Prediction of axial capacity of corrosion-affected RC columns strengthened with inclusive FRP

The primary cause behind the degradation of reinforced concrete (RC) structures is the propagation of corrosion in the steel-RC structures. Nowadays, numerous retrofitting techniques are available in the construction sector. Fiber-reinforced polymer (FRP) is one of the efficient rehabilitation measures that can be implemented on corroded structures to enhance structural capacities. However, the estimation of axial strength of FRP-strengthened columns affected by corrosion has been a challenging and tedious task in the laboratory as well as on the site. Considering such shortcomings, the prediction of axial capacity can be done using various analytical methods and artificial intelligence (AI) techniques. In this study, a comprehensive dataset of circular columns was extracted from the literature to predict the axial strength of FRP-wrapped and unstrengthened RC corroded columns. The laboratory results from the assembled dataset were compared to corresponding values estimated using relevant design codes provided by American Concrete Institute (ACI 440.2R-17 and ACI 318-19), and Bureau of Indian Standard (IS 456:2000). Five machine learning models were employed on columns to predict the axial load carrying capacity of FRP-strengthened and un-strengthened RC corroded columns. The results discovered that the extreme gradient boosting (XGBoost) model achieves superior accuracy with the least errors and could be used by the scientific community and FRP applicators to forecast the axial performance of corroded columns strengthened with and without FRP. The findings from the design codes revealed that prediction errors were available in high margins. Furthermore, feature importance analysis was conducted using the Shapley Additive exPlanation algorithm to know the contribution and influence of each input parameter on axial capacity. The feature analysis found that unconfined compressive strength of concrete plays an important role in deciding the axial capacity of columns. Moreover, to enhance the precision of axial capacity computation and improving the overall efficacy in engineering practice, a web-based user-friendly interface was developed for FRP applicators and engineers to simplify the process.

Effects of Stretching or Strengthening Exercise on Spinal and Lumbopelvic Posture: A Systematic Review with Meta-Analysis

BACKGROUND

Abnormal posture (e.g. loss of lordosis) has been associated with the occurrence of musculoskeletal pain. Stretching tight muscles while strengthening the antagonists represents the most common method to treat the assumed muscle imbalance. However, despite its high popularity, there is no quantitative synthesis of the available evidence examining the effectiveness of the stretch-and-strengthen approach.

METHODS

A systematic review with meta-analysis was conducted, searching PubMed, Web of Science and Google Scholar. We included controlled clinical trials investigating the effects of stretching or strengthening on spinal and lumbopelvic posture (e.g., pelvic tilt, lumbar lordosis, thoracic kyphosis, head tilt) in healthy individuals. Effect sizes were pooled using robust variance estimation. To rate the certainty about the evidence, the GRADE approach was applied.

RESULTS

A total of 23 studies with 969 participants were identified. Neither acute (d = 0.01, p = 0.97) nor chronic stretching (d=-0.19, p = 0.16) had an impact on posture. Chronic strengthening was associated with large improvements (d=-0.83, p = 0.01), but no study examined acute effects. Strengthening was superior (d = 0.81, p = 0.004) to stretching. Sub-analyses found strengthening to be effective in the thoracic and cervical spine (d=-1.04, p = 0.005) but not in the lumbar and lumbopelvic region (d=-0.23, p = 0.25). Stretching was ineffective in all locations (p > 0.05).

CONCLUSION

Moderate-certainty evidence does not support the use of stretching as a treatment of muscle imbalance. In contrast, therapists should focus on strengthening programs targeting weakened muscles.

Measurement of Knee Extensor Torque During Repetitive Peripheral Magnetic Stimulation: Comparison of the Forces Induced by Different Stimulators

Objective

To investigate the factors that induce strong contractions during repetitive peripheral magnetic stimulation (rPMS) and compare the muscle torque induced by two stimulators (Stim A and Stim B) with different coil properties.

Methods

rPMS was applied to the right vastus lateralis of 30 healthy young adults. Stim A contained a 10.1 cm2 rectangular iron core coil, while Stim B contained a 191 cm2 round coil. The knee extensor torque (KET) induced by rPMS at 30 Hz was measured isometrically and divided by the maximum voluntary contraction (MVC) to obtain a relative value of MVC (%MVC). KET at 100% intensity of Stim A (A100%, 1.08 T) was compared to those at 100% or 70% intensity of Stim B (B100%, 1.47 T vs. B70%, 1.07 T). Additionally, we conducted a comprehensive literature search for studies that measured the KET during rPMS.

