Back Bending Research Articles

Effect of operation table height on ease of mask ventilation, laryngeal view, and endotracheal intubation success.

Optimal patient positioning and operating table height are essential for an ergonomic posture of an anesthesiologist in which there is minimal or no strain on thewrist during mask ventilation. It also avoids flexion of the neck, lower back, and knee bending at the time of laryngoscopy and intubation. One hundred eighty patients were randomly allocated to three groups based on different table heights. The height of the table is kept at the mid-sternum level of an anesthesiologist in group 1, at the xiphoid process in group 2, and at the level of umbilicus in group 3. Laryngoscopic view with or without postural changes (exertion at wrist joint, flexion of the neck, lower back, or knee bending) was graded as per Cormack Lehane's (CL) grading. The degree of discomfort experienced by the anesthesiologist during mask ventilation or tracheal intubation was graded subjectively (1 = no discomfort, 2 = mild discomfort, 3 = moderate discomfort, and 4 = severe discomfort) at different table heights. Postural changes required to obtain the best glottic view and quality of endotracheal (ET) intubation (intubation time and attempts required) were also noted. For analysis, quantitative variables were expressed as mean ± SD and compared using unpaired t or analysis of variance test. Qualitative variables were expressed as frequencies/percentages and compared using the Chi-square test. Results with P value <0.05 were considered significant statistically. Moderate discomfort (strain at wrist joint) during bag-mask ventilation was experienced by the anesthesiologist in a maximum number of patients in group 1 (81.7%). Significant improvement was seen in CL grade after the use of postural modifications in groups 1 and 2 (P value ≤0.05). Greater postural modifications were required during ET intubation at lower table heights (group 3). It is advisable to adopt higher table positioning in relation to anesthesiologist performing the laryngoscopy for smooth and single-attempt ET intubation since the best laryngoscopic view and intubation with minimal postural modifications was seen at higher table heights (at the mid-sternum level of an anesthesiologist).

Peculiarities of Rotational Bands in Heavy and Superheavy Nuclei: Description of Yrast-Band States in 248Cm

A further development of the expanded microscopic version of the IBM is presented by considering two-quasiparticle phonons with multipolarity up to J = 14+J. The developed theoretical scheme is applied to describe the properties of the yrast-band states in 248Cm up to spin 34+. This heavy transactinide nucleus is the only nucleus in this mass region where the values of B(E2) up to spin I = 28+ are measured. That is why it is considered foremost, because this information allows testing the presented theoretical scheme based on a larger volume of experimental data. The region of transactinide nuclei differs from lighter ones by the absence of the effect of the back bending in the moment of inertia dependence on the square of the rotation frequency up to the spin I = 28+. This article is intended in particular to find out the reason for this effect. Peculiar properties of the rotational bands in heavy and superheavy nuclei are discussed.

Describe of Nuclear Structure for Germanium (_32^66)Ge_34) Nucleus under frame (IBM-1, GVMI and VMI) Models

In this paper, the interacting bosons model-1 (IBM-1), a variable moment of inertia (VMI) and generalized moment of inertia (GVMI) models were used to calculate the energy levels of the positive parity and its gamma transitions as a function of the angular momentum of even-even (_32^66Ge_34) nucleus. To determine the dynamic symmetry of this nucleus, the ratios of the energy levels (E_4^+)⁄(E_2^+ ), (E_6^+)⁄(E_2^+), and (E_8^+)⁄(E_2^+) were evaluated and compared with experimental energy values and the ideal scheme of the three dynamic symmetries SU(5), SU(3), and O(6). The current study showed that the dynamic symmetry of this nucleus is determined to be O(6) - SU(5). The intersection of the energy band and the phenomenon of back bending were also studied using the (VMI) and (GVMI) models. These consequences were compared with the experimental results, and the results obtained have been in good agreement.

Oxygen Consumption and Heart Rate Responses in Different Vinyasa Yoga Sequences.

