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Good quality husk-caryopsis adhesion is essential for malting barley, but that quality is influenced by caryopsis surface lipid composition. Raman spectroscopy was applied to lipid extracts from barley caryopses of cultivars with differential adhesion qualities. Principal component regression indicated that Raman spectroscopy can distinguish among cultivars with good and poor quality adhesion due to differences in compounds associated with adhesion quality. • Quality of husk adhesion depends on differences in cementing layer composition • Raman spectra of cementing layer extracts show compositional changes among genotypes • Principal component regression is useful to predict adhesion quality among genotypes [ABSTRACT FROM AUTHOR]

Repetitive work is common in the modern workplace and the effects are often studied using fatigue protocols; however, there is evidence that the manner in which fatigue develops impacts the kinematic and muscular response to reduced physical capacity. The purpose of this study was to simultaneously evaluate muscular and kinematic adaptations during fatiguing, repetitive work until exhaustion. We measured muscle activity in 13 muscles in the shoulder and trunk, and captured full body kinematics while participants completed simulated, repetitive work tasks. Every 12 min, reference data were collected to quantify fatigue. This sequence continued until they reached the termination criteria. Participants displayed significant signs of muscle fatigue, loss of strength and increased perceived fatigue (p < 0.05). Analysis revealed a significant effect of time on posture and muscle activity that was both task and time dependent, and variable both between and within individuals. Participants were able to compensate for reduced physical capacity and maintain task performance through coordinated compensation strategies. [ABSTRACT FROM AUTHOR]

The EMG-force relationship changes with muscle fatigue, making interpretation of load sharing between muscles challenging. The purpose of this investigation was to evaluate the efficacy of normalizing EMG to repeated, static, submaximal exertions to mitigate fatigue artifacts in EMG amplitude (increased amplitude without muscle force change). Participants completed repetitive work tasks, in 60-second cycles, until exhaustion. Surface EMG was recorded from 11 shoulder muscles (anterior, middle and posterior deltoids, infraspinatus, upper, middle and lower trapezius, latissimus dorsi, serratus anterior, sternal and clavicular heads of pectoralis major). Every 12 min, participants completed 4 submaximal reference exertions. Reference exertion EMG data were used in 6 normalizing methods including 1 standard (normalized to initial reference exertion) and 5 novel methods: (i) Fatigue Only, (ii) Linear, (iii) Cubic, (iv) Points Forward, and (v) Points Forward/Backward. Data normalized with each novel method were compared to the Standard Method using mixed effects modelling. Significant differences depended on the muscle and the number of time points included (p < .05). The cubic model correlated better to the actual data points than linear predicted values. The novel cubic normalizing method created muscle activity ratios that appear to mitigate the fatigue effects and better reflect muscular loads during fatiguing work. [ABSTRACT FROM AUTHOR]

The shoulder allows kinematic and muscular changes to facilitate continued task performance during prolonged repetitive work. The purpose of this work was to examine changes during simulated repetitive work in response to a fatigue protocol. Participants performed 20 one-minute work cycles comprised of 4 shoulder centric tasks, a fatigue protocol, followed by 60 additional cycles. The fatigue protocol targeted the anterior deltoid and cycled between static and dynamic actions. EMG was collected from 14 upper extremity and back muscles and three-dimensional motion was captured during each work cycle. Participants completed post-fatigue work despite EMG manifestations of muscle fatigue, reduced flexion strength (by 28%), and increased perceived exertion (∼3 times). Throughout the post-fatigue work cycles, participants maintained performance via kinematic and muscular adaptations, such as reduced glenohumeral flexion and scapular rotation which were task specific and varied throughout the hour of simulated work. By the end of 60 post-fatigue work cycles, signs of fatigue persisted in the anterior deltoid and developed in the middle deltoid, yet perceived exertion and strength returned to pre-fatigue levels. Recovery from fatigue elicits changes in muscle activity and movement patterns that may not be perceived by the worker which has important implications for injury risk. [ABSTRACT FROM AUTHOR]