Results

Both the mean values of %MVC using B100% and B70% were significantly greater than that using A100%. Furthermore, the KET induced by Stim B was found to be larger than that described in previous reports, unless booster units were used to directly stimulate the main trunk of the femoral nerve.

Conclusion

Stim B induced a stronger muscle contraction force than Stim A did. This may be because the larger the coil area, the wider the area that can be stimulated. Additionally, a circular coil allows for deeper stimulation.

Effects of high frequency strengthening on pain sensitivity and function in female runners with chronic patellofemoral pain

OBJECTIVE

To investigate the effects of a high frequency strengthening program on function, pain, and pain sensitization in female runners with chronic patellofemoral pain (PFP).

DESIGN

Cross-sectional study.

SETTING

University laboratory.

PARTICIPANTS

Thirty female runners (mean age 32 ± 8.1 years) with chronic PFP completed an 8-week home strengthening program.

MAIN OUTCOME MEASURES

Variables assessed at baseline, 8-weeks, and 12 weeks included single leg step down test (SLSD), pain, Anterior Knee Pain Scale (AKPS), University of Wisconsin Running Injury and Recovery Index (UWRI), and quantitative sensory testing.

RESULTS

There was large and statistically significant improvement at 8 and 12 weeks for average knee pain (ηp2 = 0.334, p < 0.001), worst knee pain (ηp2 = 0.351, p < 0.001), SLSD (ηp2 = 0.161, p = 0.001), AKPS (ηp2 = 0.463, p < 0.001), and UWRI (ηp2 = 0.366, p < 0.001). A medium to large effect and statistically significant improvement in pressure pain threshold testing was found for all local and remote structures (ηp2 range, 0.110 to 0.293, range p < 0.001 to p = 0.009) at 8 and 12 weeks.

CONCLUSIONS

There was a significant decrease in local and remote hyperalgesia via mechanical and thermal pain sensitivity testing in female runners with chronic PFP. There was a large effect and significant improvement in self-reported pain and function.

The influence of exercise on pain, disability and quality of life in office workers with chronic neck pain: A systematic review and meta-analysis

BACKGROUND

Exercise is recommended for office workers with neck pain. However, recent reviews evaluated the effectiveness of workplace interventions only.

OBJECTIVES

To evaluate the effect of exercise on pain, disability, and quality of life (QoL) in office workers with chronic neck pain.

DESIGN

Systematic review with meta-analysis.

METHODS

Electronic databases were searched from inception to April 30, 2022, to identify studies in which participants were adults aged ≥18 years undergoing any form of neck exercises (e.g., strengthening, motor control) or physical activity (e.g., aerobic exercise) performed for a minimum of two-weeks without any other additional treatment besides advice or education. Two reviewers independently screened papers and determined the certainty of the evidence.

RESULTS

Eight randomised controlled trials met the eligibility criteria. Seven studies reported a significant decrease in Visual Analogue Scale (VAS) scores for neck pain intensity and five studies reported a significant decrease in Neck Disability Index (NDI) scores following strengthening exercises. Only one study assessed the effect of strengthening exercises on QoL and reported no significant effect. All eight included studies had a high risk of bias and the overall certainty of evidence was low. Meta-analyses demonstrated a significant decrease of neck pain intensity and disability for strengthening exercises compared to a control (p < 0.01).

CONCLUSION

There is low certainty of evidence that strengthening of the neck, shoulder and scapular musculature is effective at reducing neck pain and disability in office workers. Further research evaluating the effect of exercise on QoL is required.

Phase transformation and strengthening of the gas-atomized FeCoCrNiMo0.5Al1.3 high-entropy alloy powder during annealing

Phase evolution and strengthening of the FeNiCoCrMo0.5Al1.3 powder alloy produced via inert gas atomization and annealed in the temperature interval of 300-800 °C have been studied by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and microhardness testing. It was found that annealing at 300-600 °C leads to an increase of the element segregations between the several solid solutions with a rise of the lattice misfit (ε) to 1.5 % and microhardness growth to 1070 HV. It was assumed that elastic stress caused by the element partitioning is the main strengthening mechanism: microhardness rises linearly with misfit rise with dHV/dε = 43400 MPa. Sigma arises after the maximum elastic deformation (in 1.5 %) was reached. Formation of the dispersed coherent sigma phase in the annealing interval 600-800 °C results in the microhardness rise. Oxidation that began at 800 °C in 27 h is accompanied with FCC formation due to a depletion of the B2 in Al caused by Al2O3 formation. Estimation of the activation energy of the initial stage of the solid solution decomposition gives a very low value in 0.65eV, apparently caused by the high concentration of quenched vacancies. The activation energy of sigma formation approximately coincides with the activation energy of self-diffusion in BCC metals (about 2.60 eV).

