Straight Legs Research Articles

The activity of the cardiovascular system of women during the performance of special running exercises: pilot study

Relevance. Currently, there is no knowledge of what kind of stress the cardiovascular system is subjected to during special running exercises (SBU), how prolonged running exercises affect the heart rate (HR). So, it remains unexplored: what is the average heart rate (HRSsr) characteristic of the SBU, what maximum values it can reach during the performance of a particular running exercise, which does not allow them to be used reasonably to achieve certain goals in the process of physical training.The purpose of this study was to study the functioning of the cardiovascular system of women during special running exercises.Methods and organization of research. To achieve this goal, an experiment was conducted in which 6 women participated. Before the test procedure, the subjects performed a workout that included a fiveminute slow run and flexibility exercises. Then, the subjects in cross-country shoes performed the following complex of running and running exercises: slow running, running with a whip of the shin, running on straight legs, running with a high knee lift, rolling from toe to toe, mincing running, jumping, fast running, the length of the distance at which they performedThere was a run and the SBU was 100 meters. Polar heart rate monitors and chest heart rate sensors H9 were used to determine heart rate indicators.Conclusions. The results of the experiment showed that most of the exercises aimed at developing speed and strength abilities turned out to be more stressful compared to exercises aimed at developing endurance. Thus, using special basic exercises in the process of physical training in order to develop physical qualities, it is necessary to take into account the peculiarities of the activity of the cardiovascular system during their performance, and depending on the level of preparedness of those involved, it is necessary to regulate the intensity of physical activity by changing various characteristics: the length of the distance of performance, the number of repetitions, rest intervals, or the pace of performing special running exercises.

Criterion Validity of Accelerometers in Determining Knee-Flexion Angles During Sitting in a Laboratory Setting

Introduction: Device-based monitors often classify all sedentary positions as the sitting posture, but sitting with bent or straight legs may exhibit unique physiological and biomechanical effects. The classifications of the specific nuances of sitting have not been understood. The purpose of this study was to validate a dual-monitor approach from a trimonitor configuration measuring knee-flexion angles compared to motion capture (criterion) during sitting in laboratory setting. Methods: Nineteen adults (12♀, 24 ± 4 years) wore three activPALs (torso, thigh, tibia) while 14 motion capture cameras simultaneously tracked 15 markers located on bony landmarks. Each participant completed a 45-s supine resting period and eight, 45-s seated trials at different knee flexion angles (15° increment between 0° and 105°, determined via goniometry), followed by 15 s of standing. Validity was assessed via Friedman’s test (adjusted p value = .006), mean absolute error, Bland–Altman analyses, equivalence testing, and intraclass correlation. Results: Compared to motion capture, the calculated angles from activPALs were not different during 15°–90° (all, p ≥ .009), underestimated at 105° (p = .002) and overestimated at 0°, as well as the supine position (both, p < .001). Knee angles between 15° and 105° exhibited a mean absolute error of ∼5°, but knee angles <15° exhibited larger degrees of error (∼10°). A proportional (β = −0.12, p < .001) bias was observed, but a fixed (0.5° ± 1.7°, p = .405) bias did not exist. In equivalence testing, the activPALs were statistically equivalent to motion capture across 30°–105°. Strong agreement between the activPALs and motion capture was observed (intraclass correlation = .97, p < .001). Conclusions: The usage of a three-activPAL configuration detecting seated knee-flexion angles in free-living conditions is promising.

