pedal mechanics

INTRODUCTION: During the first wave of the COVID-19 pandemic, increasingly strict restrictions were imposed on the activities of the Swiss population, with a peak from 21 March to 27 April 2020. Changes in trauma patterns during the pandemic and the lockdown have been described in various studies around the world, and highlight some particularly exposed groups of people. The objective of this study was to assess changes in trauma-related presentations to the emergency department (ED) during the first wave of the COVID-19 pandemic, as compared to the same period in the previous year, with a particular focus on vulnerable populations...

Amateur or non-competitive cycling is one of the most popular and growing sports, and the repetitive nature of this sport, combined with a cleat position that is too far forward, often leads to peripheral ischemia or pressure, which can cause pain at the metatarsal level due to the nerve and vascular structures present at this level, according to several authors. This clinical series describes the work done to reduce pain in 21 cyclists who reported foot pain/discomfort exclusively during pedaling. To exclude different causes of pain, other than the position of the cleat, the cyclists received biomechanical assessments using an indoor bike smart trainer and a 2D motion capture system...

Perfect mechanical force effectiveness in cycling would be achieved if the forces applied to the pedal were perpendicular to the crank throughout the full crank cycle. However, empirical observations show that resultant pedal forces display substantial radial components in recreational and even highly-trained elite cyclists. Therefore, we hypothesized that attempting to maximize mechanical effectiveness during the entire downstroke of the pedal cycle must be associated with a penalty that outweighs the benefits of perfect effectiveness...

The arylazopyrazole 3pzH as a novel photoswitch exhibits quantitative switching and high thermal stability. In this work, combined electronic structure calculations and ab initio multiple spawning (AIMS) dynamic simulations were performed to systemically investigate the cis ↔ trans photoisomerization mechanism and the chiral preference after photoexcitation of 3pzH to the first excited singlet state (S1 ). Unlike most of the azoheteroarene photoswitches reported previously, many twisted and T-shaped cis isomers were found to be stable for 3pzH in the S0 state, owing to the moderate interaction between the hydrogen atom and π electrons of the aromatic ring...

This study investigates the impact of gravity on lower limb muscle coordination during pedaling. It explores how pedaling behaviors, kinematics, and muscle activation patterns dynamically adapts to changes in gravity and resistance levels. The experiment was conducted in parabolic flights, simulating microgravity, hypergravity (1.8 g), and normogravity conditions. Participants pedaled on an ergometer with varying resistances. The goal was to identify potential changes in muscle synergies and activation strategies under different gravitational contexts...

A 34-year-old non hypertensive, non-diabetic and ill looking weak woman came to our emergency department with shortness of breath NYHA III-IV, severe bilateral pedal edema extending up to the thighs and gross ascites. Physical examination revealed 3mm pitting ankle and leg edema and hemodynamically was stable with raised jugular venous pressure. There was a closing and opening mechanical click on Cardiac auscultation. At the lower left sternal border, there was grade 2/6 holodiastolic rumble and a grade 2/6 systolic murmur...

Despite advances in the clinical management of childhood acute myeloid leukemia (AML) during the last decades, outcome remains fatal in approximately one third of patients. Primary chemoresistance, relapse and acute and long-term toxicities to conventional myelosuppressive therapies still constitute significant challenges and emphasize the unmet need for effective targeted therapies. Years of scientific efforts have translated into extensive insights on the heterogeneous spectrum of genetics and oncogenic signaling pathways of AML and identified a subset of patients characterized by upregulation of HOXA and HOXB homeobox genes and myeloid ecotropic virus insertion site 1 (MEIS1)...

Snails employ a distinctive crawling mechanism in which the pedal waves travel along the foot and interact with the mucus to promote efficient movement on various substrates. Inspired by the concavities on the pedal wave, we develop a new bionic snail robot that introduces transverse patterns in a longitudinal wave to periodically change the friction. The poroelastic foam serves as flexible constraint and fills the robot's internal cavity. It contributes to the bending action, and maintains the thinness and softness of the robot...

BACKGROUND: Injuries, the leading cause of death in children 1-17 years old, are often preventable. Injury patterns are impacted by changes in the child's environment, shifts in supervision, and caregiver stressors. The objective of this study was to evaluate the incidence and proportion of injuries, mechanisms, and severity seen in Pediatric Emergency Departments (PEDs) during the COVID-19 pandemic. METHODS: This multicenter, cross-sectional study from January 2019 through December 2020 examined visits to 40 PEDs for children < 18 years old...

Eccentric (ECC) cycling, compared to traditional concentric cycling, has been shown to improve muscle strength and neuromuscular control at a lower metabolic cost. Despite the popularity of this exercise in the sports and rehabilitation contexts, there is a gap in our knowledge of which muscles are behaving eccentrically during ECC cycling. To this end, we used a musculoskeletal model and computer simulations to calculate joint kinematics and muscle lengths during ECC cycling. Movements were recorded using 3D motion capture technology while cycling eccentrically on a custom-built semi-recumbent ergometer...

