Head Swing Research Articles

Discovery of novel nematicidal active ingredient 2,4,7-trichloroquinazoline as a potential succinic dehydrogenase inhibitor

Plant-parasitic nematodes seriously affect the growth and yield of crops, causing huge economic losses to world agriculture. One of the effective ways to manage nematode diseases is the use of nematicides. Compound B1 was found to have good nematicidal activity in the biological test. Therefore, some compounds with similar structures to B1 were tested for better nematicidal activities. Among them, the LC50 of compound C3 against pine wood nematode (Bursaphelenchus xylophilus), rice stem nematode (Aphelenchoides besseyi), and sweet potato stem nematode (Ditylenchus destructor) were 4.6, 22.4, and 16.9 mg/L, respectively, which are markedly better than tioxazafen (103.9, 56.2, and 61.0 mg/L). Compound C3 was capable of not only significantly promoting oxidative stress in Bursaphelenchus xylophilus (B. xylophilus), but also curtailing population growth by influencing the frequency of head swing frequency, feeding behaviors, reproductive capabilities, and egg hatching rates. Furthermore, Compound C3 has demonstrated a favorable binding affinity to the succinic dehydrogenase (SDH) protein and has significantly dampened the activity of the SDH in B. xylophilus. Therefore, compound C3 can be used as a potential lead compound to discover new nematicides.

Multi-scale keypoints detection and motion features extraction in dairy cows using ResNet101-ASPP network

Detecting Keypoints in dairy cows aims to locate and track the motion trajectories of the body's joints, which plays a crucial role in behavior analysis and lameness detection. However, real farming scenarios, characterized by occlusions and large variations in object scale may result in poor detection results. Therefore we introduce the atrous spatial pyramid pooling (ASPP) module into the shallow network of ResNet101, designed to improve the multi-scale feature extraction capability of the model. The ASPP module enhances the robustness of recognition for different dimensional sizes and occluded keypoints using different dilatation rates in the parallel atrous convolutional layers to expand the model's receptive field. Furthermore, seven types of motion features, including tracking up, gait symmetry, step height balance, motion speed variability, head swing amplitude, head-neck slope and back curvature are extracted simultaneously by monitoring and tracking the motion trajectory of distinct keypoints. Several of these features represent innovative extraction models and attributes, first proposed in this study. Multiple models are trained and tested on datasets containing 2385 frames for ablation experiments. The experiments show that, in comparison with the ResNet50, MobileNet_v2_1.0, and EfficientNet-b0 backbone networks, the training error and test error of ResNet101 improve by 4.04–30.12 pixels and 3.81–28.14 pixels. Therefore, ResNet101 is used as the benchmark for subsequent model improvement by adding the ASPP module. The training error and test error of the ResNet101-ASPP network are improved by 0.27 and 0.24 pixels, respectively, compared to the benchmark network. The prediction confidence improves by 1.65-2.50% at three different dairy cow object scales, In addition, the keypoints under different occlusion conditions improve considerably, especially for small-scale keypoints, demonstrating the capability of the ASPP module for multi-scale feature extraction. By analyzing the distribution between the seven features and health, mild lameness, and severe lameness in dairy cows, it is shown that all the different features play an important role in distinguishing between different levels of lameness.

The tail segments are required by the performance but not the accomplishment of various modes of Drosophila larval locomotion

The tail plays important roles in locomotion control in many animals. But in animals with multiple body segments, the roles of the hind body segments and corresponding innervating neurons in locomotion control are not clear. Here, using the Drosophila larva as the model animal, we investigated the roles of the posterior terminal segments in various modes of locomotion and found that they participate in all of them. In forward crawling, paralysis of the larval tail by blocking the Abdb-Gal4 labeled neurons in the posterior segments of VNC led to a slower locomotion speed but did not prevent the initiation of forward peristalsis. In backward crawling, larvae with the Abdb-Gal4 neurons inhibited were unable to generate effective displacement although waves of backward peristalsis could be initiated and persist. In head swing where the movement of the tail is not obvious, disabling the larval tail by blocking Abdb-Gal4 neurons led to increased bending amplitude upon touching the head. In the case of larval lateral rolling, larval tail paralysis by inhibition of Abdb-Gal4 neurons did not prevent the accomplishment of rolling, but resulted in slower rolling speed. Our work reveals that the contribution of Drosophila larval posterior VNC segments and corresponding body segments in the tail to locomotion is comprehensive but could be compensated at least partially by other body segments. We suggest that the decentralization in locomotion control with respect to animal body parts helps to maintain the robustness of locomotion in multi-segment animals.

