogaster) would help conspecifics who were soaked in water by opening a door to a safe area. Door-opening latency decreased as task sessions progressed. When the conspecific was not soaked in water, the latency of the door-opening did not decrease, indicating that the distress of the conspecific is necessary for the learning of the door-opening. These suggest that prairie voles learn helping behavior. We found no sex difference in the door-opening latency or the interest in other voles soaked in water. Additionally, we also examined the helping behavior in prairie voles in which oxytocin receptors were genetically knocked out. Oxytocin receptor knockout voles demonstrated less learning of the door-opening and less interest in other voles soaked in water. This suggests that oxytocin is important for the emergence of helping behavior.

We perform a crystal structure search using Bayesian optimization and evaluate its efficiency with a varying parameter value in the descriptor. Applying the crystal structure search to crystalline silicon shows that the efficiency of the search depends heavily on the parameter value. We find that the efficiency is linked to the distribution of the descriptor. Therefore, we introduce an information measure of the distribution to estimate an appropriate parameter value for performing the crystal structure search efficiently. The measure can also be used to predetermine an appropriate parameter value. The validity of the measure is confirmed with its applications to silicon oxide and yttrium-cobalt alloy.

The treatment of vertical bone defects caused by severe periodontal disease requires the regeneration of periodontal tissue. Although various bone substitutes have been clinically applied to vertical bone defect correction, the evaluation of these materials in periodontal tissue remains incomplete. The purpose of this study was to examine the bone regeneration abilities of various bone substitutes including Cytrans, Cerasorb, Neobone and Bio-Oss in a 3-wall bone defect animal model. All of these bone substitutes showed a similar healing ability to periodontal ligament and cementum. However, Cytrans showed the fastest bone healing ability compared with the other materials at 4 weeks post-transplantation. In addition, the recruitment of osteoclasts and endothelial cells was observed in Cytrans grafts at 4 weeks, but only detected at 8 weeks in the other materials. These results suggest that Cytrans promotes faster bone healing by inducing bone remodeling and angiogenesis.

To examine the flexibility of rats' spatial behaviour, we required rats to navigate to one of four boxes on the corners of a lattice maze. The maze consisted of five vertical and five horizontal corridors on a plane parallel to the ground and allowed us to design diverse routes. One box was set as goal and the other three were set as starting points. Both the time to arrive at the goal and the number of errors at the intersections on the route decreased, suggesting that the rats learned the route. As the goal boxes were successively changed, the decrease in the errors and the time to reach the goal became faster. This suggests that the rats learned the spatial layout of the maze, i.e., developed a cognitive map. We then carried out a shortcut test by removing one wall located near the centre of the maze. The rats took the shortcut route when passing through the location around the removed wall made the entire route shorter, but did not pass through the location when passing through the location made the entire route longer. These suggest that rats can flexibly utilize their internal representation of a spatial structure to respond to a change in a learned environment.

Mere exposure effect refers to a phenomenon in which repeated stimuli are evaluated more positively than novel stimuli. We investigated whether this effect occurs for internally generated visual representations (i.e., visual images). In an exposure phase, a 5 × 5 dot array was presented, and a pair of dots corresponding to the neighboring vertices of an invisible polygon was sequentially flashed (in red), creating an invisible polygon. In Experiments 1, 2, and 4, participants visualized and memorized the shapes of invisible polygons based on different sequences of flashed dots, whereas in Experiment 3, participants only memorized positions of these dots. In a subsequent rating phase, participants visualized the shape of the invisible polygon from allocations of numerical characters on its vertices, and then rated their preference for invisible polygons (Experiments 1, 2, and 3). In contrast, in Experiment 4, participants rated the preference for visible polygons. Results showed that the mere exposure effect appeared only when participants visualized the shape of invisible polygons in both the exposure and rating phases (Experiments 1 and 2), suggesting that the mere exposure effect occurred for internalized visual images. This implies that the sensory inputs from repeated stimuli play a minor role in the mere exposure effect. Absence of the mere exposure effect in Experiment 4 suggests that the consistency of processing between exposure and rating phases plays an important role in the mere exposure effect.

