Single Foot Research Articles

The Mathematical Modeling and Dynamic Trot Gait Simulation on the Single Leg Hydraulic Drive System of the Quadruped Robot

In this paper, the single leg hydraulic drive system of the quadruped robot is taken as the research object. Then the nonlinear mathematical model of the hydraulic system is built. According to the real mechanical structure parameters of the single leg, the relationship between position control characteristics of the system and variation of single leg trajectory is investigated. Besides, the tracing accuracy of single leg foot displacement in one trot gait condition is analyzed through combination of kinematics solution and simulation analysis. In conclusion, the research indicates that the nonlinear mathematical model can be used to analyze the position control performance of the single leg hydraulic drive system. This research provides a basic foundation for further research of control method.

The Effects of Acute Cupping Therapy on Balance, Flexibility and Muscular Power

In the recent Rio Olympics, spectators witnessed round circles across the upper back of swimmer Michael Phelps and others. These circles were as the result of cupping therapy (CUP) received prior to competitive performances and drew widespread publicity, despite little scientific evidence to support the practice. PURPOSE: To evaluate the impact of acute CUP on muscular power, balance and flexibility, 12 subjects (age 21.4± 1.2, ht. 167.6 ± 8.4 cm, and body mass 71.6 ± 18.2 kg, 7♀) volunteered. METHODS: Familiarization trials preceded CUP by 48 hrs and included all of the following tests: single foot balance with a sway index (SI) on the Biodex Balance System with unilateral trials for 20 seconds and 10 sec recovery repeated twice. Flexibility included two measures of unilateral passive hip range of motion by goniometer with the subject in the prone (hip extension [HE]) and supine (straight leg raise test of hamstring [HF]) positions. Hamstring/quadriceps unilateral muscle power (MP) testing was conducted with a Biodex Isokinetic dynamometer (Watts = W) including five repetitions @ 60o/sec warm-up and 10 maximal repetitions at 120o/sec for the trial. Assessments were conducted within 15 minutes of CUP (PreC), as well as within 15 minutes post (Post15) and 60 minutes post (Post 60) CUP. CUP required the application of 6 plastic cups applied at -14 PSI bilaterally for 10 minutes at 30 mm lateral of the vertical midline of the posterior thigh above the hamstring muscle group. RESULTS: Statistical analysis by ANOVA (p<.05) with repeated measures revealed no significant differences among matched variables including: MP(W): 64, 62, & 59.4, and 63.8, 58.7, & 56.3; HED(degrees): 13.3, 13.4 & 13.8, and 12.3, 13.2, & 12; HF(degrees): 67.4, 65.8, & 63.8, and 66.5, 63.8, & 64.3 and SI: .94, .83, & .95 and 1.17, .96, & .76, for CUP and No CUP treatments, respectively. CONCLUSION: A single application of CUP did not yield changes in muscular power, flexibility or balance when assessed within 60 minutes of the treatment. These data fail to support the practice of cupping for improved strength, flexibility or balance.

The effects of 10-week core strength training on the body balance in the middle-aged men

To observe the effects of core strength training on the body balance of middle-aged men, which could provide evidence for improving the body balance and reducing the risk of falls in the middle-aged men. Sixteen 50~60 years old men were randomly divided into experimental group (core strength training, n=8) and control group(n=8). Intermittent core strength trainings were used for dynamic and static training, push-pull training and unarmed lower limb strength training by suspension ropes and yoga mat. The time for training was 50~60 min/day, 4~5 times/week for a total of 10 weeks. The men in control group remained their original living habits. We measured the ability of body static balance and dynamic balance before and after the core strength training. ① Compared with before exercise training, both closed single foot standing time and the body dynamic balance were increased significantly in the experimental group after exercise training(P<0.01)(10.63±1.69 s vs 9.00±2.27 s; 77.38±10.94 vs 89.50±5.53). ② Compared with before exercise training, star excursion balance test(SEBT) values were significantly increased in the left leg(the right leg support) in eight directions and the right leg(the left leg support)in six directions (P<0.01). Ten-week core strength training can significantly increase the body static and dynamic balance in the middle-aged men.

Open Repair of Acute Achilles Tendon Ruptures: Is the Incidence of Clinically Significant Wound Complications Overestimated?