Design of intelligent desktop fan based on MQTT

At present, although the desktop fan has frequency conversion speed regulation, automatic head swing, remote control, etc., it is unable to learn the usage habits, lack of environmental perception, and lack of comprehensive analysis of data feedback, etc. This scheme proposes to design a desktop fan based on MQTT protocol and artificial intelligence principle, users learn from past operations, and predict user needs according to the existing sensor data. Intelligent analysis of the operating environment and status of the fan, timely shutdown or power adjustment, optimize the energy efficiency of the fan, through the deep application of advanced artificial intelligence technology, significantly improve the user experience.

A Soft Robotic Fish Actuated by Artificial Muscle Modules (SoRoFAAM-1)

In this paper, we present the design, fabrication, locomotion and bionic analysis of a Soft Robotic Fish Actuated by Artificial Muscle (SoRoFAAM). As a carangiform swimmer, the most important part of SoRoFAAM-1, on the motion point of view, is its tail designed around a bidirectional flexible bending actuator by layered bonding technology. This actuator is made of two artificial muscle modules based on Shape Memory Alloy (SMA) wires. Each artificial muscle module has four independent SMA-wire channels and is therefore capable of producing four different actuations. This design allows us to implement an adaptive regulated control strategy based on resistance feedback of the SMA wires to prevent them from overheating. To improve the actuation frequency to 2 Hz and the heat-dissipation ratio by 60%, we developed a round-robin heating strategy. Furthermore, the thermomechanical model of actuator is built, and the thermal transformation is analysed. The relationships between the actuation parameters and SoRoFAAM-1’s kinematic parameters are analysed. The versatility of the actuator endows SoRoFAAM-1 with cruise straight and turning abilities. Moreover, SoRoFAAM-1 has a good bionic fidelity; in particular, a maneuverability of 0.15, a head swing factor of 0.38 and a Strouhal number of 0.61.

Multi- and trans-generational effects of di-n-octyl phthalate on behavior, lifespan and reproduction of Caenorhabditis elegans through neural regulation and lipid metabolism

Di-n-octyl phthalate (DOP) is one important phthalate analog whose toxicities need comprehensive investigation to fully demonstrate phthalates health risks. In the present study, apical effects of DOP on behavior, lifespan and reproduction and the underlying mechanisms were explored in Caenorhabditis elegans for four consecutive generations (F1 to F4) and the trans-generational effects were also measured in the great-grand-children (T4 and T4′) of F1 and F4. Multi-generational results showed that DOP caused both stimulation and inhibition on head swing, body bending, reverse, Omega steering, pharyngeal pump and satiety quiescence. The stimulation and inhibition altered over concentrations and across generations, and the alteration was the greatest in reverse locomotion which showed both concentration-dependent hormesis and trans-hormesis. DOP stimulated lifespan and inhibited reproduction, showing trade-off relationships. Significant trans-generational residual effects were found in T4 and T4′ where the exposure was completed eliminated. Moreover, both similar and different effects were found in comparisons between F1 and F4, between F1 and T4, between F4 and T4′ and also between T4 and T4′. Further analysis showed close connections between effects of DOP on neurotransmitters (including dopamine, acetylcholine, γ-aminobutyric acid and serotonin) and enzymes in lipid metabolism (including lipase, acetyl CoA carboxylase, fatty acid synthetase, carnitine palmitoyl-transferase, glycerol phosphate acyltransferase and acetyl CoA synthetase). Moreover, the close connections were also found between biochemical and apical effects. Notably, the connections were different in multi- and trans-generational effects, which urged further studies to reveal the response strategies underlying the exposure scenarios.