Empathy toward the distress of others is thought to motivate helping behaviour, in the form of voluntary action to eliminate that distress. Neuropeptide oxytocin is associated with various social cognitive abilities, including empathy and prosocial behaviour. The anterior cingulate cortex is known to be one of the brain regions underlying empathy, and one in which oxytocin receptors are expressed. However, the relationship between helping behaviour and oxytocin in the anterior cingulate cortex is still unclear. The present study investigated whether oxytocin in the anterior cingulate cortex is involved in rats' helping behaviour. In Experiment 1, we examined the influence of blockading the oxytocin receptors in the anterior cingulate cortex on helping behaviour. Impeding oxytocin in the anterior cingulate cortex delayed learning of the helping behaviour. In Experiment 2, we examined immunofluorescent colocalization of oxytocin receptors and c-fos proteins in the anterior cingulate cortex, the anterior insular cortex, and the amygdala in rats that acquired helping behaviour. We found increased c-fos expression in oxytocin receptor-containing neurons in the anterior cingulate cortex and amygdala when the rats acquired helping behaviour. In addition, the change in neural activation was found in the late phase of the learning. These results suggest that the oxytocin in the cingulate-amygdala pathways may play an important role in helping behaviour.

We will review a notion of Morita equivalence between subfactors, which is a variation of Morita equivalence in ring and module theory. The main result is stated as follows: for arbitrary two Morita equivalent subfactors of hyperfinite $\mathrm{II}_1$ factors with finite Jones index and finite depth we can always choose a finite dimensional nondegenerate commuting square which gives rise to the subfactors isomorphic to the original ones. As an application of Morita equivalence between subfactors in connection with recent developments of theory of finite dimensional weak $C^*$-Hopf algebras, we will make a brief comment about the 3-dimensional topological quantum field theories obtained from subfactors with finite index and finite depth.

We propose a crystal structure prediction method based on Bayesian optimization. Our method is classified as a selection-type algorithm which is different from evolution-type algorithms such as an evolutionary algorithm and particle swarm optimization. Crystal structure prediction with Bayesian optimization can efficiently select the most stable structure from a large number of candidate structures with a lower number of searching trials using a machine learning technique. Crystal structure prediction using Bayesian optimization combined with random search is applied to known systems such as NaCl and ${\mathrm{Y}}_{2}{\mathrm{Co}}_{17}$ to discuss the efficiency of Bayesian optimization. These results demonstrate that Bayesian optimization can significantly reduce the number of searching trials required to find the global minimum structure by 30--40% in comparison with pure random search, which leads to much less computational cost.

The dorsal anterior cingulate cortex (dACC) plays crucial roles in monitoring the outcome of a choice and adjusting a subsequent choice behavior based on the outcome information. In the present study, we investigated how different types of dACC neurons, that is, putative pyramidal neurons and putative inhibitory interneurons, contribute to these processes. We analyzed single-unit database obtained from the dACC in monkeys performing a reversal learning task. The monkey was required to adjust choice behavior from past outcome experiences. Depending on their action potential waveforms, the recorded neurons were classified into putative pyramidal neurons and putative inhibitory interneurons. We found that these neurons do not equally contribute to outcome monitoring and behavioral adjustment. Although both neuron types evenly responded to the current outcome, a larger proportion of putative inhibitory interneurons than putative pyramidal neurons stored the information about the past outcome. The putative inhibitory interneurons further represented choice-related signals more frequently, such as whether the monkey would shift the last choice to an alternative at the next choice opportunity. Our findings suggest that putative inhibitory interneurons, which are thought not to project to brain areas outside the dACC, preferentially transmit signals that would adjust choice behavior based on past outcome experiences.