Yoga is widely practiced for its numerous health benefits, and it can also increase energy expenditure. Vinyasa yoga, a system of hatha yoga, meets criteria for moderate-intensity physical activity. It is unclear whether the individual sequences produce different oxygen consumption (VO2) and heart rate responses. The purpose of the present study was therefore to evaluate potential differences in VO2 and heart rate responses across sequences of a 60-minute vinyasa session. Participants included 40 healthy male (n = 20) and female (n = 20) adults (age 30.9 ± 8.8 y) with self-reported yoga experience. The sequence implemented was based on Baron Baptiste's Journey into Power sequence. This vinyasa yoga practice included several sequences: integration, sun salutation, crescent lunges, balancing, standing, back bending, and restorative. VO2 (mL/kg/min) was measured by portable indirect calorimetry and expressed as metabolic equivalents (MET). Heart rate was measured using a Polar HR monitor and presented as a percentage of age-predicted maximal heart rate (APMHR). METs and APMHR differed significantly across sequences (each p < 0.001). METs for the integration, sun-salutation, crescent-lunges, balancing, standing, back-bending, and restorative sequences were significantly different from one another (p < 0.001); balancing and back-bending sequences, however, were similar. During the integration and restorative sequences, APMHR was similar (p = 1.00) and significantly lower compared to sun-salutation, crescent-lunge, balancing, standing, and back-bending sequences (each p < 0.001). METs and APMHR differed significantly across sequences of a vinyasa yoga practice. These data could inform an individualized yoga series based on current fitness levels to maintain or improve cardiorespiratory fitness.

Validation of a Sensor-Based Dynamic Ski Deflection Measurement in the Lab and Proof-of-Concept Field Investigation.

Introduction: Ski deflection is a performance-relevant factor in alpine skiing and the segmental and temporal curvature characteristics (m−1) along the ski have lately received particular attention. Recently, we introduced a PyzoFlex® ski deflection measurement prototype that demonstrated high reliability and validity in a quasi-static setting. The aim of the present work is to test the performance of an enhanced version of the prototype in a dynamic setting both in a skiing-like bending simulation as well as in a field proof-of-concept measurement. Material and methods: A total of twelve sensor foils were implemented on the upper surface of the ski. The ski sensors were calibrated with an empirical curvature model and then deformed on a programmable bending robot with the following program: 20 times at three different deformation velocities (vslow, vmedium, vfast) with (1) central bending, (2) front bending, (3) back bending, (4) edging left, and (5) edging right. For reliability assessment, pairs of bending cycles (cycle 1 vs. cycle 10 and cycle 10 vs. cycle 20) at vslow, vmedium, and vfast and between pairs of velocity (vslow vs. vmedium and vslow vs. vfast) were evaluated by calculating the change in the mean (CIM), coefficient of variation (CV) and intraclass correlation coefficient (ICC 3.1) with a 95% confidence interval. For validity assessment, the calculated segment-wise mean signals were compared with the values that were determined by 36 infrared markers that were attached to the ski using an optoelectrical measuring system (Qualisys). Results: High reliability was found for pairs of bending cycles (CIM −0.69–0.24%, max CV 0.28%, ICC 3.1 > 0.999) and pairs of velocities (max CIM = 3.03%, max CV = 3.05%, ICC 3.1 = 0.997). The criterion validity based on the Pearson correlation coefficient was r = 0.98. The accuracy (systematic bias) and precision (standard deviation), were −0.003 m−1 and 0.047 m−1, respectively. Conclusions: The proof-of-concept field measurement has shown that the prototype is stable, robust, and waterproof and provides characteristic curvature progressions with plausible values. Combined with the high laboratory-based reliability and validity of the PyzoFlex® prototype, this is a potential candidate for smart ski equipment.

Influence of Load Knowledge on Biomechanics of Asymmetric Lifting.

