Compensatory Patterns Research Articles

Assessment of compensatory growth in stunted fingerlings of Snubnose pompano, Trachinotus blochii (Lacepede, 1801), in marine conditions

The authors share no conflict of interest regarding this research publication. A part of the information in the research work has been published as an abstract for the international conference, Asian-Pacific Aquaculture 2019, Held at Chennai, India, during 19–21 June 2019. Suresh Babu, P. P*., Abdul Nasar, A. K., Jayakumar, R., Anikuttan, K. K., Imelda Joseph, Boby Ignatius, Shilta, M. T., Anuraj A. Jaysree Loka, Praveen Dube and 328 Shinoj. P. 2019. Compensatory growth pattern in stunted fingerlings of silver pompano in two different salinity regimes. https://www.was.org/Meeting/Program/PaperDetail/153528

Center of pressure predicts Intra-limb compensatory patterns that shift demands away from knee extensors during squatting

The persistence of knee extensor moments deficits following anterior cruciate ligament reconstruction (ACLr) may be attributed to difficulty quantifying inter- and intra-limb compensations clinically. Force plate derived center of pressure (CoPpos) and vertical force (vGRF) may provide valuable information regarding limb and joint loading impairments in this group. This study aimed to determine the: 1) relationship between measures CoPpos and intra-limb extensor moment distribution during a squat, and 2) utility of using CoPpos and vGRF to estimate knee extensor moment deficits post-ACLr. Twenty-four individuals, 142 ± 22.5 days post-ACLr, performed bilateral squats. Ankle (aEXT), knee (kEXT) and hip (hEXT) extensor moments were calculated using three-dimensional kinematics and GRF. Moments, CoPpos and vGRF were identified at peak kEXT. Intra-limb moment distribution was characterized using hEXT/kEXT and aEXT/kEXT ratios. Linear regressions analyzed relationships between CoPpos and hEXT/kEXT and aEXT/kEXT. Stepwise regressions determined if between-limb CoPpos ratio predicted between-limb ratios of hEXT/kEXT and aEXT/kEXT. Stepwise regression determined if between-limb CoPpos and vGRF ratios predicted between-limb kEXT ratio. Results found that CoPpos predicts intra-limb moment distribution (hEXT/kEXT and aEXT/kEXT); more anterior CoPpos related to higher moments at the hip and ankle relative to the knee. In addition, between-limb CoPpos ratio predicts between-limb ratio of hEXT/kEXT and aEXT/kEXT ratios. Together between-limb CoPpos (52%) and vGRF (18%) ratios explained 70% of the variance in between-limb kEXT ratios (R2 = 0.70, p < 0.001). These data suggest that force plate derived CoPpos and vGRF may be important for detection of knee extensor moment deficits in individuals post-ACLr.

Polycyclic Aromatic Hydrocarbon-induced Pulmonary Carcinogenesis in Cytochrome P450 (CYP)1A1- and 1A2-Null Mice: Roles of CYP1A1 and CYP1A2.

In 2019, lung cancer was estimated to be the leading cause of cancer deaths in humans. Polycyclic aromatic hydrocarbons (PAHs) are known to increase the risk of lung cancer. PAHs are metabolized by the cytochrome P450 (CYP)1A subfamily, comprised of the CYP1A1 and 1A2 monooxygenases. These enzymes bioactivate PAHs into reactive metabolites that induce mutagenic DNA adducts, which can lead to cancer. Past studies have investigated the role of CYP1A1 in PAH bioactivation; however, the individual roles of each CYP1A enzyme are still unknown. In this investigation, we tested the hypothesis that mice lacking the genes for Cyp1a1 or Cyp1a2 will display altered susceptibilities to PAH-induced pulmonary carcinogenesis. Wild-type, Cyp1a1-null (Cyp1a1-/-), and Cyp1a2-null (Cyp1a2-/-) male and female mice were treated with 3-methylcholanthrene for cancer initiation and tumor formation studies. In wild-type mice, CYP1A1 and 1A2 expression was induced by 3-methylcholanthrene. Cyp1a1-/- and Cyp1a2-/- mice treated with PAHs displayed a compensatory pattern, where knocking out 1 Cyp1a gene led to increased expression of the other. Cyp1a1-/- mice were resistant to DNA adduct and tumor formation, whereas Cyp1a2-/- mice displayed increased levels of both. UALCAN analysis revealed that lung adenocarcinoma patients with high levels of CYP1A2 expression survive significantly better than patients with low/medium expression. In conclusion, Cyp1a1-/- mice were less susceptible to PAH-induced pulmonary carcinogenesis, whereas Cyp1a2-/- mice were more susceptible. In addition, high CYP1A2 expression was found to be protective for lung adenocarcinoma patients. These results support the need to develop novel CYP1A1 inhibitors to mitigate human lung cancer.