Effects of tri-n-butyl phosphate (TnBP) on neurobehavior of Caenorhabditis elegans.

As an emerging flame retardant, organic phosphate flame retardants have been extensively used worldwide. The aim of this study is to determine the effects of TnBP on neurobehavior of Caenorhabditis elegans (C. elegans) and its mechanisms. L1 larvae of wild-type nematodes (N2) were exposed to TnBP of 0, 0.1, 1, 10, and 20 mg/L for 72 hours. Then, we observed that the body length and body width were inhibited, the head swings were increased, the pump contractions and chemical trend index were reduced, the production of reactive oxygen species (ROS) was increased, and the expression of mitochondrial oxidative stress related genes (mev-1 and gas-1) and P38 MAPK signal pathway-related genes (pmk-1, sek-1, and nsy-1) was altered. After reporter gene strains BZ555, DA1240, and EG1285 were exposed to TnBP of 0, 0.1, 1, 10, and 20 mg/L for 72 hours, the synthesis of dopamine, glutamate, and Gamma-Amino Butyric Acid (GABA) was increased. In addition, the pmk-1 mutants (KU25) led to the sensitivity of C. elegans to TnBP in terms of head swings. The results showed that TnBP had harmful effects on the neurobehavior of C. elegans, oxidative stress might be one of the mechanisms of its neurotoxicity, and P38 MAPK signal pathway might play an important regulatory role in this process. The results revealed the potential adverse effects of TnBP on the neurobehavior of C. elegans.

Automatic lameness scoring of dairy cows based on the analysis of head- and back-hoof linkage features using machine learning methods

Cow lameness is a complex locomotion behaviour, and effective characteristics are the key to identifying early lameness. Machine learning methods were used to quantify the movement of the hooves and head of cows, and they showed the possibility of using the head- and back-hoof linkage features extracted from motion analysis to classify early lameness. Firstly, the key points of the body in the side-view walking videos were tracked by DeepLabCut (DLC). Based on the curves of hoof movement and head swing, the head-hoof linkage pattern was analysed. Second, the curve of cow's back was extracted and the back-hoof linkage feature was built when the hoof touched the ground. At the same time, the movement curves were analysed to extract five other gait characteristics, including asymmetry of stride length, tracking up, asymmetry in the proportion of supporting phase, landing speed, and moving speed. Multiple models were trained on a dataset containing 212 videos, and 10-fold cross-validation was used to verify the performance of the algorithm. The classification performance was improved by optimising the model and algorithm. Overall accuracy and recall were 89.2% and 90.7%, respectively. The scores of the importance of features calculated by the Chi-square test showed that the head- and back-hoof linkage features play an important role in the classification of early lame cows. The hooves and their linkage features with the head and back of cows proposed in this paper can thus effectively detect early lameness in cows.

Research on Tracking and Identification of Typical Protective Behavior of Cows Based on DeepLabCut

In recent years, traditional farming methods have been increasingly replaced by more modern, intelligent farming techniques. This shift towards information and intelligence in farming is becoming a trend. When they are bitten by dinoflagellates, cows display stress behaviors, including tail wagging, head tossing, leg kicking, ear flapping, and skin fluttering. The study of cow protective behavior can indirectly reveal the health status of cows and their living patterns under different environmental conditions, allowing for the evaluation of the breeding environment and animal welfare status. In this study, we generated key point feature marker information using the DeepLabCut target detection algorithm and constructed the spatial relationship of cow feature marker points to detect the cow’s protective behavior based on the change in key elements of the cow’s head swinging and walking performance. The algorithm can detect the protective behavior of cows, with the detection accuracy reaching the level of manual detection. The next step in the research focuses on analyzing the differences in protective behaviors of cows in different environments, which can help in cow breed selection. It is an important guide for diagnosing the health status of cows and improving milk production in a practical setting.