Background: Conflicting evidence exists regarding the optimal management of acute Achilles tendon ruptures. Operative repair is thought to afford patients a lower risk of rerupture, albeit at a higher overall risk of wound complications. Methods: A retrospective chart review of 369 consecutive patients undergoing open repair of acute Achilles tendon ruptures performed by a single foot and ankle fellowship-trained orthopedic surgeon was undertaken. Healing was classified as no complications, complications without prolonging treatment, complications requiring prolonged local treatment, and complications requiring operative intervention. A statistical analysis comparing the rates of complications in this cohort to that reported in the literature was conducted. Results: There were a total of 33 (8.94%) wound complications. Compared to the rates reported in the literature, no significant difference was detected ( P = .3943; CI 6.24-12.33). However, when the complications not requiring additional treatment or prolonged care were excluded, only 9 wound complications (2.44%) were identified—a significantly lower complication rate than that reported in the literature ( P &lt; .0001; CI 1.12-4.58). There were only 2 (0.54%) major complications requiring operative intervention, also a significantly lower rate than in the literature ( P &lt; .0001; CI 0.067-1.94). Conclusion: In the past, wound-healing complications have been cited as a concern when treating patients operatively. We found that when solely looking at healing complications prolonging the patients’ overall recovery, a significantly lower rate of complications existed compared to that reported in the literature. Level of Evidence: Level IV.

All-polyethylene tibial components in distal femur limb-salvage surgery: a finite element analysis based on promising clinical outcomes

BackgroundWhether all-polyethylene tibial (APT) components are beneficial to patients who received distal femur limb-salvage surgery lacks high-quality clinical follow-up and mechanical evidence. This study aimed to investigate the biomechanics of the distal femur reconstructed with APT tumor knee prostheses using finite element (FE) analysis based on our previous, promising clinical outcome.MethodsThree-dimensional FE models that use APT and metal-backed tibial (MBT) prostheses to reconstruct distal femoral bone defects were developed and input into the Abaqus FEA software version 6.10.1. Mesh refinement tests and gait simulation with a single foot both in the upright and 15°-flexion positions with mechanical loading were conducted. Stress distribution analysis was compared between APT and MBT at the two static positions.ResultsFor both prosthesis types, the stress was concentrated on the junction of the stem and shaft, and the maximum stress in the femoral axis base was more than 100 Mpa. The stress on the tibial surface was relatively distributed, which was 1–19 MPa. The stress on the tibial bone-cement layer of the APT prosthesis was approximately 20 times higher than that on the MBT prosthesis in the same region. The stress on the proximal tibial cancellous bone and cortical bone of the APT prosthesis was 3–5 times greater than that of the MBT prosthesis, and it was more distributed.ConclusionsAlthough the stress of bone-cement around the APT component is relatively high, the stress was better distributed at the polyethylene-cement-bone interface in APT than in MBT prosthesis, which effectively protects the proximal tibia in distal femur tumor knee prosthesis replacement. These results should be considered when selecting the appropriate tibial component for a patient, especially under the foreseeable conditions of osteoporosis.

Effect of Psychomotor Program for Material Experience on the Coordination of Children with ADHD

Background/Objectives: The purpose of this study is to analyze the effects of psychomotor program for material experience on the coordination of children with ADHD. Methods/Statistical analysis: The subjects of this study were divided into two groups: an experimental group of 8 children and a control group of 8 children, who are all enrolled in the D Children's Development Center and the K Children's Development Center in Seoul. The study was conducted for 12 weeks, twice per week, 60 minutes in for one session. Coordination tests were conducted in the before- and after-session, respectively, for both groups. As a coordination test instrument, the KTK, which was designed and standardized by Kiphard and Schilling in 1974, was used. SPSS 22.0 was used to process the data, and two-way ANOVA was conducted to compare the data between groups and times. The hypothesis testing is fixed to significance level of p<.05. Findings: The results of the analysis were as follows: First, rear balancing MQ1 showed a statistically meaningful difference not only in the interaction effect between time and group, but also in the main effect of time and group. Second, single foot jumping MQ2 showed a statistically meaningful difference not only in the interaction effect between time and group, but also in the main effect of time and group. Third, left and right jumping MQ3 showed a statistically meaningful difference not only in the interaction effect between time and group, but also in the main effect of time and group. Fourth, lateral movement MQ4 showed a statistically meaningful difference not only in the interaction effect between time and group, but also in the main effect of time and group. Fifth, KTK MQT showed a statistically meaningful difference not only in the interaction effect between time and group, but also in the main effect of time and group. Improvements/Applications: The material experience-based psychomotor program needs to be verified by approaching various subjects as well as ADHD children.