Determining the traditional methods used by newborn women by giving birth: a descriptive study

Objectives: This study was carried out to determine the traditional practices that women who have just given birth apply to their babies. Methods: The research is descriptive. The participants were recruited from women who had just given birth to 198 women in a maternity hospital. The data was collected through the personal information form. The chi-square test was used to plan the categorical data in detail as the mean of the research data, as numbers, and as percentages. p < 0.05 was accepted as meaning. Results: It was determined that traditional practices frequently used by women; The use of the yellow blanket against jaundice, swaddling so that the waist does not sink in, staying warm, being hard as steel, and having straight legs and the use of salt. It was determined that these practices were applied more by mothers who graduated from primary school. Although the frequency of use of applications such as burying the belly in the garden and throwing it in the water was found to be significant by age, it was determined to be used more in the group aged 31 and over. It has been determined that wearing evil eye beads is more common among mothers under the age of 25. Conclusions: In our study, it was observed that traditional practices were widely applied in the neonatal period. Newborn health should be supported by providing continuous midwifery care to women, education, and health checks.

The influence of sub-technique and skiing velocity on air drag in skating style cross-country skiing

In cross-country skiing, velocities range from 2 m s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{s}}^{-1}$$\\end{document} up to more than 20 m s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{s}}^{-1}$$\\end{document} across undulating terrain, and aerodynamics can, therefore, make a large impact on performance. The aim of this study was to investigate the influence of skiing velocity on air drag for skating sub-techniques and downhill postures (tuck). Dynamic and static drag measurements for two athletes were performed in a wind tunnel in relevant velocity ranges for each sub-technique. The drag area decreased with velocity from 2 m s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{s}}^{-1}$$\\end{document} to around 10–12 m s-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extrm{s}}^{-1}$$\\end{document}, where it plateaued. No difference in air drag was found between the sub-techniques performed in upright postures (G2–G4) and thereby relatively similar frontal areas. In the G5 sub-technique performed without poling action in a lower posture, the reduced air drag was approximately 28% lower than for G2–G4 at similar velocities, and could even be reduced by an additional 21.7% by keeping the arms tucked in front of the body. In the downhill tucked postures, athletes could reduce air drag by 23% by keeping a low tuck, compared to a high tuck with straight legs. The sub-techniques were tested both dynamically and by averaging the static positions throughout the movements. The air drag was on average 6.1% lower for dynamic movements, indicating that dynamical movements like in cross-country skiing should be tested dynamically when evaluating air drag. Finally, the chosen cycle rate had minimal influence on air drag.

Design, Control, and Validation of a Symmetrical Hip and Straight-Legged Vertically-Compliant Bipedal Robot.

This paper presents the development, modeling, and control of L03, an underactuated 3D bipedal robot with symmetrical hips and straight legs. This innovative design requires only five actuators, two for the legs and three for the hips. This paper is divided into three parts: (1) mechanism design and kinematic analysis; (2) trajectory planning for the center of mass and foot landing points based on the Divergent Component of Motion (DCM), enabling lateral and forward walking capabilities for the robot; and (3) gait stability analysis through prototype experiments. The primary focus of this study is to explore the application of underactuated symmetrical designs and determine the number of motors required to achieve omnidirectional movement of a bipedal robot. Our simulation and experimental results demonstrate that L03 achieves simple walking with a stable and consistent gait. Due to its lightweight construction, low leg inertia, and straight-legged design, L03 can achieve ground perception and gentle ground contact without the need for force sensors. Compared to existing bipedal robots, L03 closely adheres to the characteristics of the linear inverted pendulum model, making it an invaluable platform for future algorithm research.

Comparison of Limb and Joint Strengths between Tai Chi Chuan Players and Non-Tai Chi Chuan Groups by Using a Force Sensor