Optimizing primary health care in Burkina Faso: an approach informed by EQUIST

Introduction

Burkina Faso has made access to primary health care a national priority by including it in the 2021-2030 national health development plan.

Purpose of research

Our study aimed to analyze the causes of inequalities in access to primary health care, priority interventions and strategies for strengthening primary health care, and their potential impact on reducing maternal and infant mortality.

Results

Diarrheal diseases, malaria, and pneumonia are the main causes of inequalities in infant and child deaths in rural areas. As for maternal deaths, abortion and its complications are the main causes of inequalities in deaths associated with hypertensive disorders. The Sahel, Boucle du Mouhoun, Center-North, East, and Cascades regions are the geographical areas where interventions are essential to reduce inequalities in maternal, neonatal, infant and child deaths and malnutrition.

Conclusions

The national priorities have included all the high-impact interventions for strengthening primary health care identified in our study. Interventions must prioritize the populations in rural areas, the most affected and high-impact geographical regions. This requires the involvement and empowerment of beneficiary communities and the consideration of the fragile safety context.

Effectiveness of the "Evidence-Based Scientific Exercise Guidelines" in Increasing Cardiorespiratory Fitness, Cardiometabolic Health, and Muscle Strength in Acute Spinal Cord Injury Rehabilitation: A Systematic Review

Objective

To determine the effect of exercise and physical activity interventions that meet current guideline recommendations on cardiorespiratory fitness, cardiometabolic health, and muscle strength in adults in the acute stage (<1 year post onset) of spinal cord injury (SCI) rehabilitation.

Data Sources

Six electronic databases (PubMed, CINAHL, SPORTDiscus, Google Scholar, National Institute Clinical Excellence, World Health Organization) were searched (January 2016-March 2022) to extend a previously published review.

Study Selection

Included studies implemented exercise interventions in the acute stage of SCI rehabilitation participants which met the exercise guidelines and measured cardiorespiratory fitness, cardiometabolic health, and strength outcomes.

Data Extraction

Titles and abstracts were screened against eligibility criteria and duplicates removed using EndNote X8. Full texts were independently assessed and results presented in a Preferred Reporting Items for Systematic Reviews and Meta-Analyses flowchart. Data extraction was completed on included studies by 2 reviewers (L.R. and V.B.) using a modified Cochrane Group form.

Data Synthesis

Data were synthesized, appraised using the Modified Downs & Black checklist and presented in narrative and tabular format. This review was registered on PROSPERO (Register ID:CRD42021249441). Of the 1255 studies, 4 were included, featuring 108 total participants <1-year post-SCI. Functional electrical stimulation cycle ergometry reduced muscle atrophy after 3 months training and increased lean body mass after 6 months. Resistance training increased muscle peak torque, perceived muscle strength and function. Aerobic exercise interventions did not increase cardiorespiratory fitness.

Conclusions

Interventions meeting the exercise guidelines did not increase cardiorespiratory fitness but were shown to improve cardiometabolic health and perceived muscle strength and function in adults in the acute stage of SCI rehabilitation. Further empirical research using standardized outcome measures are required to explore the effectiveness of aerobic exercise and strengthening interventions in acute stage of SCI rehabilitation to support the development of exercise guidelines.

Strategies for maintaining and strengthening the health care workers during epidemics: a scoping review

INTRODUCTION

During epidemics such as COVID-19, healthcare workers (HCWs) face several challenges, leading to a shortage and weakening of human resources. To address this issue, employing effective strategies is essential in maintaining and strengthening human resources during outbreaks. This study aimed to gather and classify strategies that could retain and strengthen human health resources during epidemics.

METHODS

In this scoping review, all studies published about strategies for maintaining and strengthening HCWs in epidemics were collected from 4 international databases, including PubMed, Embase, Scopus, and Web of Science. The English language articles published after 2000 up until June 2022 recommended specific strategies regarding the research question. Then, they were analyzed and classified according to thematic analysis based on Braun and Clarke 6 phases protocols.

RESULTS

In total, 9405 records were screened, of which 59 articles were included, and their full texts were reviewed. Fifty factors were identified and classified into five themes: Instruction, Protection, Supporting, Caring, and Communication. Most of the suggestions were conducted in high-income countries and related to the Supporting theme.