Simple peptide coacervates adapted for rapid pressure-sensitive wet adhesion.

We report here that a dense liquid formed by spontaneous condensation, also known as simple coacervation, of a single mussel foot protein-3S-mimicking peptide exhibits properties critical for underwater adhesion. A structurally homogeneous coacervate is deposited on underwater surfaces as micrometer-thick layers, and, after compression, displays orders of magnitude higher underwater adhesion at 2 N m-1 than that reported from thin films of the most adhesive mussel-foot-derived peptides or their synthetic mimics. The increase in adhesion efficiency does not require nor rely on post-deposition curing or chemical processing, but rather represents an intrinsic physical property of the single-component coacervate. Its wet adhesive and rheological properties correlate with significant dehydration, tight peptide packing and restriction in peptide mobility. We suggest that such dense coacervate liquids represent an essential adaptation for the initial priming stages of mussel adhesive deposition, and provide a hitherto untapped design principle for synthetic underwater adhesives.

Association of Abnormal Metatarsal Parabola With Second Metatarsophalangeal Joint Plantar Plate Pathology.

Plantar plate pathology is common, yet it is unclear whether, and to what extent, the length of the second metatarsal contributes to this problem. We conducted a retrospective case-control (1:2) study to examine radiographic risk factors for plantar plate tears. One hundred patients (age 55.7 ± 12.3 years) with plantar plate injuries and 200 healthy controls (age 56.3 ± 11.3 years) were included. Cases were defined as patients with nonacute, isolated, plantar plate pathology of the second metatarsophalangeal joint confirmed by intraoperative inspection at a single foot and ankle specialty practice from June 1, 2007, to January 31, 2014. Patients presenting for pain outside of the forefoot served as the control group. Controls were matched on age (±2 years), gender, and year of presentation. Weight-bearing foot x-rays were assessed for several predetermined angular relationships by a single rater. Conditional logistic regression was used to identify risk factors for plantar plate injury. A long second metatarsal, defined as a metatarsal protrusion index less than -4 mm, was the only significant risk factor for plantar plate pathology in both the univariate and multivariable analyses (multivariate odds ratio 2.5 [95% confidence interval 1.8 to 3.3], P = .002). We found that a long second metatarsal was a risk factor for developing second metatarsophalangeal joint plantar plate tears. This knowledge may aid foot and ankle surgeons when contemplating the need for second metatarsal shortening osteotomies (eg, Weil osteotomy) during plantar plate surgery and when deciding on the amount of shortening for second metatarsal osteotomies. Level III, retrospective comparative study.

Visual processing is biased in peripersonal foot space

Objects in peripersonal space are of great importance for interaction with the sensory world. A variety of research exploring sensory processing in peripersonal space has produced extensive evidence for altered vision near the hands. However, visual representations of the peripersonal space surrounding the feet remain unexplored. In a set of four experiments, we investigated whether observers experience biases in visual processing for objects near the feet that mirror the alterations associated with near-hand space. Participants performed attentional-cueing tasks in which they detected targets appearing (1) near or far from a single visible foot, (2) near one of two visible feet, (3) near or far from a nonfoot visual anchor, or (4) near or far from an occluded foot. We found a temporal cost associated with detecting targets appearing far from a visible foot, but no biases were associated with targets appearing near versus far from either a nonfoot visual anchor or an occluded foot. These results provide the first evidence suggesting that objects within stepping or kicking distance are processed differently from objects outside of peripersonal foot space.