Upper extremity muscle fatigue is challenging to identify during industrial tasks and places changing demands on the shoulder complex that are not fully understood. The purpose of this investigation was to examine adaptation strategies in response to isolated anterior deltoid muscle fatigue while performing simulated repetitive work. Participants completed two blocks of simulated repetitive work separated by an anterior deltoid fatigue protocol; the first block had 20 work cycles and the post-fatigue block had 60 cycles. Each work cycle was 60s in duration and included 4 tasks: handle pull, cap rotation, drill press and handle push. Surface EMG of 14 muscles and upper body kinematics were recorded. Immediately following fatigue, glenohumeral flexion strength was reduced, rating of perceived exertion scores increased and signs of muscle fatigue (increased EMG amplitude, decreased EMG frequency) were present in anterior and posterior deltoids, latissimus dorsi and serratus anterior. Along with other kinematic and muscle activity changes, scapular reorientation occurred in all of the simulated tasks and generally served to increase the width of the subacromial space. These findings suggest that immediately following fatigue people adapt by repositioning joints to maintain task performance and may also prioritize maintaining subacromial space width. [ABSTRACT FROM AUTHOR]

Abstract: Pushing and pulling account for nearly half of all manual material handling tasks. The purpose of this investigation was to develop a 3-D spatial muscle activity map for the right upper extremity during pushing and pulling tasks. Nineteen males performed 140 ramped directional hand exertions (70 push; 70 pull) at locations along three axes aligned with the anatomical planes. Electromyography (EMG) of 14 sites on the right upper extremity was recorded. Two directional 3-way repeated measures ANOVAs assessed the influence of hand position on EMG. Hand position and exertion direction influenced total and individual muscle demand. During pulling exertions, all three hand location parameters influenced total muscle activity (p < 0.001) and similarly in pushing exertions (p < 0.002), though less pronounced than in pulling. Data were used to create equations to predict the muscle activity of untested hand locations for novel work design scenarios. [Copyright &y& Elsevier]

Despite growing literature, limited research details the influence of passive upper limb exoskeletons on upper limb kinematics. Two bolting tasks and a tracing task were completed at two heights (overhead and between waist and overhead height) for four exoskeleton conditions (no exoskeleton, and 3 levels of exoskeleton assistance) by female participants. Motion capture data, ratings of perceived exertion and discomfort, and task duration were recorded. Exoskeleton condition increased minimum shoulder elevation by 35-36% (Δ10.5-10.7°) at 1.81 kg and 2.72 kg of support, mean shoulder external rotation by 316% (Δ24.6°) at 0.91 kg of support and mean forearm pronation by 30.9% (Δ14.6°) at 0.91 kg of support. Exoskeleton condition reduced ratings of perceived exertion and discomfort, but not significantly. Task duration was unaffected. Exoskeleton use at any of three different settings modestly affected some joint kinematics for the tasks examined, which may merit consideration when deciding on occupational exoskeleton implementation. [ABSTRACT FROM AUTHOR]

Individuals can coordinate small kinematic changes at several degrees of freedom simultaneously in the presence of fatigue, leaving it unclear how overall biomechanical demands at each joint are altered. The purpose of this study was to evaluate trade-offs in joint moments between the trunk, shoulder, and elbow during repetitive upper extremity work. Participants performed four simulated workplace tasks cyclically until meeting fatigue termination criteria. Emergent fatigue-induced adaptations to repetitive work resulted in task-dependent trade-offs in joint moments. In general, reduced shoulder moments were compensated for by increased elbow and trunk joint moment contributions. Although mean joint moment changes were modest (range: 1-3 Nm) across participants, a wide distribution of responses was observed, with standard deviations exceeding 10 Nm. Re-distributing biomechanical demands across joints may alleviate constant tissue loads and facilitate continued task performance with fatigue but may be at the expense of increasing demands at adjacent joints. [ABSTRACT FROM AUTHOR]

Superior humeral head translation and scapula reorientation can reduce the subacromial space. While these kinematic abnormalities exist in injured populations, the effect of muscle fatigue is unclear. Additionally, these mechanisms were typically studied independently, thereby neglecting potential covariance. This research evaluated the influence of upper extremity muscle fatigue on glenohumeral and scapulothoracic kinematics and defined their relationship. Radiography and motion tracking systems captured these kinematic relationships, during scapula plane elevation, both before and after fatigue. Fatigue-induced changes in humeral head position, scapular orientation and the minimum subacromial space width were measured. High inter-subject variability existed for each measure which precluded identification of mean differences at the population level. However, significant scapular upward rotation occurred following fatigue (p=0.0002). Despite similar population mean results, between 39% and 57% of participants exhibited fatigue-related changes in disadvantageous orientations. Additionally, correlations between measures were generally fair (0.21-0.40) and highly dependent on elevation, likely attributed to the variable fatigue responses. Overall, the data confirms that fatigue-induced changes in kinematics poses highly variable risk of subacromial impingement syndrome across individuals. Thus, solely considering the "average" or mean population response likely underestimates potentially injurious fatigue consequences. [ABSTRACT FROM AUTHOR]