A daily eatable candy that has possible protective activity against oral candidiasis was experimentally produced. The candy was made from reduced-maltose as main constituent and from several natural products, such as oligonol (depolymerized polyphenols derived from lychee), cinnamon (cassia), citral, and capric acid, which are known to have anti-Candida activity in vitro and in vivo. The candy effectively inhibited the mycelial growth of C. albicans, even when it was diluted 1,000 times with culture media. We assessed the protective activity of the candy against murine candidiasis. When 50μl of candy dissolved and diluted 4 times with water was administered 3 times into the oral cavity of Candida infected mice, the score of lesions on the Candida-infected tongues improved on day 2. These findings suggest that this candy has potential as food that provides protective activity against oral candidiasis.

A series of unsynthesized perovskite-type oxyhydrides ATiO

Attentional inhibition that occurs during discrimination tasks leads to the negative evaluation of distractor stimuli. This phenomenon, known as the distractor devaluation effect also occurs when go/no-go tasks require response inhibition. However, it remains unclear whether there are interactions between attention and response controls when the distractor devaluation effect occurs. The aims of this study were to investigate whether attention to stimuli in the go/no-go task plays a facilitative role in distractor devaluation through response inhibition, and to clarify whether this effect reflects a decreased preference for no-go stimuli. Participants evaluated the preference for pictures before and after a go/no-go task. In Experiments 1 and 2, they made a go or no-go response depending on the category of pictures displayed (gummy candies or rice crackers), whereas in Experiment 3 they did on the basis digit category, even or odd numbers, superimposed on such pictures. Experiments 1 and 2 demonstrated that the pictures presented as no-go stimuli in the preceding go/no-go task were evaluated as less positive than the pictures presented as go stimuli. This devaluation effect reflected an increased preference for the go stimuli but not a decreased preference for the no-go stimuli. Experiment 3 indicated that response inhibition did not affect the preference for the pictures that had not received attention in a preceding go/no-go task. These results suggest that although attention plays an important role in differential ratings for go and no-go stimuli, such differences, in fact, reflect the valuation of go stimuli.

Thiabendazole (TBZ), a pesticide with antifungal activity, was detected in toasted and seasoned laver which had been reported as tasting unpleasant by consumers in March 2008. From a survey of the manufacturing process, it was concluded that the TBZ contamination had originated from a sponge-roller which was used to paste seasoned liquid onto the toasted laver. At that time it was found that TBZ is widely used to prevent fungal contamination of sponge-rollers. For further survey of TBZ contamination in the laver, we developed a more sensitive detection method using LC-MS/MS. With our new method, six commercial products harvested in March 2008 and July 2009, respectively, were tested. Five out of six samples harvested in 2008 were positive for TBZ, with values in the range from 0.014 to 1.736 µg/g. Only one sample harvested in 2009 contained a detectable level of TBZ. The data obtained here contributed to the improvement of the manufacturing process.

Visual cues about self-movement are derived from the patterns of optic flow and the relative motion of discrete objects. We recorded dorsal medial superior temporal (MSTd) cortical neurons in monkeys that held centered visual fixation while viewing optic flow and object motion stimuli simulating the self-movement cues seen during translation on a circular path. Twenty stimulus configurations presented naturalistic combinations of optic flow with superimposed objects that simulated either earth-fixed landmark objects or independently moving animate objects. Landmarks and animate objects yield the same response interactions with optic flow; mainly additive effects, with a substantial number of sub- and super-additive responses. Sub- and super-additive interactions reflect each neuron's local and global motion sensitivities: Local motion sensitivity is based on the spatial arrangement of directions created by object motion and the surrounding optic flow. Global motion sensitivity is based on the temporal sequence of self-movement headings that define a simulated path through the environment. We conclude that MST neurons' spatio-temporal response properties combine object motion and optic flow cues to represent self-movement in diverse, naturalistic circumstances.