Determination of the in situ mechanical behavior of ankle ligaments

The mechanical behavior of ankle ligaments at the structural level can be characterized by force–displacement curves in the physiologic phase up to the initiation of failure. However, these properties are difficult to characterize in vitro due to the experimental difficulties in replicating the complex geometry and non-uniformity of the loading state in situ. This study used a finite element parametric modeling approach to determine the in situ mechanical behavior of ankle ligaments at neutral foot position for a mid-sized adult foot from experimental derived bony kinematics. Nine major ankle ligaments were represented as a group of fibers, with the force–elongation behavior of each fiber element characterized by a zero-force region and a region of constant stiffness. The zero-force region, representing the initial tension or slackness of the whole ligament and the progressive fiber uncrimping, was identified against a series of quasi-static experiments of single foot motion using simultaneous optimization. A range of 0.33–3.84mm of the zero-force region was obtained, accounting for a relative length of 6.7±3.9%. The posterior ligaments generally exhibit high-stiffness in the loading region. Following this, the ankle model implemented with in situ ligament behavior was evaluated in response to multiple loading conditions and proved capable of predicting the bony kinematics accurately in comparison to the cadaveric response. Overall, the parametric ligament modeling demonstrated the feasibility of linking the gross structural behavior and the underlying bone and ligament mechanics that generate them. Determination of the in situ mechanical properties of ankle ligaments provides a better understanding of the nonlinear nature of the ankle joint. Applications of this knowledge include functional ankle joint mechanics and injury biomechanics.

Outcomes Following Advanced Wound Care for Diabetic Foot Ulcers: A Canadian Study

Data concerning outcomes of Canadian patients with diabetic foot ulcers (DFUs) are limited. The objectives of this study were to evaluate the healing rates and identify the predictors of poor outcomes following advanced wound care in patients presenting with DFUs. We conducted retrospective cohort study of adult patients who had DFUs and were referred to a single Canadian advanced diabetic foot and wound care centre between January 1, 2010, and December 31, 2010. The primary outcome was the healing rate at 52 weeks. The generalized estimating equation model was used to identify potential risk factors associated with delayed healing of DFUs. Of the 40 patients for whom there were complete follow ups, 35 (87.5%) had healing of all DFUs by 52 weeks. Predictors of poor healing were the presence of chronic ulcers, ulcer sizes >1 cm2, peripheral vascular disease and multiple ulcers at first presentation. Of the patients, 7.1% required amputation, and 8.9% of patients receiving our treatment died before 52 weeks. At 52 weeks of follow up, 16 of 17 recurrent ulcers and 68 of 108 pre-existing ulcers had healed. Compared to the unadjusted healing rate of preexisting ulcers (63.0%), the unadjusted healing rate of recurrent ulcers (94.1%) was significantly higher (p=0.01). Our findings demonstrate that patients with DFUs in Canada who receive early and continued care from specialized, outpatient, advanced wound care centres experience significantly improved rates of healing of recurrent DFUs compared to pre-existing DFUs.

A Longitudinal Analysis of 25 Years of Foot &amp; Ankle Fellowship Training

Category: Other Introduction/Purpose: There is a growing demand for orthopaedic surgeons trained in management of foot and ankle conditions, yet there remains wide variation in the process of fellowship training and a dearth of outcomes assessment. The 2016- 2017 American Orthopaedic Foot &amp; Ankle Society (AOFAS) Fellowship Match consisted of 75 available positions—a 44% increase over that a decade prior. Of the 48 programs offering positions, 6 offer standardization and oversight by the Accreditation Council for Graduate Medical Education (ACGME). We aimed to assess the educational curriculum, research production and career paths of 25 years of graduates from the longest running ACGME accredited foot and ankle fellowship program in the United States. Methods: A database of graduates from a single foot and ankle fellowship program was utilized to identify practice types and locations as well as tabulate PubMed indexed articles authored by fellows while in the program. The educational curriculum corresponding to their training is described. Additionally, historical data from the AOFAS Match Program was evaluated for trends. Results: Between 2005-2015, there were 515 graduates of AOFAS sponsored foot &amp; ankle fellowship programs in the U.S. (Figure 1). Successful match rates for fellowship applicants ranged from 80-96% and program fill rates varied between 61-93%. Our fellowship program has graduated 50 fellows in the past 25 years of whom 37 (74%) practice in the U.S. and 13 (26%) practice abroad. When accounting for international, military and academic practitioners, 54% of our graduates entered practice types with a teaching component. Research articles for each fellow were examined and on average 1.9 PubMed indexed articles (range 0-12) were published by fellows during their tenure in the program. Graduates going into military, international and U.S. academic practices published 2.5, 2.8 and 3.7 articles during training, respectively. Conclusion: As technical and cognitive demands of foot and ankle surgeons increase, the need for optimized fellowship training has become paramount. Assessment of educational curriculum, research production and graduate practice type may help fellowships identify areas for improvement in order to meet program and trainee goals.