DISCUSSION

The majority of strategies discussed in the literature addressed only one or two aspects of human resources. This study provides a holistic perspective on these issues by providing a thematic map of different strategies for strengthening and maintaining HCWs during epidemics. Considering the multidimensionality of human nature, it is suggested that policymakers and managers of health systems provide facilities that simultaneously address a wide range of needs.

Effect of case hardening on the wear and hardness properties of medium carbon steel for bone crushing application

The majority of wear-related problems are connected to crushing machines because hammer failure frequently causes machine failure which eventually leads to machine downtime. Therefore, improving the reliability of crushing materials is necessary for effective production. This research investigation focused on the development of crushing material with appropriate strength properties that can function in critical, impact-prone, corrosive, and abrasive conditions. The current study used palm kernel shell, coconut shell, and sawdust powder as the media for medium carbon steel in order to valorize the agro waste. Carburising media PKS-composition, CS-composition, and SD-composition were changed to 40%: 30%: 30%, PKS-composition 100%, CS-composition 100%, and SD-composition 100%. The process was carried out in 1 h (60 mims), 1 h:30 min (90 min), 2 h (120 min), 2 h:30 (150 min), and 3 h (180 min) soak period with varied carburising temperatures of 900, 950, 1000, and 1050 °C. However, several characterisation and mechanical tests were carried out using an optical microscope, a spark spectrometer, a scanning electron microscope coupled with an energy dispersive spectrometer, wear tester to explore their microstructural features. Vicker's hardness tester, sliding wear tester, and a thermal gravimetric analysis testing machine were also employed. In order to establish reasons for failure other than the cyclic loading on the materials, the results were compared with the properties of as-received un-failed, and carburised medium carbon steel. The results of carburisation show that PKS penetrates carbon at a rate that is noticeably higher than that of other materials at various temperatures and times, indicating that carbon diffuses deeply into the material. Hence, this enhances the wear resistance, and sample's hardness number but decreased its impact toughness respectively.

Disinsertion-distal myectomy and tucking of inferior oblique combined with superior oblique full tendon advancement in superior oblique palsy

PURPOSE

To assess the preliminary outcomes of inferior oblique (IO) disinsertion-distal myectomy and tucking combined with superior oblique (SO) full tendon advancement in patients with Knapp II or III superior oblique palsy.

METHODS

This single-centered retrospective study included 16 eyes from 13 patients with Knapp Class II or III SO palsy. All patients underwent IO disinsertion-distal myectomy and tucking combined with SO full tendon advancement while under general anesthesia. Pre- and post-operative levels of vertical deviation in the primary position, abnormal head position, IO hyperfunction and SO hypofunction, torsion, as well as the presence of diplopia, were all measured, and the differences were statistically compared.

RESULTS

Pre-operatively, 12 patients had abnormal head positions, and two had diplopia. The pre-and post-operative levels of IO hyperfunction and SO hypofunction, as well as a vertical deviation in the primary position and torsion, all differed statistically significantly (p < 0.01).

CONCLUSIONS

Inferior oblique disinsertion distal myectomy and tucking combined with SO full tendon advancement surgery appears to be an effective procedure in patients with congenital and acquired Knapp Class II or III SO palsy.

Brazilian Portuguese version and content validity of the Strengthening and Stretching for Rheumatoid Arthritis of the Hand (SARAH)

INTRODUCTION

The Strengthening and Stretching for Rheumatoid Arthritis of the Hand (SARAH) program is a personalized, progressive 12-week exercise program for people with hand problems due to rheumatoid arthritis (RA). Patients are provided with two guidance documents, the 'Patient Exercise Booklet' and the 'Personal Exercise Guide', to continue the exercises independently at home.

OBJECTIVE

This study aimed to translate and culturally adapt the SARAH protocol into Brazilian Portuguese and validate its content.

METHODS

The guidance documents 'Patient Exercise Booklet' and 'Personal Exercise Guide' of the SARAH program were translated and culturally adapted to Brazilian Portuguese. The content validity was obtained by calculating the content validity index (CVI).

RESULTS

The Brazilian version of the SARAH protocol reached semantic, idiomatic, conceptual, and cultural equivalences. The CVI was greater than 0.8, corresponding to a satisfactory index. The verbal comprehension was 4.9, showing good verbal comprehension of the target population.

CONCLUSION

The Brazilian Portuguese version of the SARAH protocol is available to Brazilian people with compromised hands due to RA with satisfactory content validity.