Background: Tai Chi Chuan (TCC) is popular in exercise, but little research has been done on limb and joint strength after the exercise. This study aimed to investigate whether TCC players have different limb and joint strengths in the upper and lower limbs from non-Tai Chi Chuan (NTCC). Methods: Twenty TCC players who have at least one year of experience playing TCC were compared with a group of 25 NTCC participants. A force sensor was used to measure forces in the lower and upper limbs. Maximum forces produced by the lower limbs was measured during a standing position with straight legs or were measured in a seated position. The maximum forces produced by the upper limbs were measured in a standing position at elbow and shoulder levels. Results: The forces of the knee extensors in the TCC group were significantly higher (7.4%) than in the NTCC group; however, the forces of the knee flexors in the TCC group were significantly lower than the NTCC group. The heel-force in hip extension in the NTCC group was significantly higher (9.3%) than in TCC; the toe-force in the plantar flexion in the NTCC was significantly higher than in the TCC group. There were no significant differences between the two groups in the hand-forces in the upper limbs. Conclusions: TCC routine movements strengthen the muscles related to knee extension, which are mainly related to bending knee performance during TCC exercise. For the healthy people between 42 and 78 years old, TCC benefits the enhancement of the strength for knee extension but not for the knee flexion, ankle plantar flexion and hip extension. There is no significant difference between the TCC and NTCC groups on the strength of upper limbs and joints. As a whole, the effect of Tai Chi Chuan exercise on the strengths in the limbs and joints is compromised. In the future, a study with larger sample size than this study is highly recommended.

Differentiated approach to the motor activity organization of students in the process of physical education at the university

Introduction. The World Health Organization notes the current increase in the physical inactivity of the population. Despite the generally recognized potential of physical education, there is a global decline in its implementation. This situation is fueling a global health crisis – a conservative estimate of 6% of all deaths in the world is the result of physical inactivity. The purpose of the study is to test the methodology of a differentiated approach to the motor activity organization of students in the process of physical education at the university. Materials and Methods. The experiment involved 20 students of the Chechen State Pedagogical University aged 18 to 24 years. To assess the level of physical fitness tests of the TRP standard set were selected before and after the experiment. They included 30-meter run (sec.); flexion and extension of the arms in emphasis lying on the floor (number of times); tilt forward from a standing position with straight legs on the gymnastic bench (see); shuttle run 3x10 m. (sec.); lifting the torso from a supine position (number of times in 1 minute); long jump from a place with a push with two legs (see). Methods of mathematical statistics including methods of descriptive statistics (arithmetic mean, standard deviation); Wilcoxon statistical test were applied. Results. Implementation of various options for building a weekly motor regimen for students was envisaged at the formative stage of the study. The analysis of the dynamics of indicators over the period of the experiment revealed positive changes in all three groups, however, a significant increase was observed in the first experimental group in all control exercises (p < 0.01). This indicates a significant advantage of the motor activity mode used in the 1st experimental group, which allowed students to successfully come close to the standards for obtaining the golden badge of distinction of the TRP complex, despite the low initial level of physical fitness. Conclusion. The mode of five-time lessons of a weekly microstructure providing a high level of students' physical fitness is the best option in the conditions of intensification of the learning process and an organized mode of students’ motor activity.

A comparative study of vertical jump parameters in men's college basketball and volleyball players

This study aimed to compare lower limb strength disparities between male college volleyball and basketball players in four distinct vertical jump types. We recruited 100 second-level (above the national standard) male college athletes (50 basketball and 50 volleyball players) from Capital University of Physical Education and Sports who volunteered to participate. We assessed the performance of each athlete with regards to the squat jump (SJ), countermovement jump (CMJ), continuous jump with straight legs (CJs), and continuous jump with bent legs (CJb). Data analysis was performed by independent samples t-tests in SPSS version 25.0. software. In the CMJ test, volleyball players had a significantly higher vertical jump displacement (VJD; p = 0.047, t = −2.018), squat displacement (SD; p = 0.005, t = −2.883), peak force (p = 0.023, t = −1.964), and peak velocity (p = 0.011, t = −1.687) than basketball players. In the SJ test, volleyball players had a significantly higher VJD (p = 0.041, t = −1.21) and SD (p = 0.008, t = −1.46) than basketball players. In the CJs test, volleyball players had a significantly higher average vertical jump displacement (AVJD; p = 0.042, t = −2.067) than basketball players. In the CJb test, volleyball players had a significantly higher AVJD (p = 0.001, t = −3.448), average squat displacement (p = 0.017, t = −2.44), and average contact time (p = 0.045, t = −2.038) than basketball players. The overall vertical jump ability of college volleyball players was better than that of college basketball players. CMJ, SJ, CJs and CJb training should be included in daily training sessions and considered in the selection of basketball and volleyball players. In addition, coaches can use fast twitch Fibers, the effect of pre-stretch and k as the main evaluation indicators to assess daily training progress.