Background: Load knowledge has been identified as a factor affecting the risk of low back pain (LBP) during symmetric lifting. However, the effects of load knowledge in asymmetric lifting tasks have not been reported yet. The purpose of this study was to investigate the load knowledge influence on lifting biomechanics in asymmetric lifting tasks; Methods: Twenty-four male adults were recruited to complete a psychophysical lifting capacity test and a simulated asymmetric lifting task. The lifting task was set with load knowledge of ‘no knowledge’ (NK), ‘weight known’ (WK), ‘fragile material known’ (FK), and ‘weight and fragile material known’ (WFK) for different lifting load weights. Trunk kinematics and kinetics were collected and analyzed; Results: When fragility information was presented, trunk sagittal flexion acceleration, lateral flexion velocity and acceleration, and average lateral bending moment were significantly lowered at the deposit phase. Lifting a high load weight was found to significantly increase low back sagittal bending moment at the lifting phase and low back moments of all three dimensions at the deposit phase; Conclusions: The decrease of trunk kinematic load suggests that providing material fragility information to workers in asymmetric lifting tasks would be effective in reducing their risk of LBP.

A Lower-Back Exoskeleton With a Four-Bar Linkage Structure for Providing Extensor Moment and Lumbar Traction Force

Lower back pain and related injuries are prevalent and serious problems in various industries, and high compression force to the lumbosacral (L5/S1) region has been known as one of the key factors. Previous research on passive lower back exoskeletons focused on reducing lumbar muscle activation by providing an extensor moment. Additionally, lumbar traction forces can reduce the compression force, and is a common treatment method for lower back pain in clinics. In this paper, we propose a novel passive lower back exoskeleton that provides both extensor moment and lumbar traction force. The working principle of the exoskeleton, extending the coil springs during lumbar flexion, and its design criteria regarding the amount of each force element were provided. The kinematic model explained its operation, and the dynamic simulation estimated its performance and validated its satisfaction with the design criteria. The biomechanical model provided a brief insight into the expected exoskeleton's effect on the reduced lower back compression force. Ten subjects performed static holding and dynamic lifting tasks, and the generated force elements in two directions, parallel and perpendicular to the trunk, were evaluated using a force sensor and electromyography sensors, respectively. The experiment demonstrated a pulling force opposite to the direction of intradiscal pressure and reduced erector spinae activation. This implies the effect of wearing the exoskeleton to decrease the intervertebral pressure during static back bending or heavy lifting tasks.

The Physiological Aspect of Backbending Asana's

The Hathyogic Asanas are the preparatory limbs for spiritual awakening, but they are also an essential health science. True, practicing Asanas takes more time and work for a long-term and beneficial effect, but it is a very potent and effective therapy.&#x0D; The numerous organs and systems in the physical body each have their own function to fulfill, but there should be total coordination between them, which is achieved via the practice of Hathyogic Asanas. Asanas serve to control psychosomatic disorders by improving physiological efficiency, anatomic balance, and mental poise and equilibrium in the body.&#x0D; It was employed by yogis and rishis in ancient times for the relief and elimination of all kinds of ailments and faults, and it was only recently recognized that asana are more powerful and effective techniques of managing the entire body. Hathyogic asana has been the subject of scientific research and investigations for the past three decades, proving that it offers biological benefits. In this study we have used a literature survey method on the basis of different yogic texts to find out the actual effect of back bending asana.