Biomass-derived polyphosphazene toward simultaneously enhancing the flame retardancy and mechanical properties of epoxy resins

As one of the most widely used polymers, the intrinsic brittleness and high flammability bring about a stringent requirement for the practical application of epoxy resins (EPs). It is difficult to toughen EP without compromising its mechanical and thermal properties for many conventional toughening agents. Here, a novel furan-derived bio-based polyphosphazene (PFMP) with a flexible backbone and rigid side groups was prepared by the nucleophilic substitution reaction between polydichlorophosphazene (PDCP) and furfuralcohol. The resultant PFMP was incorporated into EP to realize exceptional toughening, strengthening, and flame retardant function. By adding 15% of PFMP, the limit oxygen index value is from 25% (EP) to 33% (EP/PFMP-15) and reaches the UL-94 V-0 rating. According to the cone calorimeter results, EP/PFMP-15 exhibits exceedingly reduced peak heat release rate (pHRR) (50.2%) and total heat release (THR) (49.6%). The significantly increased fire performance index (FPI) and decreased fire growth rate index (FIGRA) of EP/PFMP-15 demonstrate an improvement in its flame retardancy. The catalytic carbonization effect (condensed phase) and radical quenching effect (gas phase) of PFMP account for the greatly improved flame retardancy. Moreover, the impact and tensile tests indicate that PFMP can ameliorate the mechanical performance of EP with a maximum increase of impact strength (111.8%) and elongation at break (35.2%) for EP/PFMP-5. With 15% PFMP added, the tensile strength of EP/PFMP-15 increases by 40.4%. This work demonstrates that PFMP is expected to overcome shortcomings (flammability, toughness, and strength) of EP and spread its applied fields.

Effects of the Counseling Program on Strengthening Mental-Crisis Management to Strengthen Adolescent Life Crisis Awareness

Background

A mental crisis is a dangerous state with many subsequent harmful effects on the adolescent. It is a state in which the adolescent needs help and must get that help immediately. If they do not receive the assistance they require, they may end up isolating themselves from social interaction and become completely preoccupied with themselves. The counseling program is therefore being put into effect to strengthen the mental crisis management capacity of adolescents and to offer counseling and assistance to students who find themselves beset with a mental crisis so that they will be fully able to manage their mental crises, restore a sense of balance to their psyches, and carry on with their lives effectively.

Objective

The aim of the study was to compare the life crisis awareness scores of adolescent students enrolled in a program of study at Thammasat University.

Methods

This research was quasi-experimental and consisted of a two-group pretest-post test design. They were subdivided into two groups of 30 students each by simple random sampling, of which one group was the experimental group and the other was control group. The experimental group underwent a counseling program of bolstering mental crisis management capacity once a week for a period of six weeks. Results were assessed using a crisis awareness evaluation form. Results were assessed twice, before testing and after testing. The data were analyzed by the statistics of percentage, mean, dependent t-test, and independent t-test.

Results

1. The average life crisis awareness scores of the adolescents in the experimental group following acceptance into the counseling program by fortifying their mental crisis management capacity (M=132.77, SD=11.03) were higher than they were prior to program entry (M=113.73, SD=14.40), with a statistical significance (t=6.81, p<0.001).2. The average life crisis awareness scores of the experimental group that had been accepted into the above-mentioned counseling program were higher after undergoing testing (M=132.77, SD=11.03) than the scores for the control group (M=118.83, SD=10.73), with a statistical significance (t=4.95, p<0.001).

Conclusion

This program thus helps the adolescent restore a sense of mental balance and live a normal happy life.

Effect of ultrasonic vibration on adhesive enhancement of plasma-modified nickel surface

Poor adhesion of nickel surface limits its further application in the aerospace field. In this study, plasma modification was conducted on the surface of the nickel plate pretreated by sandblasting, and then ultrasonic vibration was applied during the adhesively bonding process of the CFRP(Carbon fibre-reinforced polymer)/Ni joints. The bonding strength of the joints was increased by 65%. The adherend surface and the bonding interface were analyzed from microstructure, element distribution and chemical bonding to study the strengthening mechanism. By the sandblasting, irregular pits were formed on the nickel surface, effectively increasing the surface roughness. The plasma modification could introduce active functional groups including hydroxyl, amino and carbonyl on the nickel surface, which improved the surface wettability macroscopically. However, at a microscopic level, the adhesive with high viscosity and poor fluidity did not form a compact interface with the nickel. The ultrasonic application could promote the filling of the adhesive in irregular micro-scale pits on the surface, thereby strengthening the mechanical anchoring effect. Furthermore, the ultrasonic application produced dynamic impingement at the interface, enhancing the contact between the adhesive and the nickel plate. The adhesive molecules could fully collide and react with the active functional groups introduced on the nickel surface to form more chemical bonds, thus effectively improving the bonding strength of the CFRP/Ni joints.