Comparison of the chronic and multigenerational toxicity of racemic glufosinate and l-glufosinate to Caenorhabditis elegans at environmental concentrations

Glufosinate-ammonium, the second largest transgene crop resistant herbicide, is classified as a mobile persistent pollutant by the U.S. Environmental Protection Agencybecause of its slow decomposition and easy mobile transfer in a water environment. The chronic and multigeneration toxicity of this compound to environmental organisms are alarming. In this study, racemic glufosinate-ammonium and the effective isomer, l-glufosinate-ammonium, were used as the test agents. The developmental, neurotoxic and reproductive toxicities of Caenorhabditis elegans to their parents and progeny were studied by continuous exposure in water at concentrations of 0.1, 1, 10 and 100 μg/L. The causes of toxicity differences were analysed from oxidative stress and transcription levels. Through oxidative stress of C. elegans, racemic glufosinate-ammonium and l-glufosinate-ammonium both mediated the developmental toxicity (shortened developmental cycle, reduced body length and width, promoted ageingand decreased longevity), neurotoxicity (inhibited head swinging, body bending frequency and acetylcholinesterase [AchE] activity) and reproductive toxicity (significant reductions in the number of eggs and offspring in vivo and induced apoptosis of gonadal cells). These phenomena caused oxidative damage (protein and membrane lipid peroxidation) and further induced apoptosis. The changes in various indicators caused by racemic glufosinate-ammonium exposure were more significant than those caused by l-glufosinate-ammonium exposure, and the reproduction-related indicators were more significant than the developmental and neurological indicators. A continuous accumulation of toxicity was observed after multiple generations of continuous exposure. These research results provide a data reference for the ecotoxicological evaluation and risk assessment of glufosinate-ammonium and contribute to the revision and improvement of the related environmental policies of glufosinate-ammonium.

Regulatory roles of Bxy-laf-1 in reproductive behaviour of Bursaphelenchus xylophilus.

Bursaphelenchus xylophilu is a worldwide quarantine nematode, causing huge economic losses and ecological disasters in many countries. The sex ratio of B. xylophilus plays an important role in the nematode infestation. The laf-1-related genes are highly conserved in animals, playing crucial roles in sex determination. Therefore, we investigated the expression pattern and biological function of its orthologue, Bxy-laf-1 in B. xylophilus. Bxy-laf-1 has two typical conserved DNA-binding domains, DEAD and Helicase C. The real-time quantitative PCR data revealed that Bxy-laf-1 expression was required throughout the entire life of B. xylophilus, with the maximum expression in the J2 stage and the lowest expression in the adult stage. mRNA in situ hybridization showed that Bxy-laf-1 is mainly located in the cephalopharynx and reproductive organs of B. xylophilus. RNA interference (RNAi) indicated that the head swing frequency was dramatically decreased. The RNA interference results displayed that a significant reduction in motility was observed in the hatched larvae. The female to male sex ratio was also decreased in the F0 and F1 generations, but recovered in the F2 generation. The tail of female adults with eggs in the belly appeared deformities. This phenomenon appeared in the F0 and F1 generations, but recovered in the F2 generation. Bxy-laf-1 is a typical sex-determination gene with distinct expression patterns in males and females. As demonstrated in other species, the sex ratio was altered after knocking down Bxy-laf-1 expression. The results of this study contribute to our understanding of the molecular processes of Bxy-laf-1 in B. xylophilus, which may provide clues about how to control pine wilt disease by inhibiting ontogenic growth and reducing nematode fertility.

