New discovery of the oldest maize weevils in the world from Jomon potteries, Japan

The maize weevil (_Sitophilus zeamais_) and rice weevil (_Sitophilus oryzae_) are two of the most damaging insects for stored grains, and are characteristic species of ancient Japan. Both species and the granary weevil (_Sitophilus granarius_) are common elsewhere in the world, but the natural distribution of maize and rice weevils is restricted to the Old World^1^. Japanese archaeological records contain a few maize weevil fossils after the Middle Yayoi period (ca. 2000 aBP)^2^. However, since evidence of weevils was discovered as impressions in Jomon potsherds in 2004^3^, many weevil impressions have been found. The oldest is from the Late Jomon (ca. 4000 to 3200 aBP). These findings and other archaeological evidence suggest that the maize weevil invaded Japan from Korea, accompanying the spread of rice cultivation^4^. However, in 2010 we discovered older weevil impressions dating to ca. 9000 aBP. These specimens are the oldest harmful insects discovered from archaeological sites around the world. The new discovery is valuable for future entomological research because such specimens are absent from the fossil record. It is also archaeologically and culturally interesting because this provides evidence of harmful insects living in Jomon villages. However, the new discovery raises the question of what these weevils infested: did cereal cultivation exist 9000 years ago? We have no persuasive answer, but hope one will be provided by future interdisciplinary collaborations among geneticists, entomologists, and archaeologists

Presetting of the Corticospinal Excitability in the Tibialis Anterior Muscle in Relation to Prediction of the Magnitude and Direction of Postural Perturbations

The prediction of upcoming perturbation modulates postural responses in the ankle muscles. The effects of this prediction on postural responses vary according to predictable factors. When the amplitude of perturbation can be predicted, the long-latency response is set at an appropriate size for the required response, whereas when the direction of perturbation can be predicted, there is no effect. The neural mechanisms underlying these phenomena are poorly understood. Here, we examined how the corticospinal excitability of the ankle muscles [i.e., the tibialis anterior (TA), the soleus (SOL), and the medial gastrocnemius (MG), with a focus on the TA], would be modulated in five experimental conditions: (1) No-perturbation; (2) Low (anterior translation with small amplitude); (3) High (anterior translation with large amplitude); (4) Posterior (posterior translation with large amplitude); and (5) Random (Low, High, and Posterior in randomized order). We measured the motor-evoked potentials (MEPs) induced by transcranial magnetic stimulation (TMS) at 50 ms before surface-translation in each condition. The electromyographic (EMG) responses evoked by surface-translations were also measured. The results showed that the TA-MEP amplitude was greater in the High condition (where the largest TA-EMG response was evoked among the five conditions) compared to that in the No-perturbation, Low, and Posterior conditions (High vs. No-perturbation, p < 0.001; High vs. Low, p = 0.001; High vs. Posterior, p = 0.001). In addition, the MEP amplitude in the Random condition was significantly greater than that in the No-perturbation and Low conditions (Random vs. No-perturbation, p = 0.002; Random vs. Low, p = 0.002). The EMG response in the TA evoked by perturbation was significantly smaller when a perturbation can be predicted (predictable vs. unpredictable, p < 0.001). In the SOL and MG muscles, no prominent modulations of the MEP amplitude or EMG response were observed, suggesting that the effects of prediction on corticospinal excitability differ between the dorsiflexor and plantar flexor muscles. These findings suggest that the corticospinal excitability in the TA is scaled in parallel with the prediction of the direction and magnitude of an upcoming perturbation in advance

Corticospinal excitability is modulated as a function of postural perturbation predictability