The effects of experimental program on the explosive strength of lower limbs in male adolescents

Background and Study Aim. Various experimental programs for the development of motor skills are present in sports activities. Explosive strength can be defined as the ability to produce maximum force as soon as possible, and it represents an essential factor in activities where it is necessary to increase the acceleration of the body mass, the mass of specific body parts, or of an external object. The aim of study – to determine the effects of an experimental program on the explosive strength of lower limbs in male adolescents.
 Material and Methods. One hundred and one male adolescent (aged 19 years ± 6 months; body height 181.43 ± 7.42 cm; body mass 80.08 ± 10.07 kg) were recruited and randomly divided into two groups: experimental group (E; N=48) and control group (K; N=48). The E group performed the experimental program which lasted fifteen weeks and consisted of three 60-min training sessions per week. All participants were tested on Squat Jump (SJ), Countermovement Jump (CMJ), Countermovement Jump with arms (CMJa) and Continuous Jump with Straight Legs (CJSL). The four tests were performed using a Kistler force platform to measure Quatro Jump Bosco Protocol Version 1.0.9.2 and gave us data about the jump height, number of jumps for 15s, average power jump and peak power jump. The multivariate analysis covariance (MANCOVA) and follow up analysis covariance (ANCOVA) were used to analyze the data.
 Results. The results of MANCOVA showed statistically significant differences (p ≤ 0.001) between the E and K groups in all systems of variable lower limb explosive strength in male adolescents. In addition, results of ANCOVA showed statistically significant differences (p ≤ 0.001) in SJ, CMJ, CMJa and CJSL in favor of the E group compared to the K one.
 Conclusions. The results of this research show that a fifteen-week experimental program can lead to significant improvements in lower limb explosive strength in male adolescents.

Adjustment of patterns of women’s trousers on the baseof the lower body

This article presents the influence of female lower body characteristics as a waist position to the bottom of thefoot on the design of women’s trousers. First, the author designs patterns for people with straight legs. Second,the product will wear on people with bow legs, X-legs, and people who have big waists and small thighs. Third,the author analyzes the fit of each pattern in every sample and gives directions for pattern correction. Finally,the samples are sewn again until they fit samples and are not wrinkles. The anthropometric theoretical researchmethod is used in the product fit analysis. The theory designs trousers pattern that is used to design patterns forpeople who have straight legs. The experimental research method is used to conduct actual surveys on 40 peoplefrom four groups with different lower body parts through the Likert scale for five evaluation criteria on five levels.The survey results are analyzed on the SPSS software. The results show that Cronbach’s alpha index is over 0.7.Research has made practical contributions in the field of garment product design as well as consulting customerswhen buying and selling clothes.

Effect of jump heights, landing techniques, and participants on vertical ground reaction force and loading rate during landing on three different Korean teeterboards

Korean teeterboard is one of the most physically and technically demanding circus disciplines. Two performers take turns jumping vertically and land with high impact. The aims of this study were to (1) compare the stiffness across three different teeterboards, and (2) compare Peak Landing Force (PLF) and Maximal Loading Rate (MLR) of four acrobats performing jumps from three teeterboards using four landing techniques (normal, smooth, straight legs, and empty board). Pressure sensors were used to determine recorded forces under the feet, while Boosted Regression Trees (BRT) was used to analyze factors contributing to PLF and MLR. Standard static loading protocol was used to estimate teeterboard stiffness. PLF and MLR increased with jump height. PLF and MLR were reached when landing on the teeterboard with the highest stiffness. The “normal” and “straight legs” landing techniques were associated with higher PLF and MLR. The BRT model was able to associate both PLF and MLR with jump height, participant, teeterboard, and landing technique factors. PLF reached 13.5 times the body weight when landing on the stiffer teeterboard using the straight legs technique. Trainers should be aware of the injury risk to teeterboard acrobats during landing.