Sex difference in tDCS current mediated by changes in cortical anatomy: A study across young, middle and older adults

IntroductionThe observed variability in the effects of transcranial direct current stimulation (tDCS) is influenced by the amount of current reaching the targeted region-of-interest (ROI). Age and sex might affect current density at target ROI due to their impact on cortical anatomy. The present tDCS simulation study investigates the effects of cortical anatomical parameters (volumes, dimension, and torque) on simulated tDCS current density in healthy young, middle-aged, and older males and females. MethodologyIndividualized head models from 240 subjects (120 males, 18–87 years of age) were used to identify the estimated current density (2 mA current intensity, 25 cm2 electrode) from two simulated tDCS montages (CP5_CZ and F3_FP2) targeting the inferior parietal lobule (IPL) and middle frontal gyrus (MFG), respectively. Cortical parameters including segmented brain volumes (cerebrospinal fluid [CSF], grey and white matter), cerebral-dimensions (length/width &length/height) and brain-torque (front and back shift, petalia, and bending) were measured using the magnetic resonance images (MRIs) from each subject. The present study estimated sex differences in current density at these target ROIs mediated by these cortical parameters within each age group. ResultsFor both tDCS montages, females in the older age group received higher current density than their male counterparts at the target ROIs. No sex differences were observed in the middle-aged group. Males in the younger age group had a higher current density than females, only for the parietal montage. Across all age groups, CSF, and grey matter volumes significantly predicted the current intensity estimated at the target sites. In the older age group only, brain-torque was a significant mediator of the sex difference. ConclusionsOur findings demonstrate the presence of sex differences in the simulated tDCS current density, however this pattern differed across age groups and stimulation locations. Future studies should consider influence of age and sex on individual cortical anatomy and tailor tDCS stimulation parameters accordingly.

Investigation of wet etching solutions and method for thicker stand alone type of mesa structures of Bi2212 single crystals

In order to develop terahertz emitting devices based on high temperature superconductor Bi2212, we explored a simple and easy fabrication process of the stand alone type of mesa structures (SAMs) by using a wet etching method. We underscored a fact that a thicker mesa structure up to about 10 μm can be made by finding an appropriate etching process comparing four different solutions in the wet etching processes. In addition, we have also improved a method to produce free standing SAM chips which are not fixed on any substrates by glues. We measured the characteristics of the device fabricated using this wet etching method and observed clear emission from a chip with the dimensions of 170 × 170 × 8.3 μm3 without the local heating signature of back bending behavior in the current–voltage characteristics. This mesa chip is several times thicker than those used previously. Thus, the method shown here enables us to make many thicker SAMs at a time and would be useful to improve the emission power of superconducting terahertz emitters.

Calculation of Nuclear Properties for 56–62Fe Isotopes in the Model Space (HO) Using NuShellX@MSU Code

The nuclear shell model has been applied to calculate the yrast energy levels, quadrupole transition probability (BE2), deformation parameter B2, rotational energy (hw), and inertia moment (20/h2) for the ground state band. The NuShellX@MSU code has been used to determine the nuclear properties of 56−62Fe isotopes, by using the harmonic oscillator (HO) model space for P (1f7/2), N (2p3/2), N (1f5/2), and N (2p1/2) orbits and (HO) interaction. The results are in good agreement with the available experimental data on the above nuclear properties and all nuclei under study. In addition, the back bending phenomenon has been explained by the calculations, and it has been very clear in 58,60,62Fe nuclei. It has also been confirmed and determined the most spins and parities of energy levels. In these calculations, new values have been theoretically determined for the most nuclear properties which were previously experimentally unknown.

Study of Nuclear Radius and Back bending phenomenon of 20-30Mg Isotopes in sdpn Model Space

In present work, many parameters have been computed using NuShellX@ MSU code for ground state bands of 20-30Mg isotopes. These parameters were root mean square of nuclear radius, major and minor of ellipsoid axises (a and b), as well as to the different between them(ΔR) deformation parameters (β2, δ), intrinsic quadrupole moment(Q0) and back bending phenomenon. Model space(sdpn) of (0d3/2,0d5/2 and 1s1/2) for protons and neutrons orbits and cwhcdpn interaction have been used to calculate above parameters. Effective charge of Bohr - Mottelson model has been used in this work. The results showed an brilliant agree with the obtainable investigational results all isotopes in this study. Also, the back bending phenomenon was well evident in our results for all isotopes used under study. In these calculations, new values have been theoretically designated for most parameters which were previously unknown in experimental information.