Recent studies demonstrated that the corticospinal pathway is one of the key nodes for the feedback control of human standing and that the excitability is flexibly changed according to the current state of posture. However, it has been unclear whether this pathway is also involved in a predictive control of human standing. Here, we investigated whether the corticospinal excitability of the soleus (SOL) and tibialis anterior (TA) muscles during standing would be modulated anticipatorily when perturbation was impending. We measured the motor-evoked potential (MEP) induced by transcranial magnetic stimulation over the motor cortex at six stimulus intensities. Three experimental conditions were set depending on predictabilities about perturbation occurrence and onset: No perturbation, No Cue, and Cue conditions. In the Cue condition, an acoustic signal was given as timing information of perturbation. The slope of the stimulus–response relation curve revealed that the TA-MEP was enhanced when postural perturbation was expected compared to when the perturbation was not expected (No Perturbation vs. No Cue, 0.023 ± 0.004 vs. 0.042 ± 0.007; No Perturbation vs. Cue, 0.023 ± 0.004 vs. 0.050 ± 0.009; Bonferroni correction, p = 0.01, respectively). In addition, two-way analysis of variance (intensity × condition) revealed the main effect of condition (F(1,13) = 6.31, p = 0.03) but not intensity and interaction when the MEP amplitude of the Cue and No Cue conditions was normalized by that in No Perturbation, suggesting the enhancement more apparent when timing information was given. The SOL-MEP was not modulated even when perturbation was expected, but it slightly reduced due to the timing information. The results of an additional experiment confirmed that the acoustic cue by itself did not affect the TA- and SOL-MEPs. Our findings suggest that a prediction of a future state of standing balance modulates the corticospinal excitability in the TA, and that the additional timing information facilitates this modulation. The corticospinal pathway thus appears to be involved in mechanisms of the predictive control as well as feedback control of standing posture

BATTING AND BUTTON-PRESS REACTION TIME IN PRIMARY, JUNIOR HIGH AND HIGH SCHOOL BASEBALL PLAYERS

The focus of this study was how baseball players acquire rapid visuo-motor processing during developmental stages. We compared simple and Go/Nogo reaction times in a button-press task and a swing-a-bat task between different age groups of teenage baseball players. Though reaction time, swing time and total reaction time were shorter in the older group, baseball-specific visuo-motor skills could not be investigated by our experiment. These results indicate that the general neural foundations underlying baseball performance develop over the school years

Neural effects of muscle stretching on the spinal reflexes in multiple lower-limb muscles

While previous studies have shown that muscle stretching suppresses monosynaptic spinal reflex excitability in stretched muscles, its effects on non-stretched muscles is still largely unknown. The purpose of this study was to examine the effects of muscle stretching on monosynaptic spinal reflex in non-stretched muscles. Ten healthy male subjects participated in this study. Muscle stretching of the right triceps surae muscle was performed using a motor torque device for 1 minute. Three different dorsiflexion torques (at approximately 5, 10, and 15 Nm) were applied during muscle stretching. Spinal reflexes evoked by transcutaneous spinal cord stimulation were recorded in both the lower-limb muscles before, during, and at 0 and 5 min following muscle stretching. The amplitudes of the spinal reflexes in both the stretched and non-stretched muscles in the right (ipsilateral) leg were smaller during stretching compared to before, and at 0 and 5 min after stretching. Furthermore, the degree of reduction in the amplitude of the spinal reflexes in the right (ipsilateral) leg muscles increased significantly as the dorsiflexion torque (i.e., stretching of the right triceps surae muscles) increased. In contrast, reduction in the amplitude of the spinal reflexes with increasing dorsiflexion torque was not seen in the left (contralateral) leg muscles. Our results clearly indicate that muscle stretching has inhibitory effects on monosynaptic spinal reflexes, not only in stretched muscles, but also in non-stretched muscles of the ipsilateral leg

PITCHING ACCURACY IN PROFFESSIONAL, HIGH SCHOOL AND JUNIOR HIGH SCHOOL PITCHERS

The purpose of this study was to investigate the differences in pitching accuracy among three different age groups. Professional (n=5), high school (n=8), and junior high school (n=11) pitchers were tested. To determine pitching accuracy, pitch locations relative to the catcher’s mitt were fitted to a bivariate normal distribution and a 90% confidence ellipse was obtained for each pitcher. Significant main effects were observed for age group in all of the parameters analysed, including: area, major radius and minor radius. There were significant differences in the minor and major radii of the 90% confidence ellipses between professional and junior high school players. The pitching accuracy of high school and professional players was also significantly greater than that of junior high school players. The superior pitching accuracy demonstrated by professional pitchers may be an important motor skill that is required to pitch at the professional level