Design, synthesis and nematocidal activity of novel 1,2,4-oxadiazole derivatives with a 1,3,4-thiadiazole amide moiety

A series of novel 1,2,4-oxadiazole derivatives containing 1,3,4-thiadiazole amide group was synthesized and their nematocidal activities were evaluated. The results indicated that compounds 4-methoxy-N-(5-(((3-(p-tolyl)-1,2,4-oxadiazol-5-yl)methyl)thio)-1,3,4-thiadiazol-2-yl)benzamide 4i and N-(5-(((3-(4-chlorophenyl)-1,2,4-oxadiazol-5-yl)methyl)thio)-1,3,4-thiadiazol-2-yl)benzamilde 4p showed good nematocidal activity against Bursaphelenchus xylophilus. The corrected mortality of compounds 4i and 4p at 200 mg/L was 57.1% and 60.1%, respectively, which are much better than 13.5% of the commercial seed coating agent Tioxazafen. Compounds 4i and 4p dramatically decreased the head swinging, body fluctuation, and body bending frequency of B. xylophilus after 12 h of treatment. Moreover, they inhibited the respiration, decreased the oxygen consumption, and caused fluid leakage of B. xylophilus. In addition, compounds 4i and 4p have good druggability properties similar to those of Tioxazafen. The present work indicates that compounds 4i or 4p could be promising lead compounds for further development of nematicides.

Pulse rate estimation from forehead photoplethysmograph signal using RLS adaptive filtering with dynamical reference signal

Objective: Pulse rate (PR) extracted from Photoplethysmograph (PPG) is a significant feature in emotion recognition. However, PPG signal can be easily affected by the motion artifacts (MA) produced from the body movement and the random head swing of the subjects who are in Immersive Virtual Environments (IVE). The objective is to estimate PR from MA corrupted PPG signal.Methods: In order to reduce the influence of random MA, we propose a novel adaptive noise cancellation (ANC) method. This method could attenuate MA and reduce the execution time by adopting RLS adaptive filtering with dynamical reference signal (DRS-RLS). Then the spectral peak tracking with verification based on the Fast Fourier Transform (FFT) method is used to estimate PR value.Results: In this paper, the two-channel PPG signals and tri-axis acceleration signals were recorded synchronously from forehead by the virtual reality (VR) physiological helmet platform developed in our research center. Seventeen participants were able to observe and move randomly in four IVEs. The mean average absolute error (μAAE) using our proposed PR estimation method is 2.40 beats per minute (BPM). Furthermore, verification result of the proposed method on a public database of 22 PPG recordings showed the μAAE (2.01 BPM) and runtime (17.2 ms) of each time window.Conclusion: The proposed PR estimation method has achieved the lowest error compared with RLS adaptive filtering using fixed axis as reference signal or cascade RLS adaptive filtering. And the result has also shown a lower μAAE and less runtime than other adaptive filtering methods proposed in recent years.Significance: The proposed method in this paper has potential to be implemented in wearable devices due to its low error and low computation cost. It also provides a new way for reference signal selection of adaptive filtering.

Characterization of resistance to rice leaf folder,Cnaphalocrocis medinalis,in mutant Samba Mahsuri rice lines

AbstractThe rice leaf folder,Cnaphalocrocis medinalisGuenée (Lepidoptera: Crambidae), an important foliage feeding insect in rice,Oryza sativaL. (Poaceae), is widely distributed throughout Asia, causing frequent outbreaks and considerable yield losses. Mutants of the rice strain Samba Mahsuri (MSM) represent unique plant material and are explored here for the first time for resistance to the rice leaf folder. Stringent rapid field screening for two consecutive seasons led to the identification of 10 lines as moderately resistant, with low damage area as well as low damage score. Upon assessment of various morphological traits potentially contributing to the resistance, damage area was negatively correlated with leaf length and positively with leaf width. Among the biochemical traits, leaf nitrogen content was positively correlated with leaf folder damage whereas silica was negatively correlated. Oviposition preference by leaf folder adult moths and larval settling preference were low on MSM 139 and MSM 127. We also observed that leaf folder larvae took more time for leaf selection (3.1 min) and making a primary fold (41.5 min), with more head swings (846) in moderately resistant MSM lines. Similarly, in these lines, leaf folders showed a low intrinsic rate of increase (rm = 0.15 females per female per day), low weekly multiplication rate (2.85), and low net reproductive rate (R0 = 137.5 females per female per generation) with increased generation time (T = 32.8 days) and doubling time (4.5 days), indicating their relatively poor population growth potential. Overall, the moderately resistant mutant lines we identified showed reduced ovipositional preference and larval settling preference, extended larval developmental period with low survival, reduced primary fold length, and an increased number of binds and head swings with a low intrinsic rate of increase resulting in reduced population build‐up. These lines possessing a good genetic makeup have a great potential to be used in breeding programs for the development of leaf folder resistant varieties.