Abstract: Dissolved organic matter (DOM) is a ubiquitous constituent of natural waters and is comprised of a variety of chemically heterogeneous molecular structures and functional groups. DOM is often considered to be a major ligand for metals in most natural waters and its reactivity is thought to be strongly dependent on its chemical composition and structure. In this study, a combination of UV/visible, emission excitation matrix fluorescence (EEM) and 1H NMR spectroscopies were used to characterize DOM from the Athabasca River (Alberta, Canada). The chemical characterization of river DOM showed that the most upstream samples located in agricultural areas were blue-shifted and less aromatic and contained more hydrogens connected with oxygen functional groups than those in the wetland dominated area in the Athabasca oil sand deposit region. The presence of paramagnetic ions (Fe and Al) was not found to significantly affect the structural composition of DOM as revealed by 1H NMR. Such change in the quality of DOM may have a profound impact on metal binding in the Athabasca River watershed. [Copyright &y& Elsevier]

Abstract: Background: Adaptive aerosol delivery (AAD) nebuliser devices can reduce treatment times whilst enabling adherence to be monitored using inbuilt data logs. Using one such device, we have monitored nebulised antibiotic adherence in children with Cystic Fibrosis (CF). Methods: In CF children infected with Pseudomonas aeruginosa, downloaded data from an AAD device was used to calculate morning, evening and overall monthly adherence to antibiotic therapy over a year. Results: Overall monthly adherence to nebulised antibiotic therapy in 28 children was maintained between 60 and 70% over the year. Considerable variation in adherence, both between and within patients, was evident (Mean [SD] coefficient of variation, 37[44]%). Evening adherence (75[37]%) was better than morning adherence (58[34]%: p =0.012). Treatment regimens were changed in 8/28 patients based on adherence data. Conclusions: Routine adherence monitoring can be implemented in an outpatient setting. Using this type of information it is possible to identify which aspects of treatment can be improved and to work together with families to individualise treatments. [Copyright &y& Elsevier]

As the prevalence of obesity grows worldwide, it becomes an increasing concern in working populations. Ergonomists are faced with the challenge of accommodating workplace layouts to include this worker demographic. This study investigated the relationship between shoulder and low back isometric joint strengths across body mass index (BMI) groups. Additionally, relationships between body fat percentage (BF%), absolute strength, and strength normalized to body mass were examined. Ninety, healthy, working age participants performed 11 functional and isometric joint strength exertions. BMI group influenced normalized strength, as the obese 2+ (BMI >35.0) group had up to 63.1% lower joint strength than all other BMI groups (p < 0.05). Significant strong to moderate negative linear relationships existed between BF% and normalized strength for both males and females, and relationships were stronger for females. These strength deficits highlight the importance of considering body composition during ergonomics analyses and configuration of occupational tasks. [ABSTRACT FROM AUTHOR]

Drug-induced liver injury (DILI) is a major cause of acute liver failure (ALF) and one of the leading indications for liver transplantation in Western societies. Given the wide use of both prescribed and over the counter drugs, DILI has become a major health issue for which there is a pressing need to find novel and effective therapies. Although significant progress has been made in understanding the molecular mechanisms underlying DILI, our incomplete knowledge of its pathogenesis and inability to predict DILI is largely due to both discordance between human and animal DILI in preclinical drug development and a lack of models that faithfully recapitulate complex pathophysiological features of human DILI. This is exemplified by the hepatotoxicity of acetaminophen (APAP) overdose, a major cause of ALF because of its extensive worldwide use as an analgesic. Despite intensive efforts utilising current animal and in vitro models, the mechanisms involved in the hepatotoxicity of APAP are still not fully understood. In this expert Consensus Statement, which is endorsed by the European Drug-Induced Liver Injury Network, we aim to facilitate and outline clinically impactful discoveries by detailing the requirements for more realistic human-based systems to assess hepatotoxicity and guide future drug safety testing. We present novel insights and discuss major players in APAP pathophysiology, and describe emerging in vitro and in vivo pre-clinical models, as well as advanced imaging and in silico technologies, which may improve prediction of clinical outcomes of DILI. [ABSTRACT FROM AUTHOR]