Episodic memory is defined as a memory system that consciously carries out recollecting one's subjective past experience and re-experiencing it. Through these mental activities, episodic memory is thought to make mental time travel retrospectively and prospectively possible, which is sometimes considered to be unique to humans. However, after a seminal study in scrub-jays by Clayton & Dickinson (1998), animal models of episodic memory have been developing and are starting to affect the concept of human episodic memory itself. This paper will concentrate on reviewing the studies that could encourage nonhuman animals to utilize memory — the properties are consistent with current definition of human episodic memory. Additionally, a discussion on the possibility to divide the system of episodic memory into two sub-processes and to study in animals the sub-processes of episodic memory will be undertaken.

This paper reviews our progress on the high-T c superconducting (HTS) sampler development, covering from the circuit design to the latest experimental data in the sinusoidal and pulse waveform measurements. A computer simulation has revealed that our sampler circuit with an improved design enables waveform measurement with the bandwidth over 100 GHz even with the thermal noise at around 40 K. Using the HTS sampler circuits fabricated employing an improved layout, we demonstrated waveform measurements for sinusoidal signals with frequencies of up to 50 GHz, the upper limit of the signal generator we used, both in the voltage-input-type system with a high-frequency input line and in the current-input-type one with a superconducting pickup coil. In the pulse measurement using an on-chip sampler, we succeeded in observing pico-second-order-wide single flux quantum (SFQ) current pulses, suggesting the potential bandwidth of our HTS sampler of more than 125 GHz.

Erratum to: Anim CognDOI 10.1007/s10071-015-0872-2. The authors would like to correct the word "less" to "more" in the sentence under the heading "Results and discussion". The correct sentence should read as: This indicates that the soaked rats spent more time in the pool area than did the helper rats.

A daily eatable candy that has possible protective activity against oral candidiasis was experimentally produced. The candy was made from reduced-maltose as main constituent and from several natural products, such as oligonol (depolymerized polyphenols derived from lychee), cinnamon (cassia), citral, and capric acid, which are known to have anti-Candida activity in vitro and in vivo. The candy effectively inhibited the mycelial growth of C. albicans, even when it was diluted 1,000 times with culture media. We assessed the protective activity of the candy against murine candidiasis. When 50μl of candy dissolved and diluted 4 times with water was administered 3 times into the oral cavity of Candida infected mice, the score of lesions on the Candida-infected tongues improved on day 2. These findings suggest that this candy has potential as food that provides protective activity against oral candidiasis.

In this paper, we establish the general theory of ( 2 + 1 ) -dimensional topological quantum field theory (in short, TQFT) with a Verlinde basis. It is a consequence that we have a Dehn surgery formula for 3-manifold invariants for this kind of TQFT's. We will show that Turaev–Viro–Ocneanu unitary TQFT's obtained from subfactors satisfy the axioms of TQFT's with Verlinde bases. Hence, in a Turaev–Viro–Ocneanu TQFT, we have a Dehn surgery formula for 3-manifolds. It turns out that this Dehn surgery formula is nothing but the formula of the Reshetikhin–Turaev invariant constructed from a tube system, which is a modular category corresponding to the quantum double construction of a C * -tensor category. In Sato and Wakui (J. Knot Theory Ramif. 12 (2003) 543), we will exhibit computations of Turaev–Viro–Ocneanu invariants for several “basic 3-manifolds”. In the appendix, we discuss the relationship between the system of M ∞ - M ∞ bimodules arising from the asymptotic inclusion M ∨ M op ⊂ M ∞ constructed from N ⊂ M and the tube system obtained from a subfactor N ⊂ M .

To determine whether monkeys can navigate a virtual environment, and whether they can represent a virtual environment in their brain, we trained two macaque monkeys to perform a navigation task in a virtual building and conducted behavioral analyses. After learning the task from the first starting point, they were trained to perform the navigation task from a second starting point which is already familiar to them during the first training session. The second training was completed faster than the first one. Furthermore, we found that the time required for a free-way-finding test from a novel starting point was shortened after the second training. These results suggest that monkeys can navigate a virtual environment and can construct a flexible representation of a virtual environment in their brain.