Gelatin from leather waste to tough biodegradable packaging film: One valuable recycling solution for waste gelatin from leather industry

Large amount of gelatin can be extracted from the solid waste in leather industry. The advanced application of such gelatin is always desired by the leather industry, but remains challenging. Considering the urgent requirement of biodegradable plastic film, in this study, the gelatin extracted from waste skin scrap in the leather industry was used to fabricate a waste gelatin-based film with a high gelatin content, excellent mechanical performance, and autonomous biodegradability in natural soil. The film was prepared by introducing covalent bonds and metal-ligand bonds to the gelatin matrix. These covalent bonds, metal-ligand bonds, and inherent hydrogen bonds in the gelatin matrix serve as multiple sacrificial bonds for effective energy dissipation giving the waste gelatin-based film excellent mechanical parameters with the highest fracture stress of ≈ 32 MPa, maximum fracture strain of ≈1.25 mm/mm, and a high Young's modulus of ≈ 471 MPa, which are significantly higher than those of the original gelatin film (fracture stress ≈ 4 MPa, fracture strain ≈ 0.70 mm/mm, and Young's modulus ≈ 22 MPa). Owing to the water resistance of covalent bonds and metal-ligand bonds existed in gelatin matrix, the gelatin film possesses good water resistance. Additionally, after use, the fabricated film can completely biodegrade in natural soil in approximately 7 weeks. This strategy not only provides a valuable recycling solution for the gelatin from the unwelcome solid waste of the leather industry, but it also broadens the range of ecofriendly and cost effective biodegradable films available.

Intensive physiotherapy versus home-based exercise and custom-made orthotic insoles in patients with plantar fasciitis: Pilot study

BACKGROUND

This prospective pilot study assessed the feasibility of comparing intensive physiotherapy group (IPG), home-based exercise (HBEG) group, and insole group (IG) to find the most effective treatment program for plantar fasciitis.

METHODS

Thirty-nine individuals with plantar fasciitis were selected to participate in this pilot study. The patients were randomly divided into 3 groups, as IPG (manual interventions, exercise, insoles), HBEG (exercise, insoles), and IG (insoles). The feasibility details including percentage of the enrollment and adherence to the groups were recorded. Pain was measured with a visual analog scale, and dorsiflexion range of motion (DROM), foot function, and health-related quality of life were evaluated at the baseline and week 6. One-way ANOVA analysis and Kruskal Wallis test were used to determine the differences of the percentage change of the parameters.

RESULTS

Pain and functional evaluation results showed improvements clinically in all of groups and quality of life results were similar for all groups. There was no difference between the groups after 6 weeks of treatment (P > 0.05).

CONCLUSIONS

The 3 treatment programs were found clinically applicable with high patient adherence. According to the data all intervention types were found moderately effective for pain and function. Insoles could be an option applied alone or with other treatments, and manual techniques gave better results in patients with limited ankle dorsiflexion. Although the results should be interpreted with caution because of the small sample size, these results were found promising and feasible to conduct a future RCT.

CLINICAL TRIAL REGISTRATION NUMBER

RCT 06144834.

Effects of adding aerobic physical activity to strengthening exercise on hip osteoarthritis symptoms: protocol for the PHOENIX randomised controlled trial

BACKGROUND

Hip osteoarthritis (OA) is a leading cause of musculoskeletal pain. Exercise is a core recommended treatment. Most evidence is based on muscle-strengthening exercise, but aerobic physical activity has potential to enhance clinical benefits. The primary aim of this study is to test the hypothesis that adding aerobic physical activity to a muscle strengthening exercise leads to significantly greater reduction in hip pain and improvements in physical function, compared to a lower-limb muscle strengthening exercise program alone at 3 months.