Islamic Values of the Peta Kapanca Tradition at the Mbojo Tribe's Marriage, West Nusa Tenggara, Indonesia

For the Bima people, the Mbojo tribe's Peta Kapanca tradition has very sacred symbols and meanings that must be carried out in every wedding procession. The Peta Kapanca tradition not only reveals a cultural identity and marriage tradition, but it also examines the Islamic values that are embedded in it. The objectives of this paper was to see how the Peta Kapanca tradition was carried out at Mbojo Tribe weddings in terms of procession and Islamic values. This is a descriptive qualitative study using an ethnographic approach. The findings show that the process of implementing the Peta Kapanca tradition at a Mbojo Tribe wedding is as follows: (1) the prospective bride sits on the stage (uma ruka), (2) the straight hand is placed on a pillow on the banana leaf, and the straight legs are straight and grounded with banana leaves, (3) the divine kalam is read, followed by the remembrance of Kapanca in the form of istigfar, creed, prayers, recitation of the verses of the Qur'an, and (4) crushing henna leaves which are mashed in the palms of the bride-to-be. This Peta Kapanca's cultural process contains good values such as aqidah, worship, and moral values.

Evaluation of the Results of Rehabilitation of Chronic Low Back Pain Syndrome in Physically Active and Inactive Patients During Leisure Time

Introduction: Movement is one of the main, modifiable factors (behaviour-dependent) that affects the health and quality of life of individuals and the entire population. Physical activity, including evidence-based active rehabilitation, is the subject of many studies on the prevention and treatment of spinal disorders, which are some of the most serious health problems. The largest group of people with spinal disorders are patients suffering from Nonspecific Low Back Pain (ang. Nonspecific Low Back Pain – NLBP), with kinesitherapy having the widest application in the chronic pain phase. A significant part of the research is devoted to the problem of movement in patients with chronic non-specific low back pain (CNLBP). One physiotherapy treatment method used in chronic low back pain syndrome is the DBC method. It is based on a detailed functional diagnosis, answers given to a standardized questionnaire, individualized treatment plans and active exercises with spinal resistance using specialized DBC equipment. Aim: The aim of this study was to evaluate the influence of leisure-time physical activity on the results of the DBC functional restoration program in patients with chronic, non-specific, low back pain after outpatient rehabilitation. The researchers tested the hypothesis that patients with regular physical activity attained better results of functional restoration compared to physically inactive participants. M aterials and Methods: The research group was comprised of one-hundred forty-seven participants. All subjects suffered from low back pain syndrome lasting for a period of at least three months without neurological symptoms. All symptoms were non-specific. The subjects were divided into two groups. Group 1 was comprised of participants who undertake regular physical activity for more than 45-minutes per exercise session, at least twice a week. Participants in Group 2 did not undertake any physical activity other than that resulting from everyday activities. The study commenced with an interview and standardized DBC questionnaire to get participants’ subjective assessment of the following parameters: current level of pain, functional limitations and scale of depression. A clinical trial was conducted prior to the measurement of objective parameters in order to exclude radicular pain (Lasegue test). Next, the objective parameters were measured: bioelectric activity of the lumbar erector spinae muscles (ang. surfasce electromyography – sEMG) on the right and left side in two positions: standing upright and leaning forward with straight legs. Also, DBC devices were used to measure the following range of motion of the lumbo-thoracic spine: flexion, extension, rotation and lateral flexion/bending. Upon completing the tests (Test 1) both groups were subject to active DBC therapeutic treatment. The therapy consisted of 12 meetings carried out within a 6 week period. Each session lasted for 1.5 hours. When the treatments ended testing was repeated for each group (Test 2). Results: Mean values of functional parameters of the lumbar spine were calculated for both groups. Statistical significance was determined between the preliminary (Test 1) and final (Test 2) tests. All the objective parameters in Group 1 showed statistically significant improvement post-therapy. Different results were observed in Group 2 for participants who did not perform regular physical activity. Although all parameters improved, only some achieved statistical significance. Significance between the two groups was also studied at the beginning of the experiment (Test 1) and after its completion (Test 2). There results showed no statistically significant difference in values of some objective parameters prior to the treatment, while some parameters differed. The treatment achieved a statistically significant improvement in the “active” group compared to the “inactive” one in almost every tested parameter excluding the extension. Significant differences between the groups were observed in the subjective parameters such as: functional limitations (ADL) (ang. Activity of Daily Living – ADL) and level of depression both in the first and last tests. Conclusions: Patients with chronic non-specific low back pain syndrome who remain physically active in leisure time and participated in the 6-week DBC rehabilitation program achieved a statistically significant improvement in the functional parameters of the spine. Patients with chronic non-specific low back pain syndrome who remain physically active in leisure time and participated in the 6-week DBC rehabilitation program improved more in the objective and subjective functional parameters of the spine in comparison with the inactive participants. Active leisure time contributes to the efficacy of physiotherapy for people with low back disorders.