Economic Burden of Inpatient Admission of Ankle Fractures

Category: Trauma Introduction/Purpose: Ankle fractures are one of the most prevalent traumatic orthopaedic injuries. A large proportion of patients sustaining operative ankle fractures are admitted directly from the emergency room prior to surgical management. In our experience, however, many closed ankle injuries may be safely and effectively managed on an outpatient basis. This study aims to characterize the economic impact of routine inpatient admission of ankle fractures. Methods: A retrospective review of all closed ankle fracture surgery performed by a single foot and ankle fellowship trained surgeon at a tertiary level academic center in 2012 was conducted to identify patients requiring postoperative inpatient admission. The National Inpatient Sample was queried for operative lateral malleolus, bimalleolar, and trimalleolar ankle fractures in 2012 to evaluate national estimates and length of stay by age. The maximum allowable Medicare inpatient facility reimbursements and Medicare outpatient facility reimbursements were obtained from the Medicare Acute Inpatient Prospective Pricer and a Medicare Outpatient Pricer Code respectively. Private facility reimbursement rates were estimated at 139% of inpatient Medicare reimbursement and 280% of outpatient reimbursement as described in the literature. Surgeon and anesthesiologist fees were considered similar between both inpatient and outpatient groups. A unique stochastic decision tree model was derived from probabilities and associated costs and evaluated with modified Monte Carlo simulation. Results: Of 76 lateral malleolar, bimalleolar, and trimalleolar ankle fracture ORIF performed in 2012 by the senior author, 7 required admission due to polytrauma, medical comorbiditites or age. Of the 67 outpatient cases, all were discharged home the day of surgery. In the 2012 national cohort analyzed, 48,044 estimated inpatient admissions occurred postoperatively for closed ankle fractures. Median length of stay was three days, and associated with facility reimbursement ranging from $12,920 for Medicare lateral malleolus fractures to $18,613 for private reimbursement of trimalleolar fractures. Outpatient facility reimbursements per case were $4,125 for Medicare patients and $11,459 for private insurance patients. The national cohort’s inpatient admission accounted for $796,033,050 in reimbursements, while outpatient surgery would have been associated with $419,327,612 for treatment of these ankle fractures. Conclusion: Closed lateral malleolus, bimalleolar, and trimalleolar fractures may be safely and effectively treated as outpatient procedures. Routine perioperative admission for ankle fractures results in over $367 million of excess facility reimbursements annually in the US. Even if a conservative 25% necessary admission rate was assumed, routine inpatient admission of ankle fractures results in a $282 million dollar excess economic burden annually. While certain cases necessitate inpatient admission, with value based decision making becoming increasingly the responsibility of the orthopaedic surgeon, understanding cost implications of inpatient ankle fracture management may result in savings to the US healthcare system and patients individually.

Frontal Plane Rotation of the 1st Metatarsal in Relation to Arch Height

Category: Bunion Introduction/Purpose: There is a question as to the relationship of the effect of the arch height on the frontal plane rotation of the 1st metatarsal, and its impact on hallux valgus deformities. We attempt to evaluate this question and offer an answer for discussion. Methods: A series of patients who presented to a single orthopedic foot and ankle clinic with a compliant of hallux valgus deformity received a standardized 4 view standing radiograph series. These included the standard weight-bearing anterior- posterior, oblique, and lateral images. The fourth view was an axial sesamoid view to evaluate the frontal plane rotation. The first 50 patients that met our inclusion criteria were used. Inclusion criteria were skeletal maturity, non-traumatic issue, and primary bunion complaint with no complaint related to the arch. Any patients with prior surgery on the 1st metatarsal or arch structure were excluded. The radiographs where then evaluated by 2 fellowship trained foot and ankle specialist with predetermined radiographic parameters. The included measurements regarding the HAV deformity were IM angle, HAV angle, sesamoid position, DMAA, and axial sesamoid rotation. The measurements captured in relation to arch height included Meary’s angle, talonavicular coverage angle, medial cuneiform arch height, navicular height, and lateral talocalcaneal angle. Results: The collected information was then initially checked for inter-observer reliability and found to be consistent between the two observers. Collected values allowed the subjects to be placed into 3 initial categories labeled as planus, normal, and cavus based on the arch measurements. The imaging studies related to the HAV deformity was then classed initially as mild, moderate and severe. The HAV deformities were then further classified based on frontal plane rotation deformity and categorized as rotated, rotated and subluxed, subluxed, or no rotation. All of the individual group measurements were determined and quantified using the same radiographic software and uniform points of measurement. The information was then feed into algorithms that included direct comparisons as well as regression analysis of the defined subsets. Conclusion: After review of the data it was noted that there was no significant correlation between arch height measurements, HAV deformity and frontal plane rotation of the 1st metatarsal.