Body Caudal Undulation Measured by Soft Sensors and Emulated by Soft Artificial Muscles.

We propose the use of bio-inspired robotics equipped with soft sensor technologies to gain a better understanding of the mechanics and control of animal movement. Soft robotic systems can be used to generate new hypotheses and uncover fundamental principles underlying animal locomotion and sensory capabilities, which could subsequently be validated using living organisms. Physical models increasingly include lateral body movements, notably back and tail bending, which are necessary for horizontal plane undulation in model systems ranging from fish to amphibians and reptiles. We present a comparative study of the use of physical modeling in conjunction with soft robotics and integrated soft and hyperelastic sensors to monitor local pressures, enabling local feedback control, and discuss issues related to understanding the mechanics and control of undulatory locomotion. A parallel approach combining live animal data with biorobotic physical modeling promises to be beneficial for gaining a better understanding of systems in motion.

Axial shape asymmetry and high-spin states in nuclei with Z=100 suggested by the projected total energy surface approach

The axial-shape asymmetry of yrast states in $^{246--256}\mathrm{Fm}$ is studied by performing the projected total-energy surface (PTES) calculations, which consider the beyond-mean-field effects associated with the restoration of rotational symmetry and shape variation at the same time. The results show a large elongation deformation but also a considerable large triaxiality for their ground and high spin states, the triaxial deformation $\ensuremath{\gamma}\ensuremath{\approx}{11}^{\ensuremath{\circ}}$ in average. In comparison, the TRS calculations have also been performed for these nuclei, and the results show a well-established axial quadrupole shape in their ground states. The presence of the significant triaxial deformation can be attributed to the beyond-mean-field effects generated by the angular-momentum projection. The axial asymmetric shape for the yrast states of nuclei with $Z=100$, suggested by the present variation after projection (VAP) calculations, indicates that the triaxial degree of freedom may also play a significant role in other transfermium and even superheavy nuclei. The present PTES calculations have well reproduced the available experimental energies of the ground-band states and predict the rest yrast states up to spin 30 in each nucleus. The calculated yrast bands of $^{246--256}\mathrm{Fm}$ present the back bending phenomenon at about the state ${18}^{+}$, caused by the alignment excitations of the two quasiparticle neutrons of $\ensuremath{\nu}{j}_{15/2}[743]7/2$ or of $\ensuremath{\nu}{h}_{11/2}[761]1/2$. It is worth confirming the predicted band structures by the future spectroscopic experiments in the transfermium nuclei for the study of the single-particle structure in the superheavy mass region.

Correction to: Study of Back Bending in 157,158Er Isotopes by Using Electromagnetic Reduced Transition Probabilities

Correction to: Study of Back Bending in 157,158Er Isotopes by Using Electromagnetic Reduced Transition Probabilities

Studying the nuclear structure of the () deformed nucleus by using (IBM-1) and (VAVM) Models

In this paper, the nuclear structure of the deformed even-even nucleus was studied using the first interacting boson model (IBM-1) to calculate the energy levels E(L) and the transitional energy (Eγ ). The energy bands, as well as the quadrupole moment (QL ) can be calculated to know the shape of the nucleus and the moment of inertia model, energy levels E(L), transitional energy (Eγ ) and the bands intersection. The current study showed that at dynamic symmetry SU (3), there is no effect of inertia moment on the shape of the rotational nuclei due to the absence of the phenomenon of back bending that belongs to this dynamic symmetry, through calculating the energy levels ratios found that nucleus belongs to the rotational dynamic symmetry SU (3). A comparison of the available practical results with the results calculated by (VAVM) and (IBM-1) showed that the (VAVM) model are better than the results calculated by (IBM-1).