Linear type trait evaluation of firstborns of Ukrainian Black-and-White Dairy breed depending on the body build

It has been experimentally proven that the strength and direction of the connection between the linear type traits evaluation of the Ukrainian black-and-white dairy breed cows and their body build depends on the type of the build and the sign of the exterior. The study was conducted in 2018 on a breeding plant of the Ukrainian Black-and-White Dairy breed SPC named Shchorsa in Kiev region (n=89). Differentiation of cows on types of their body build was conducted by the method proposed by Chernenko (low-capacity, mid-capacity and high-capacity types) and Kolesnik (by the massiveness index – on the friable and dense, the bone index – delicate and rough, the wide-breast and wide-rump indices – on narrow-body and wide-body types). It was found that the cow-heiferswere well-developed, had intermediate stature and optimum body condition score, deep body, and wide, slight slope rump. They alsohad desirable rear legs, set and foot angle but some toe-out, the udder was well-balanced. Under the good total score of the exterior of studied cows there were some animals with short stature (134– 136 cm), very wide rump, straight rear legs side view and toe-out, extremely steep foot angle, loose fore udder attachment, deep udder below hocks and front teat placement inside of quarter. The degree of development of the studied linear traits of cow-heifers confirms their in-herd variability. The variability of the exterior traits varies from 10,7 % (body depth) to 38,6 % (stature). In addition to the stature of a significant variability was characterized of angularity (22,4 %), rear legs set (22,5 %), body condition score (21,8 %), as well as traits that describe udder: rear udder attachment (31,4 %), udder depth (32,6 %) and front and rear teat position (31,3 % and 25,1 %, respectively). The high variability of linear traits indicates the possibility of effective their selection. As a result of the research, it has been established that the strength and direction of the correlations between the linear type traits evaluation of Ukrainian Black-and-White Dairy breed cows and the type of their body build depends on the type of the body build and the linear trait. The low-, mid- and high-capacity bodies build types (according to Chernenko) reliably correlate with chest width (r=0,58) and body depth (r=0,48), rear legs rear view (r=0,30), the central ligament (r=0,28), udder depth (r =-0,22) and teat length (r=0,25), P˂0,01–0,001. Friable and dense bodies build (according to Kolesnik) were most strongly associated with stature (r=-0,28), chest width (r =-0,70), and body depth (r=-0,38), as well as with rear legs rear view (r=-0,23), P˂0,05...0,001; delicate and rough bodies build – with stature (r=-0,51), angularity (r=-0,22),rump width (r=-0,35), udder depth (r=-0,27) and rear udder attachment (r =0,20), P ˂ 0,05–0,001; narrow-body and wide-body types – with chest width (r=0,30) and rump width (r=0,23), P˂0,05–0,01. Linear type trait evaluation of cows depends on the body build. The strength and direction of the correlations between types of body build and linear traits showed that the most informative is the classification of the body build by low-, mid- and high-capacity according to Chernenko – on the average η2x=17,5 %. The less informative – by narrow-body and wide-body types according to Kolesnik – η2x=7,6 %. The classification of cows on delicate-rough, narrow-body and wide-body types (according to Kolesnik) according to informativeness and reliability can have the intermediate position – η2x=10,0–11,5 %. The strongest influence on the body build has the cows’ height (η2x=27,9 % on average for all studied types of body build), chest width (η2x=33,5 %), body depth (η2x=21,8 %), rump width (η2x=24,1 %) and rear legs (η2x=18,7 %). Key words: cows, linear type trait evaluation, body build, correlation, power of influence.