Model updating of real structures with ambient vibration data

It is important to develop reliable finite element models (FEMs) for real structures not only in the design-phase but also for the structural health monitoring and life-cycle management purposes. To do so, model updating is often carried out to minimise the discrepancies between FEMs and real structures. Among existing model updating approaches, sensitivity based model updating methods which can be either manual or automated, have proven to be very effective in the application of real structures and have been widely used on flexible bridge structures. However, very few studies were reported on buildings especially those with medium-rise characteristics which are often associated with complicated initial modelling and different degrees of parameter uncertainties. In addition, even-though a handful of studies has been done on manual model updating for bridge structures, not much research has taken into account the influence of external structural components on manual model updating process. To address these issues, two case studies with real structures are established in this research. One is conducted with a 10-story concrete building to demonstrate the importance of having sufficiently detailed initial FEMs in automated model updating of medium-rise buildings and effective use of boundary limits and parameter groups to maintain the physical relevance of the updated FEMs. Other is an investigation with a single span inflexible foot bridge to highlight the necessity to consider external structural components in manual model updating of inflexible structures. Both studies employ actual ambient vibration monitoring data obtained from the test structures for the model updating processes.

Nonlinear analysis of postural sway in subjects with below knee amputation during opened and closed eye conditions

ObjectiveThe aim of this study was to compare the structure of postural sway in healthy people and amputees with SACH foot (solid ankle cushion heel) and single axis foot during standing. MethodsTwenty healthy, 10 amputees with single axis foot, and 10 amputees with SACH foot participated in this study. The structure of postural sway of the subjects was evaluated using approximate entropy (ApEn). ResultsPeople with SACH foot prosthesis exhibit increased regularity in postural sway compared to healthy people and people with single axis foot. ConclusionAmputees who used single axis prosthesis achieved appropriate adaptation to their prosthesis device.

Improvement and miniaturization of a T-shaped linear piezoelectric actuator with single foot

ABSTRACTA miniaturized T-shaped linear piezoelectric actuator is designed. Modal analysis is developed to tune the resonance frequencies of the two vibration modes to be close; and the vibration trajectories of particles on the driving surface are investigated by transient analysis. The no-load speed of the prototype is 1127 mm/s, the maximum output thrust force is 41 N, and the maximum output power is 9.1 W. The power density of the prototype is 28.09 W/kg, which is nearly six times that of the previous design. This work provides new ideas for the optimal design of piezoelectric actuator using longitudinal vibrations.