Optimization of In Vitro Culture Conditions for Production of Cordyceps bassiana Spores (Ascomycetes) and the Effect of Spore Extracts on the Health of Caenorhabditis elegans.

Cordyceps bassiana, an entomogenous fungus, has been used as a dietary therapeutic in traditional Chinese medicine for several millennia. However, naturally occurring C. bassiana is notably scarce in the field, especially at the spore stage. To date, there are few comprehensive studies on the biological characteristics and pharmacological attributes of C. bassiana spores. In this study, an isolate of C. bassiana (Bs1112) was identified as the teleomorph of Beauveria bassiana using morphology and rDNA internal transcribed spacer sequences. In vitro solid substrate fermentation parameters were evaluated; a rice substrate with 0.01% K+ achieved the maximum spore yield. High-performance liquid chromatography analysis of the bioactive components of C. bassiana spore powder (BC-CBSP), which was extracted using alcohol, showed that concentrations of adenosine were higher than concentrations of inosine, uridine, and cordycepin. The pharmacological impact of BC-CBSP was elucidated in a live animal model, Caenorhabditis elegans, at a range of concentrations from 0.145 to 14.5 mg/mL. The reproductive rate, frequency of head swinging and body bending (indicative of C. elegans locomotion), and lifespan of C. elegans were determined and compared with untreated populations. At the lowest concentration of BC-CBSP, reproduction was slowed but the number of eggs was not reduced. However, at both of the higher concentrations (1.45 and 14.5 mg/mL), BC-CBSP reduced the total number of eggs produced during the 8-day observation period. Furthermore, 0.145 mg/mL of BC-CBSP significantly increased the frequency of head swinging/body bending and the lifespan of C. elegans. This is the first report on the pharmacological effects of C. bassiana spores. Results suggest that low concentrations of BC-CBSP have no negative effects on the reproduction rate of C. elegans but could enhance nervous system activity and extend their lifespan.

Optimal Lighting of Optical Devices for Oral Cavity

Oral surgery mainly provides surgical scope illumination by doctors wearing headlamps, but there are still clinical restrictions on use. The limitations are (1) due to the angle of the head swing and the shadow of the visual field during the operation and (2) due to projection of the light source being worn on the doctor’s head and the length of the wire, and the fiber-optic wire will affect the relative position of the surgical instrument and limit the scope of the doctor’s activity. This study will focus on the development of oral lighting optical microstructure devices to solve and improve the abovementioned clinical use limitations. The production method is to make an oral lighting mold by 3D printing technology and use the polydimethylsiloxane (PDMS) of liquid silicone material to make an oral lighting device with mold casting technology. The results show that the optical simulation achieves the target light distribution by optimizing the three geometric reflection surfaces combined with the lens design by the optimization method, and the maximum illumination value can reach 5102 lux. According to the measurement results of mold casting technology, the average errors of the profile of the 3D printing finished product and the PDMS finished product of the oral device structure are about 1.4% and 16.9%, respectively. Because the contour of the PDMS finished product’s error caused the light to shift by 0.5∼3 mm distance, the light is still concentrated in the range of the tonsils, so this study can be defined as within the acceptable range of within 16.9% of the intra lighting error. The development of oral lighting devices in this study will reduce the burden on physicians in nonprofessional fields, reduce the time of surgery for patients to maintain the health of doctors, and rise the level of medical equipment to increase surgical safety.