The range of normative surface skin temperature changes in adolescents: prospective multicenter study.

We aimed to establish a normative range of surface skin temperature (SST) changes due to blood redistribution in adolescents and to register the time needed for complete postural change-related blood redistribution. The healthy volunteers (age 15-18, n = 500, M 217, F 283) were recruited for this prospective multicenter study. The volunteers were asked to keep one extremity down and another extremity up in supine rest, sitting with straight legs, and upright rest. We obtained temperature readings being taken from the tips of the middle fingers and temperature readings from the tips of the first toes at the ambient temperature of 25 °C and 30 °C. The control group consisted of a 100 of adult volunteers. The resting temperature of the middle fingers for a sitting participant was 28.6 ± 0.8 °C. The physiological change of this temperature during body position changes was 4.5 ± 1.1 °C and for most of the participants remained within the 26.5-31.5 °C range at 25 °C. For the toe, physiological skin temperature range was 25.5-33 °C. At 30 °C, these ranges were 27-33 °C for the fingers and 27-34 °C for the toes. On average, 2-3 min were needed for such temperature changes. At normal room temperature, the SST of thermoneutral adolescents may vary within a range of approximately 5 °C only due to the blood redistribution in the body. This range is specific for each person due to individual peculiarities of the vasomotor activity. This normative range of SSTs should be taken into account during investigations of thermoregulation.

Ergonomic conditions in manual harvesting in Swedish outdoor cultivation.

Ergonomic problems in manual labour in agriculture are well known worldwide. This study investigates the ergonomic conditions during manual work in Swedish outdoor vegetable/berry cultivation. A questionnaire on work and health conditions was sent to all growers of vegetables and strawberries in Sweden. Workplace studies with video recordings and observations of work operations and positions at harvest were performed. Calculations of back compression and risk assessment for harmful impact of work were made. Employers and employees were interviewed. Working standing/walking instead of kneeling when harvesting vegetables was shown to decrease lumbar compression. Using a conveyor belt instead of carrying a plastic box into the field for the harvested vegetables reduced harmful forward bends and the risk of musculoskeletal disorders (MSD). When strawberries were grown in pots, the work position was a straight back and neck, with lowered arms. When grown on raised beds, the work position was either kneeling or bending forward with straight legs. When kneeling, the back was often bent or rotated, frequently with the arms far from the body. Bending forward with straight legs caused a harmful level of lumbar compression. Harmful work postures arise during manual harvesting in Swedish outdoor cultivation. The risk can be reduced using mechanized work tools and optimal cultivation methods. Adequate work training, including instructions about optimal working postures and movements, may reduce the risk of MSD, but will most likely not eliminate it completely.