METHODS

This is a superiority, 2-group, parallel randomised controlled trial including 196 people with symptomatic hip OA from the community. Following baseline assessment, participants are randomly allocated to receive either i) aerobic physical activity and muscle strengthening exercise or; ii) muscle strengthening exercise only. Participants in both groups receive 9 consultations with a physiotherapist over 3 months. Both groups receive a progressive muscle strengthening exercise program in addition to advice about OA management. The aerobic physical activity plan includes a prescription of moderate intensity aerobic physical activity with a goal of attaining 150 min per week. Primary outcomes are self-reported hip pain assessed on an 11-point numeric rating scale (0 = 'no pain' and 10 = 'worst pain possible') and self-reported physical function (Western Ontario and McMaster Universities Osteoarthritis Index physical function subscale) at 3 months. Secondary outcomes include other measures of self-reported pain (assessed at 0, 3, 9 months), self-reported physical function (assessed at 0, 3, 9 months), performance-based physical function (assessed at 0, 3 months), joint stiffness (assessed at 0, 3, 9 months), quality of life (assessed at 0, 3, 9 months), muscle strength (assessed at 0, 3 months), and cardiorespiratory fitness (assessed at 0, 3 months). Other measures include adverse events, co-interventions, and adherence. Measures of body composition, serum inflammatory biomarkers, quantitative sensory measures, anxiety, depression, fear of movement and self-efficacy are included to explore causal mechanisms.

DISCUSSION

Findings will assist to provide an evidence-based recommendation regarding the additional effect of aerobic physical activity to lower-limb muscle strengthening on hip OA pain and physical function.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry reference: ACTRN 12619001297112. Registered 20th September 2019.

The supralaryngeal articulation of stress and accent in Greek

It is well reported that articulatory movements comprising prominence units are longer, larger and faster than their non-prominent counterparts. However, it is unclear whether these effects arise at the level of lexical stress or accent or both, reflecting a hierarchy of prominence, i.e., being stronger when induced by accent as opposed to stress. It is also uncertain whether prominence-induced kinematic effects are invariant across positions of stress within the word, types of focus the accent denotes, and positions of words in the phrase. We conduct an electromagnetic articulography (EMA) study to assess the supralaryngeal kinematic correlates of prominence in Greek across three stress positions (antepenultimate, penultimate, ultimate; i.e., all possible stress positions in Greek), two accentual conditions (accented and de-accented) and two phrasal positions (phrase-medial and phrase-final). Focus type is also considered, with the accentual conditions coming from two types of focus (broad and narrow), while the de-accented conditions are by default unfocused. Our results indicate that stressed syllables involve longer, larger and faster gestures than their unstressed counterparts, regardless of the position of stress within the word. Notably, variation in velocity is accounted for by variation in displacement. Presence of accent does not further expand the stressed gestures, although it is related to minimal kinematic changes across the whole word, the exact profile of which depends on stress position. With the exception of final vowel duration, focus type is not systematically encoded in these kinematic effects. Finally, interactions are detected between the kinematic profile of prominence and that of boundaries. Implications of our findings for the hierarchy of prominence and cross-linguistic differences are discussed, and a gestural account of prominence and boundaries is put forward.

Muscle strength gains after strengthening exercise explained by reductions in serum inflammation in women with knee osteoarthritis

Background Individuals with knee osteoarthritis have elevated circulating inflammatory markers and altered cartilage properties but it is unclear if these features adapt to exercise. We aimed to determine (1) whether inflammatory markers, cartilage transverse relaxation time and thickness mediate the effect of body mass index (BMI) on quadriceps strength at baseline; and (2) whether these changes explain variance in quadriceps strength improvements after 12 weeks of exercise in women with knee osteoarthritis. Methods This secondary analysis (17 women with clinical knee osteoarthritis) of a randomized control trial compared supervised group interventions, 3 times/week for 12 weeks (36 sessions): (a) weight-bearing progressive resistive quadriceps exercise or (b) attention control. (1) From baseline, separate linear regressions were conducted with strength (Nm/kg) as the dependent, BMI as the predictor, and c-reactive protein, tumor necrosis factor, interleukin-6, cartilage transverse relaxation time or thickness as potential mediators. (2) Multiple linear regression analyses were completed with 12-week strength change (post-pre) as the dependent, change in serum inflammatory markers and cartilage measurements as predictors, and age, BMI and adherence as covariates. Findings (1) At baseline, there was no mediation. (2) A decrease in each of interleukin-6 (β = -0.104 (95% confidence intervals: -0.172, -0.036), R² = 0.51, P < 0.007) and tumor necrosis factor (β = -0.024 (-0.038, -0.009), R² = 0.54, P < 0.005) was associated with strength gains. Interpretation At baseline, inflammatory markers and cartilage measurements do not act as mediators of BMI on quadriceps strength. After 12 weeks of exercise, reduced interleukin-6 and tumor necrosis factor were associated with increased quadriceps strength in women with knee osteoarthritis.