Bizarre snail that swims like a flying insect

Snails usually lumber along on their single fleshy foot, but not sea butterflies (Limacina helicina). These tiny marine molluscs gently flit around their Arctic water homes propelled by fleshy wings that protrude out of the shell opening. But little was known about how they move through water. ‘Most zooplankton swim with a drag-based paddling technique,’ explains David Murphy from the Georgia Institute of Technology, USA, and even though one of Murphy's thesis advisors – Jeannette Yen – had filmed one of the enigmatic snails swimming while it was attached to a wire in 2003, it had not been possible to observe how fluid flowed around the animals to explain how they move. So, when Murphy built a new 3D system to visualise fluid movements around minute animals, Yen and Don Webster were keen to test more sea butterflies as they swam freely to discover more about their exotic mode of propulsion.However, working with the delicate animals in land-locked Atlanta posed a unique set of challenges. Murphy explains that sea butterflies are scarce at the best of times, and that transporting the fragile gelatinous creatures across the continent from their ocean home was tricky. ‘You have to ship them overnight in an insulated cooler to keep them cold and if the water is too dirty, particles will stick to them, so the water has to be very clean’, he says. Yen then devised a cunning V-shaped structure at the bottom of the tank to ensure that the freely swimming snails repeatedly ascended through the middle portion of the tank – where four high-speed cameras were focused to capture every detail of the wings’ movements. Even then, Murphy admits that it was a miracle that they were able to collect any data, and he recalls that the team only had a few short hours to film the molluscs, explaining that they could only be sure that the swimming conditions were ideal then. However, by the end of the afternoon the snails had serendipitously crossed the path of the cameras on four occasions. ‘In this sort of free-swimming experiment, it's normal to take 30 passes to get three usable ones, but we got really lucky! The animals even cooperated by swimming in different orientations, so we could see different perspectives’, chuckles Murphy, who then began visualising the snails' wing beats and the fluid movements around their bodies with Deepak Adhikari.After months of painstaking analysis – interrupted by Murphy's relocation from Georgia to Johns Hopkins University in Baltimore, Maryland – the team was astonished when they realised that the snails were swimming just like fruit flies fly. ‘I said to myself, “Its wing stroke is just like what an insect is doing”’, recalls Murphy, describing the snails’ characteristic figure-of-eight wing beat that was only apparent after he took account of the molluscs’ extraordinary bobbing motion. And when he investigated how water flowed around the snails’ wings, he was impressed to see that the molluscs generated the same low-pressure system that produces lift in flying fruit flies. Murphy explains that the snails (and fruit flies) clap their wings together at the top of a wing beat before peeling them apart, sucking fluid into the V-shaped gap between the wings to create low-pressure vortices at the wing tips that generate lift. He says, ‘No one has actually been able to measure the flow around an insect doing this while it is flying, and so that was kind of the holy grail of this area of research’. And he adds, ‘It really surprised me that sea butterflies turned out to be honorary insects’.

Effect of Foot Reflexology as an Add-on Intervention on Pain Among Women Having Undergone Mastectomy

A single group quasi-experimental study was conducted among 40 women on the flrst day after they underwent mastectomy. Subjects were selected by convenience sampling technique. A single sessionfoot reflexology was administered among post-mastectomy women. Pain was assessed at baseline, post-test I (immediately after foot reflexology) and post-test II (30 minutes after foot reflexology). The findings revealed that there was a statistically significant difference between the pain scores at baseline and both the post-tests (t (39) = 2.9, p <0.05 and t ,(39)= - 4.418, p < 0.05). A statistically significant reduction in physiologic parameters was also observed from the baseline (systolic BP at post-test I (t(39) = 2.470, p < 0.05).

Infectious lameness among migratory sheep and goats in north-west India, with particular focus on anaerobes.

Various bacterial species, particularly Dichelobacter nodosus, Fusobacterium necrophorum, Trueperella pyogenes (previously Arcanobacterium pyogenes) and Treponema spp., have been implicated in infectious conditions manifesting in lameness in sheep and goat populations. The current study reports the causes of infectious lameness in the north-western Himalayan region, particularly Himachal Pradesh (HP), where no such study has been conducted in the past. Among a total surveyed population of 27,586 animals, comprised of 15,006 sheep and 12,580 goats, 216 samples were collected from foot lesions. A total of 6.48% (14/216) samples were positive for D. nodosus, 20.83% (45/216) for F. necrophorum and 20.37% (44/216) for T pyogenes. In three instances, all of the three aforementioned bacteria were present in a single foot lesion. Most of the positive samples were from areas in the state of HP adjoining the state of Jammu and Kashmir (J&K), where footrot is endemic. The confirmation of footrot in HP and the fact that F. necrophorum and T pyogenes were detected from cases of foot/hoof infection in high numbers emphasises thatthese organisms play an important role in inducing morbidity in migratory sheep and goats. The present investigation also confirms the detection of D. nodosus from cases of footrot for the first time from HP. With new reports identifying F. necrophorum as a pathogen with a potential role in aggravating infection caused by footrot, the development of a combined vaccine to prevent lameness in sheep and goats in the north-western Himalayan region has been suggested.