S-1投与ラットにおける味覚障害の想定される末梢メカニズム

BACKGROUND: Taste disorders are frequently observed in cancer patients undergoing chemotherapy and are serious adverse events which impair the quality of life (QoL) of the cancer patient. Nevertheless, taste disorder mechanisms in cancer patients undergoing chemotherapy have not yet been fully elucidated. The aim of this study was to reveal taste disorder-related peripheral mechanisms using the two-bottle preference test (TBPT) and histological examination of tongues by hematoxylin-eosin staining and immunohistochemistry with protein-gene product 9.5. METHODS: In the TBPT, one bottle was filled with the 0.01 mM quinine hydrochloride (quinine), as a bitter compound, and the other was filled with water. Doses of 50 and 100 mg kg-1 day-1 S-1 (tegafur/gimeracil/oteracil potassium) are lethal to Wistar rats. Therefore, doses ranging from 2-20 mg kg-1 day-1 were administered to the rats for 3 weeks. The S-1 dose of 2 mg kg-1 day-1 corresponds to the clinical dose administered to cancer patients. The part of the tongue containing the circumvallate papillae was excised the following TBPT. RESULTS: The rate of increase in terms of the average preference rate for the quinine vs. all intake (quinine plus water) was significant from the initial S-1 period to the final one, compared with that in control rats, suggesting the possibility of a worsening sensation for the bitter taste. In S-1 rats, the area of taste nerve fibers were significantly decreased and the rate of degeneration of intra-tongue ganglionic nerve cells was significantly increased. These changes were significantly correlated with the rate of increase in average preference rate of the quinine. CONCLUSION: Neuropathy of the gustatory nerve at the periphery may be involved in taste disorders induced by an anticancer drug.博士（医学）・乙1329号・平成26年3月17

DEVELOPMENT OF THROWING ACCURACY IN ELEMENTARY SCHOOL HANDBALL PLAYERS

The purpose of this study was to investigate throwing accuracy in children aged 7-12 belonging to hand ball dub team. Participants were divided into three age groups and performed 30 overhand throws. Three sessions in each of 3 conditions of optimum, accurate, and speed conscious throws to a target 7m from the thrower were examined. Throw Location (TL), Ball Speed and Radial Error (RE) were obtained from each session. The minimum RE was 20.9cm performed by a 12 years old girl in the accuracy conscious session. The significant differences were observed for age groups in all of the three conditions analysed. In age of 11-12, speed-accuracy trade-off was observed. The current data showed distribution of TL became smaller with older age, indicating development of accuracy. The greater development was observed between age 7 to 9 compared to age 9 to 12

Generation of High-Purity Millimeter-Wave Orbital Angular Momentum Modes Using Horn Antenna: Theory and Implementation

Twisted electromagnetic waves, of which the helical phase front is called orbital angular momentum (OAM), have been recently explored for quantum information, high speed communication and radar detections. In this context, generation of high purity waves carrying OAM is of great significance and challenge from low frequency band to optical area. Here, a novel strategy of mode combination method is proposed to generate twisted waves with arbitrary order of OAM index. The higher order mode of a circular horn antenna is used to generate the twisted waves with quite high purity. The proposed strategy is verified with theoretical analysis, numerical simulation and experiments. A circular horn antenna operating at millimeter wave band is designed, fabricated, and measured. Two twisted waves with OAM index of l=+1 and l=-1 with a mode purity as high as 87% are obtained. Compared with the other OAM antennas, the antenna proposed here owns a high antenna gain (over 12 dBi) and wide operating bandwidth (over 15%). The high mode purity, high antenna gain and wide operating band make the antenna suitable for the twisted-wave applications, not only in the microwave and millimeter wave band, but also in the terahertz band.Comment: 18 pages, 9 figure

Effects of Aquatic Pole Walking on the Reduction of Spastic Hypertonia in a Patient with Hemiplegia: A Case Study

Here we report an acute effect of aquatic pole walking (PW) training intervention on a 64-year-old male patient with chronic hemiparesis and symptoms of spasticity in the right lower limb. A comparison of over ground walking before and after 20 minutes of aquatic PW training revealed a significant improvement in gait performance. As a main result, the average speed of walking after the intervention was 0.16 m/s after the intervention as compared to 0.04 m/s in the initial condition. The time taken for each stride cycle was drastically decreased, mainly due to shortening of the stance time. Underlying the improved gait performance was the emergence of functional muscle activity in the paralyzed and spastic leg muscles. The result observed in this patient should be further tested among a large population of patients presenting similar symptoms. Moreover, the basic mechanisms underlying aquatic PW intervention should be further elucidated