Research on auxiliary bed - lifting device for the elderly

Although there are devices to assist the elderly to get out of bed in China, most of them are aimed at the disabled elderly or still need artificial assistance. For some old people with certain activity ability, there is no appropriate auxiliary equipment at present. Based on this background, the electric push rod and gear system are used to realize the back lifting, leg bending and auxiliary standing functions of the elderly when they get up and lie down. The matching design of connecting rod mechanism and gear mechanism is adopted to meet all the needs of the elderly when they get up and lie down with a simple mechanism.

Combined ergonomic exposures and development of musculoskeletal pain in the general working population: A prospective cohort study.

Objective:This study aimed to investigate the importance of combined ergonomic exposures at work for the development of musculoskeletal pain.Methods:Through four rounds (2012–2018) of the Work Environment and Health in Denmark Study, 18 905 employees of the general working population replied to a baseline and 2-year follow-up questionnaire. First, a k-means cluster analysis of seven ergonomic factors (back bending, arm above shoulders, lifting etc., from ‘never’ to ‘almost all the time’) identified nine naturally occurring clusters. Second, using a weighted survey regression model controlling for age, gender, survey year, education, lifestyle, influence at work, and pain intensity at baseline, we estimated development of pain intensity (0–10) in the neck-shoulder and low-back in these clusters. The largest cluster served as reference to the other clusters and was characterized by low ergonomic exposures.Results:Clusters characterized by multiple combined ergonomic exposures for a relatively high percentage of the working time showed the largest increase in neck-shoulder as well as low-back pain intensity from baseline to follow-up. However, clusters characterized by high exposure to a few specific ergonomic factors also increased pain significantly, eg, standing/walking combined with lifting/carrying or twisted/bent back for the majority of the working time increased low-back pain, whereas repetitive arm movements for the majority of the working time with or without standing/walking increased neck-shoulder pain.Conclusion:Combined occupational ergonomic exposures play an important role in the development of musculoskeletal pain. Workplace preventive approaches should consider this in risk assessments and organization of the work.

Study of the nucleon-rich effect in 158Er and 185Os rare-earth nuclei using the projected shell model

In this paper, the structure evolution in 158Er and185Os isotopes is calculated using the projected shell model (PSM) framework. The yrast spectrum, nucleon-rich effects, back-bending phenomenon, and the ratio of reduced electromagnetic transition probabilities, B(M1)/B(E2), are calculated in the spins ranges 8+–22+ and 17/2+–45/2+ for the mentioned isotopes, respectively. In the yrast spectrum, band crossing of one, two, and three quasi-particle bands at spins around 12+ and 41/2+, which is a sign of nucleon alignments, is investigated and 27 additional nucleons are found to be the reasons for back bending at lower spins in 158Er than 185Os, which is coincident with two great drops in the B(M1)/B(E2) ratio plots.

THE EFFECT OF TRANSFER DISTANCE TO LOWER BACK TWISTING AND BENDING PATTERNS IN MANUAL TRANSFER TASK

Manual material handling (MMH) activities utilize human’s effort with minimal aid from mechanical devices. MMH is typically associated with poor lower back posture which can lead to lower back injury. The likelihood to develop musculoskeletal disorders (MSDs) increases when poor working posture exist in combination with repetition and/or forceful exertion. In manual transfer activity, the distance between lifting origin and destination could affect workers’ exposure on poor lower back working posture. An experimental study was conducted to investigate the effect of transfer distance to lower back twisting and bending pattern in manual transfer activity. Positional body joints data of 26 male subjects were captured using the combination of motion capture (MOCAP) system with MVN studio software. Calculated data were plotted against time to track subjects’ lower back twisting and bending behavior. In general, longer the transfer distance would result in smaller twisting angle but higher bending angle. Statistical analysis in this study suggests 0.75m to 1.00m as the optimum transfer distance to balance lower back twisting and bending exposure on workers. This study is envisioned to provide insights for practitioners to consider space requirements for MMH activity to minimize lower back twisting and bending, and consequently the development of MSDs.