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The face is an important cue for discriminating conspecifics in some primates (including humans), other mammals and birds. Although there is considerable evidence that fish can discriminate between conspecifics based on familiarity, the actual traits used to do so remain unclear. However, recent studies showed that two cichlid species used face colour patterns similarly to other vertebrates, and have suggested that social signals have evolved around the eyes, even in fish (face-specific hypothesis). In this study, we tested whether the striped, rock-dwelling Tanganyikan cichlid Julidochromis transcriptus can discriminate between familiar and unfamiliar conspecifics using facial patterns alone. We used a monitor to present fish with four digital models of combinations of facial and body patterns from familiar and unfamiliar fish. Focal fish spent more time near the monitor when presented with unfamiliar face models regardless of the body pattern. Therefore, we concluded that J. transcriptus recognizes familiar conspecifics using facial patterns alone, despite having distinct stripe patterns on the whole body. Our results are consistent with the face-specific hypothesis and indicate that social signals have evolved around the eyes of fish.

This study represents cases with spontaneous neuritis of peripheral nerves in electric eels. Two electric eels were presented with abnormal swimming behavior and loss of appetite. Electric eels had extensive histopathologic lesions in the splenic and cardiac nerves. The lesions were characterized by swelling of neuronal cells, central chromatolysis and marked inflammatory cell infiltration consisting mainly of lymphocytes around the affected nerves. To the best of our knowledge, this is the first case report of spontaneous neuritis of peripheral nerves in electric eels.

This study represents cases with spontaneous neuritis of peripheral nerves in electric eels. Two electric eels were presented with abnormal swimming behavior and loss of appetite. Electric eels had extensive histopathologic lesions in the splenic and cardiac nerves. The lesions were characterized by swelling of neuronal cells, central chromatolysis and marked inflammatory cell infiltration consisting mainly of lymphocytes around the affected nerves. To the best of our knowledge, this is the first case report of spontaneous neuritis of peripheral nerves in electric eels.

In this paper, we propose a method for detecting vehicles from a nighttime driving scene taken by an in-vehicle monocular camera. Since it is difficult to recognize the shape of the vehicles during nighttime, vehicle detection is based on the headlights and the taillights, which are bright areas of pixels called blobs. Many research studies using automatic multilevel thresholding are being conducted, but these methods are prone to get affected by the ambient light because it uses the luminance of the whole image to derive the thresholds. Owing to such reasons, we focused on the Laplacian of Gaussian operator, which derives the response of luminance difference between the blob and its surroundings. Compared with automatic multilevel thresholding, Laplacian of Gaussian operator is more robust to the ambient light. However, the computational cost to derive the response of this operator is large. Therefore, we used a method called Center Surround Extremas to detect the blobs in high speed. Since the detected blobs include nuisance lights, we had to determine whether the blob is a light of a vehicle or not. Thus, we classified them according to the features of the blob using support vector machines. Then, we detected vehicle traffic lane and specified the region where the vehicle may exist. Finally, we classified the blobs based on the movements across the frames. We applied the proposed method to nighttime driving sequences and confirmed the effectiveness of the classification process used in this method and that it could process within frame rate.

The theoretical underpinnings of the mechanisms of sociality, e.g. territoriality, hierarchy, and reciprocity, are based on assumptions of individual recognition. While behavioural evidence suggests individual recognition is widespread, the cues that animals use to recognise individuals are established in only a handful of systems. Here, we use digital models to demonstrate that facial features are the visual cue used for individual recognition in the social fish Neolamprologus pulcher. Focal fish were exposed to digital images showing four different combinations of familiar and unfamiliar face and body colorations. Focal fish attended to digital models with unfamiliar faces longer and from a further distance to the model than to models with familiar faces. These results strongly suggest that fish can distinguish individuals accurately using facial colour patterns. Our observations also suggest that fish are able to rapidly (≤ 0.5 sec) discriminate between familiar and unfamiliar individuals, a speed of recognition comparable to primates including humans. published

Fiber-reinforced composite materials often exhibit nonlinear stress-strain behavior under the combined tension-compression and shear with respect to the transverse direction to the fiber. This paper focuses on the mechanical description of the nonlinear inelastic behavior of CFRP. In order to obtain fundamental data to elucidate the inelastic behaviors of the composite, quasi-static failure tests were firstly performed on unidirectional and symmetric angle-ply laminate tubes with different fiber orientations. Then, the flow rules proposed by Chow et al. were modified and developed to describe the non-linear mechanical behavior of symmetric angle-ply laminates under multi-axial loading. Comparison between the experimental data and the theoretical predictions showed that the proposed theory can appropriately describe the inelastic behavior of CFRP.

The authors reported the results of field survey and family follow-up on acatalasemia and hy- pocatalasemia during the year of 1965. No hypocatalasemic case was seen in the tests of 2, 897 individuals at two places of Japan Proper. And a hypocatalasemic boy was found out among 10, 083 children of Miyako Is., Ryukyu. In 1965, ten acatalasemias of six families at various parts in the world were added to the for- merly known cases. Consequently, the total of reported acatalase- mias amounted to 90 cases of 43 families by the end of 1965.