Stress urinary incontinence (SUI) is common after radical prostatectomy and likely to persist despite conservative treatment. The sling is an emerging operation for persistent SUI, but randomised controlled trial (RCT) comparison with the established artificial urinary sphincter (AUS) is lacking. To compare the outcomes of surgery in men with bothersome urodynamic SUI after prostate surgery. A noninferiority RCT was conducted among men with bothersome urodynamic SUI from 27 UK centres. Blinding was not possible due the surgeries. Participants were randomly assigned (1:1) to the male transobturator sling (n = 190) or the AUS (n = 190) group. The primary outcome was patient-reported SUI 12 mo after randomisation, collected from postal questionnaire using a composite outcome from two items in validated International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form questionnaire (ICIQ-UI SF). Noninferiority margin was 15%, thought to be of acceptable lower effectiveness, in return for reduced adverse events (AEs) and easier operation, for the sling. Secondary outcomes were operative and postoperative details, patient-reported measures, and AEs, up to 12 mo after surgery. A total of 380 participants were included. At 12 mo after randomisation, incontinence rates were 134/154 (87.0%) for male sling versus 133/158 (84.2%) for AUS (difference 3.6% [95% confidence interval {CI} –11.6 to 4.6], p NI = 0.003), showing noninferiority. Incontinence symptoms (ICIQ-UI SF) reduced from scores of 16.1 and 16.4 at baseline to 8.7 and 7.5 for male sling and AUS, respectively (mean difference 1.4 [95% CI 0.2–2.6], p = 0.02). Serious AEs (SAEs) were few: n = 6 and n = 13 for male sling and AUS (one man had three SAEs), respectively. Quality of life scores improved, and satisfaction was high in both groups. All other secondary outcomes that show statistically significant differences favour the AUS. Using a strict definition, urinary incontinence rates remained high, with no evidence of difference between male sling and AUS. Symptoms and quality of life improved significantly in both groups, and men were generally satisfied with both procedures. Overall, secondary and post hoc analyses were in favour of AUS. Urinary incontinence after prostatectomy has considerable effect on men's quality of life. MASTER shows that if surgery is needed, both surgical options result in fewer symptoms and high satisfaction, despite most men not being completely dry. However, most other results indicate that men having an artificial urinary sphincter have better outcomes than those who have a sling. The results of this large, high-quality trial allow surgeons to discuss and recommend the use of both the artificial sphincter and the sling procedure for postprostatectomy incontinence, as the results with respect to urine leakage were similar. However, men will wish to know that the majority will have some persistent urinary incontinence, although satisfaction with surgery was high: in the artificial urinary sphincter (AUS) group 91% and 85% were, respectively, completely and fairly satisfied, and 85% would recommend an AUS to a friend; and in the sling group, 72% were completely or fairly satisfied and 72% would recommend a sling to a friend. Similarly, most of the other secondary outcomes favoured the AUS over the sling procedure. [ABSTRACT FROM AUTHOR]

The supraspinatus and infraspinatus muscles each have multiple sub-regions that may activate differentially in activities of daily living. Awareness of these differential demands critically informs rehabilitation of rotator cuff muscle following injury, particularly if centered on recovering and strengthening the rotator cuff to perform daily tasks. This study quantified muscle activation of supraspinatus and infraspinatus sub-regions during the performance of six activities of daily living. Twenty-three participants (mean: 22.6 ± 2.6 years) completed the following tasks: opening a jar, reaching at shoulder height, overhead reaching, pouring water from a pitcher, eating with a spoon, and combing hair. Indwelling electromyography was collected from the anterior and posterior supraspinatus and superior, middle, and inferior infraspinatus. Tasks requiring high arm elevations (e.g. reaching at shoulder and overhead height) activated anterior supraspinatus between 21 and 28% MVC. The posterior supraspinatus consistently activated between 10 and 30% MVC across all tasks. All sub-regions of infraspinatus activated highly (between 18 and 25% MVC) in tasks requiring high arm elevations in flexion. These findings may be leveraged to define effective measures to increase rotator cuff function in daily tasks. [ABSTRACT FROM AUTHOR]