Advances in stereotactic navigation for pelvic surgery

BackgroundStereotactic navigation could improve the quality of surgery for rectal cancer. Critical challenges related to soft tissue stereotactic pelvic navigation include the potential difference in patient anatomy between intraoperative lithotomy and preoperative supine position for imaging. The objective of this study was to determine the difference in patient anatomy, sacral tilt, and skin fiducial position between these different patient positions and to investigate the feasibility and optimal set-up for stereotactic pelvic navigation.MethodsFour consecutive human anatomical specimens were submitted to repeated CT-scans in a supine and several degrees of lithotomy position. Patient anatomy, sacral tilt, and skin fiducial position were compared by means of an image computing platform. In two specimens, a 10-degree wedge was introduced to reduce the natural tilt of the sacrum during the shift from supine to lithotomy position. A simulation of laparoscopic and transanal surgical procedures was performed to assess the accuracy of the stereotactic navigation.ResultsAn up-to-supracentimetric change in patient anatomy was noted between different patient positions. This observation was minimized through the application of a wedge. When switching from supine to another position, sacral retroversion occurred independent of the use of a wedge. There was considerable skin fiducial motion between different positions. Accurate stereotactic navigation was obtained with the least registration error (1.9 mm) when the position of the anatomical specimen was registered in a supine position with straight legs, without pneumoperitoneum, using a conventional CT-scan with an identical specimen positioning.ConclusionThe change in patient anatomy is small during the sacral tilt induced by positional changes when using a 10-degree wedge, allowing for an accurate stereotactic surgical navigation. This opens up new promising opportunities to increase the quality of surgery for rectal cancer cases where it is difficult or impossible to identify and dissect along the anatomical planes.

Fabrication and Evaluation of PCB-Embedded Broadband Signal Transformers With Custom Machined Racetrack-Shaped Ferrite Cores for Ethernet Applications

To reduce the manufacturing variability in broadband ferrite-core magnetic components such as ethernet transformers, there is great industry interest in the embedding of the core materials within a planar substrate and fabricating the windings using high-precision photolithography. An embedding process has been previously developed and found to impose design restrictions on embedded devices that can be feasibly fabricated. It was previously found that a racetrack core shape (toroidal halves joined by straight legs) allows the most efficient use of area to embed multiple magnetic devices with maximum inductance. In this paper, three different sizes of racetrack-shaped cores were fabricated from bulk ferrite. The racetrack cores were then embedded within printed circuit board substrate, wound as transformers, and measured to evaluate bandwidth and inductance. It was found that the transformer mutual inductance was significantly reduced through the embedding process. However, the devices were found to exhibit excellent broadband coupling behavior. Certain designs of transformers met the inductance and bandwidth requirements of 100 and 1000Base-T ethernet.

Inductance optimization of miniature Broadband transformers with racetrack shaped ferrite cores for Ethernet applications

There is strong commercial interest in the ability to fabricate the windings of traditional miniature wire-wound inductive circuit components, such as Ethernet transformers, lithographically. For greater inductance devices, thick cores are required, making the process of embedding the ferrite material within circuit board one of few options for lithographic winding fabrication. In this paper, a non-traditional core shape, suitable for embedding in circuit board, is examined analytically and experimentally; the racetrack shape is two halves of a toroid connected by straight legs. With regard to the high inductance requirements for Ethernet applications (350μH), the racetrack transformer inductance is analytically optimized, determining the optimal physical dimensions. Two sizes of racetrack-core transformers were fabricated and measured. The measured inductance was in reasonable agreement with the analytical prediction, though large variations in material permeability are expected from the mechanical processing of the ferrite. Some of the experimental transformers were observed to satisfy the Ethernet inductance requirement.

Modeling Walking with an Inverted Pendulum Not Constrained to the Sagittal Plane. Numerical Simulations and Asymptotic Expansions

Inverted pendulum models are commonly used to study the bio-mechanics of biped walkers. In its simplest form, the inverted pendulum consists of a point mass attached to two straight mass-less legs. Most works constrain the motion of the mass to the sagittal plane, i.e. the plane perpendicular to the ground that contains the direction toward the biped is walking. In this article, we remove this constrain to study the oscillations, the mass experiences in the direction perpendicular to the sagittal plane as the biped walks. While small, these lateral oscillations are unavoidable and of importance in the understanding of balance and stability of walkers, as well as walkers induced oscillations in pedestrian bridges.