The effect of head movement on the bounding gait of a quadruped robot with an active spine

It is a common phenomenon in the movement of the quadruped mammals accompanied with head swings. Inspired by this, this article attempts to add head motion to the bounding gait of a quadruped robot. According to the theoretical analysis, there are two main functions of the head. First, the head can realize the active control of the center of mass position of the robot, which is of great significance to the stable motion of the robot. Second, the swing of the head plays a role in regulating the pitch angle of the torso and improves the coordination and stability of the motion. A simplified quadruped robot model with a head and spine joint is established and analyzed theoretically. The regularity of head movement in periodic bounding gait is summarized. Through simulation and experiment, we confirm the two roles of the head in the bounding gait of a quadruped robot.

Different Dynamics of Sensory-Motor Development and Behavior During the Transitional Period in Puppies: Preliminary Results

Abstract Many studies have analyzed the behavior of puppies during their socialization period, while little attention has been paid to the transitional period, when vision and hearing develop. Here, we compared the average age of sensory and motor development, and the behavior among a total of 25 puppies. Each litter was videotaped during 1-hour daily sessions on postnatal days 10-21 and coded for the following mutually exclusive behavioral categories: sleeping, suckling and moving. The moving category included side-to-side head swinging, exploring, rolling and allogrooming. The opening of the eyelids, appearance of the startle response and ability to stand up with either the front or hind legs were identified. The duration and frequency of puppy behaviors varied significantly with breed and season of birth. Breed and gender differences in gross motor and sensory development were also observed. These findings may turn out to be crucial to enhance the welfare, standards of rearing, and behavioral interventions aimed at improving adaptability to novel stimuli in pet dogs.

Establishment of a novel rat model of blast-related diffuse axonal injury.

Although studies concerning blast-related traumatic brain injury (bTBI) have demonstrated the significance of diffuse axonal injury (DAI), no standard models for this type of injury have been widely accepted. The present study investigated a mechanism of inducing DAI through real blast injury, which was achieved by performing instantaneous high-speed swinging of the rat head, thus establishing a stable animal model of blast DAI. Adult Sprague-Dawley rats weighing 150±10 g were randomly divided into experimental (n=16), control (n=10) and sham control (n=6) groups. The frontal, parietal and occipital cortex of the rats in the experimental group were exposed, whereas those of the control group were unexposed; the sham control group rats were anesthetized and attached to the craniocerebral blast device without experiencing a blast. The rats were subjected to craniocerebral blast injury through a blast equivalent to 400 mg of trinitrotoluene using an electric detonator. Biomechanical parameters, and physical and behavioural changes of the sagittal head swing were measured using a high-speed camera. Magnetic resonance imaging (MRI) scans were conducted at 2, 12, 24 and 48 h after craniocerebral injury, only the experimental group indicated brain stem injury. The rats were sacrificed immediately following the MRI at 48 h for pathological examination of the brain stem using haematoxylin and eosin staining. The results indicated that 14 rats (87.5%) in the experimental group exhibited blast DAI, while no DAI was observed in the control and sham control groups, and the difference between the groups was significant (P<0.05). The present results indicated that this experimental design may serve to provide a stable model of blast DAI in rats.

외적 주의초점의 감각 정보 유형이 골프 퍼팅 학습과정에 미치는 영향

In the current study, the learning effect of three sensory types (visual, auditory, tactile) on external focus of attention on a 5 meter golf putting task was investigated. To learn the clubhead pendulum motion, the visual external focus group focused on a 1:1 ratio(backswing: follow-through) of putter head swing distance. The auditory external focus group performed putting tasks while synchronizing with consistent metronome sound(address, backswing start, impact). The tactile external focus group were focused on putter head weight during their practice session. Preliminary, acquisition phase, and retention tests were conducted during the evaluation procedure. A total of 90 trials (6 blocks of 15 trials) were conducted during the acquisition phase, and 15 trials were conducted during both preliminary and retention tests. There were no significant differences among the sensory groups in total, variable, and absolute errors during the acquisition phase. However, in the retention test, representing the learning effect, the tactile and auditory groups showed better performance than did the visual sensory group. These results suggest that movement demonstrations with limited visual information could delay learning, and that utilizing auditory and tactile information may enhance the learning effect. Further researches investigating the learning effect of sensory types on external focus of attention should be conducted for application in variety sports fields.