In this work, a lateral moving multi-pedal DNA tetrahedron machine (MTM) is designed and coupled with dual-signal output system to construct a biomimetic electrochemical ratiometric strategy for ultrasensitive target DNA analysis. The tetrahedral structure provided rigid support for the pedal, ensuring efficient replacement of the rail chain modified with ferrocene. By conjugating cholesterol molecules to one vertex of MTM, it is decorated on a lipid bilayer. This molecular architecture confers lateral movement of MTM on an electrode surface while prevents its detachment from the system...

During the act of counting, our perceptual system may rely on information coming from different sensory channels. However, when the information coming from different sources is discordant, such as in the case of a de-synchronization between visual stimuli to be counted and irrelevant auditory stimuli, the performance in a sequential counting task might deteriorate. Such deterioration may originate from two different mechanisms, both linked to exogenous attention attracted by auditory stimuli. Indeed, exogenous auditory triggers may infiltrate our internal "counter", interfering with the counting process, resulting in an overcount; alternatively, the exogenous auditory triggers may disrupt the internal "counter" by deviating participants' attention from the visual stimuli, resulting in an undercount...

Athletes must transfer their performance when changing equipment due to innovative developments in sports technology. This kind of transfer has received only moderate attention. The aim of this study was to examine whether a mechanical change in sports equipment disturbs an athlete's performance and affects biomechanical and neurophysiological parameters. Therefore, an experiment was conducted in which 36 participants in three groups pedaled at 70 rounds per minute on a cycling ergometer with a circular and a noncircular (NC) chainring...

The ability to dynamically and reversibly control thermal transport in solid-state systems can redefine and propel a plethora of technologies including thermal switches, diodes, and rectifiers. Current material systems, however, do not possess the swift and large changes in thermal conductivity required for such practical applications. For instance, stimuli responsive materials, that can reversibly switch between a high thermal conductivity state and a low thermal conductivity state, are mostly limited to thermal switching ratios in the range of 1...

In the pond snail Lymnaea stagnalis , serotonin (5-HT) plays an important role in feeding behavior and its associated learning (e.g., conditioned taste aversion: CTA). The 5-HT content in the central nervous system (CNS) fluctuates with changes in the nutritional status, but it is also expected to be influenced by changes in the serotonin transporter (SERT) expression level. In the present study, we identified SERT in Lymnaea and observed its localization in 5-HTergic neurons, including the cerebral giant cells (CGCs) in the cerebral ganglia and the pedal A cluster neurons and right and left pedal dorsal 1 neurons in the pedal ganglia by in situ hybridization...

Developing biocomposites by hybridization, which is the combination of two or more materials, can be a potential solution for improving material recyclability and sustainability. This study focuses on creating a hybrid biocomposite reinforced with cotton-blended pineapple leaf fibre (PALF) fabric (174 GSM) and jute fibre fabric (265 GSM) which are thrown away by textile factories. The mechanical, moisture absorption, and vibration characteristics of four stacking sequences of hybrid composites and two unhybridized composites were analyzed...

BACKGROUND: The use of weightbearing images to diagnose foot and ankle injuries continues to offer hope for improved insight into pathologies, but weightbearing CT imaging has been limited by availability. The ability to apply force to the lower limb in a horizontal bore CT system may offer an adaptation to currently available imaging systems that provides access to weightbearing images without the acquisition of additional expensive imaging space or equipment. METHODS: In order to determine whether a horizontal CT system could produce the same results as a standing CT, 3 images of one foot from 10 subjects was obtained and standard measures were calculated...

Methylmercury (MeHg) readily accumulates in aquatic organisms while transferring and amplifying in the aquatic food chains. This study firstly explores the in vivo accumulation sites and metabolic regulation of MeHg in the rotifer Brachionus plicatilis by aggregation-induced emission fluorogen (AIEgen) and metabolomics. Fluorescent image analysis by AIEgen showed that MeHg in B. plicatilis mainly occured in the ciliary corona, esophagus, mastax, stomach and intestine in the direct absorption group. In the other group, where B...

BACKGROUND: The increased popularity of cycling is leading to an anticipated increase in cycling-related traffic accidents and a need to better understand the demographics and epidemiology of craniospinal injuries in this vulnerable road user group. This study aims to systematically investigate and characterise cycling-related head and spine injuries seen in the Major Trauma Centre for the Eastern region, which has the highest cycling rates in the UK. METHODS: We performed a retrospective cohort study comparing the incidence, patterns, and severity of head and spine injuries in pedal cyclists presenting to the Major Trauma Centre in Cambridge between January 2012 and December 2020...

The treatment of patients with balance disorders is an urgent problem to be solved by the medical community. The causes of balance disorders are diverse. An aging population, traffic accidents, stroke, genetic diseases and so on are all possible factors. It has brought great pain and inconvenience to patients and their families. At present, there are two main types of assisted rehabilitation training robots for patients with balance disorders: exoskeleton robots and end robots. The exoskeleton robot is generally installed on the outside of the patient's body to follow their movement, which can support the weight of the body and provide power support to help the patient train and recover lower limb ability...