Effects of bi-axial ankle strengthening on muscle co-contraction during gait in chronic stroke patients: A randomized controlled pilot study

INTRODUCTION

Ankle dysfunction in patients with stroke is a common but serious cause of balance and gait impairments. However, comprehensive paretic ankle training seldom exists. Thus, we investigated the effects of a bi-axial ankle muscle training program using visual feedback as a means to improve ankle strength and performance of functional activities in patients with stroke.

METHODS

This study was a randomized controlled pilot trial with concealed allocation and assessor blinding and intention-to-treat analysis. Twenty-five patients with stroke and difficulty in walking (e.g., foot drop) or ankle muscle weakness receiving inpatient rehabilitation were included. The experimental group underwent ankle muscle training consisting of passive stretching, control of ankle muscles, and active-resistive strengthening using visual feedback for 40 min per day, 5 times per week for 4 weeks. The control group underwent ankle-related physical therapy, including ankle range-of-motion exercises. The amount of time for training was equal between the two groups. The outcome measurements were isometric ankle contraction force to assess the strength of ankle muscles, ankle proprioception, Fugl-Meyer lower extremity score, Berg balance scale score, walking speed, and ankle co-contraction index to assess muscle efficiency during gait.

RESULTS

The analysis revealed significant between-group differences in the ankle muscle strength in each direction (P < 0.05), Fugl-Meyer score (P < 0.01), and stance-phase co-contraction index (P < 0.05). After training, the experimental group displayed significant within-group differences in the strength of the ankle muscles in each direction (P < 0.01), ankle proprioception (P < 0.05), and walking speed (P < 0.05).

CONCLUSIONS

Our findings demonstrate the significant short-term effects of ankle muscle training on strength, walking speed, and muscle efficiency in patients with chronic stroke.

A review on alloy design, biological response, and strengthening of β-titanium alloys as biomaterials

From the past few years, developments of β-Ti alloys have been the subject of active research in the medical domain. The current paper highlights significant findings in the area of β-Ti alloy design, biological responses, strengthening mechanisms, and developing low-cost implants with a high degree of biocompatibility. It is evident that an astonishing demand for developing the low modulus-high strength implants can be fulfilled by synchronizing β stabilizer content and incorporating tailored thermo-mechanical techniques. Furthermore, the biological response of the implants is as important as the physical properties that regulate healing response; hence, the optimum selection of alloying elements plays a curial role for clinical success. The paper also presents the evolution of patents in this field from the year 2010 to 2020 showing the relevant innovations that may benefit a wide range of researchers.

Glucaric acid additives for the antiplasticization of fibers wet spun from cellulose acetate/acetic acid/water

Cellulose acetate (CA) receives notable attention as an environmentally friendly, biodegradable polymer from renewable, low-cost resources. CA polymers are believed to have a critical role in shaping a greener and more circular textile economy. However, the mechanical properties of CA fibers are among the lowest in terms of its tensile strength, poor wet strength, and low flexural strength. This study investigates the effect of biobased additives for antiplasticizing the mechanical performance and structure of CA fibers. At up to 5 % of CA, glucaric acid (GA) and its monoammonium salt were added to CA fibers. With 1.5 % GA additive, tensile modulus improved by 155%, tensile strength by 55 %, and CA flexibility according to knot to straight fiber tenacity ratios improved by 107 % when compared to neat CA fibers. Based on the results, green small molecule antiplasticizers do exist, but their performance improvements are observed at low percentages of loading.

Chromium carbide micro-whiskers dataset: Morphologies with scanning and transmission electronic microscopy

Chromium carbide exhibits a superior set of mechanical properties and chemical stabilities and is widely used in various engineering applications. Here, micro-whiskers of the Cr₂O₃ were successfully prepared using a carbothermal reduction method with high energy milling and liquid phase catalysis. The whiskers growth was observed with scanning electron microscopy and field emission gun transmission electron microscopy. This dataset shows all kinds of morphologies of the Cr₂O₃ whiskers during the growth stage, including agglomerated, pointed, and non-whiskered shapes, which are products of the mixture of Cr₂O₃:C = 1:5 or 1:8 or 1:10 under different temperatures and duration time. These data provide important additional information different from the source article but complement it with some negative but indicative and instructive data. Experimental scientists who want to investigate the growth and strengthening of whiskers of Cr₂O₃ or others can refer to and benefit from these data, such as possible combinations of the experimental conditions which may lead to certain outcomes and guide the predictive design of future relevant research with similar materials system.