Evaluation of spinal posture during gait with inertial measurement units.

The increasing number of postural disorders emphasizes the central role of the vertebral spine during gait. Indeed, clinicians need an accurate and non-invasive method to evaluate the effectiveness of a rehabilitation program on spinal kinematics. Accordingly, the aim of this work was the use of inertial sensors for the assessment of angles among vertebral segments during gait. The spine was partitioned into five segments and correspondingly five inertial measurement units were positioned. Articulations between two adjacent spine segments were modeled with spherical joints, and the tilt-twist method was adopted to evaluate flexion-extension, lateral bending and axial rotation. In total, 18 young healthy subjects (9 males and 9 females) walked barefoot in three different conditions. The spinal posture during gait was efficiently evaluated considering the patterns of planar angles of each spine segment. Some statistically significant differences highlighted the influence of gender, speed and imposed cadence. The proposed methodology proved the usability of inertial sensors for the assessment of spinal posture and it is expected to efficiently point out trunk compensatory pattern during gait in a clinical context.

Preoperative And Postoperative Cycling Biomechanics Following Cam Femoroacetabular Impingement Corrective Surgery: A Pilot Study

PURPOSE: Cycling is commonly prescribed following femoroacetabular impingement (FAI) corrective surgery. This surgery alters gait mechanics in the postoperative period, but alterations in cycling mechanics have not been reported. In this case study, we sought to determine if cam FAI corrective surgery altered cycling biomechanics postoperatively in a highly active female subject. METHODS: Bilateral cycling biomechanics were collected preoperatively when the subject was asymptomatic and again 11-weeks postoperatively. During each visit, pedal forces and limb kinematics were collected and used to determine joint-specific work. The subject was instructed to target a power output of 240 W during isokinetic cycling at 80 RPM. Limb symmetry index (LSI) was calculated to compare power production at the pedal. Normalized joint-specific work was compared both inter- and intralimb, as well as pre- vs. postoperatively. RESULTS: LSI decreased from 96% to 84% postoperatively. Summed joint extension work increased in the surgical limb from 90% to 97% postoperatively. This increase was the result of a 67% decrease in hip extension work (30% to 10%, Figure 1) and a compensatory 28% increase in knee extension (50% to 64%, Figure 1) and 70% increase in ankle extension (10% to 17%, Figure 1) work within the surgical limb. In the nonsurgical limb, there was a 333% increase in knee flexion work postoperatively (3% to 13%, Figure 1). CONCLUSION: Cycling mechanics following FAI corrective surgery exhibited significant changes suggesting the development of compensatory patterns. The results of this pilot study combined with the prevalence of cycling in FAI surgery rehabilitation warrant further studies on the development and persistence of compensatory patterns and to possibly identify early intervention strategies.

Systematic manipulations of the biological stress systems result in sex-specific compensatory stress responses and negative mood outcomes.

Women are twice as likely as men to be diagnosed with anxiety and mood disorders. One potential underlying mechanism is sex differences in physiological and psychological responses to stress; however, no studies to date have investigated this proposed mechanism experimentally. In a double-blind, placebo-controlled design, pharmacological challenges were administered to individually suppress the hypothalamic-pituitary-adrenal (HPA) axis, or the sympathetic nervous system (SNS) prior to stress exposure, to investigate sex differences in the resulting cross talk among the physiological and psychological stress responses. Sex-specific compensatory patterns and psychological effects emerged when the stress systems were manipulated. Men demonstrated heightened SNS reactivity to stress when the HPA axis was suppressed, and greater HPA reactivity after SNS suppression. This ability to react appropriately to the stressor, even with one system, did not lead to significant negative mood effects. In women, higher baseline activation (but dampened reactivity to stress) of SNS or HPA was observed when the other system was suppressed. This was coupled with worsened mood in response to stress when either stress system was compromised. Our results indicate that men and women may be differentially sensitive to fluctuations of their stress systems. This might be a potential link that underlies the sexual dimorphism in vulnerability for psychopathology.

Postictal stertor: Associations with focal and bilateral seizure types

ObjectiveThe objective of the present study was to determine the association between respiratory stertor and focal and bilateral seizure types. MethodsWe characterized ictal and postictal behaviors during symmetric bilateral tonic–clonic (TC) and asymmetric TC seizures in the Johns Hopkins University (JHU) epilepsy monitoring unit, comparing these to focal unaware seizures. We measured the presence and duration of postictal stertorous respirations, postictal generalized electroencephalographic suppression (PGES), immobility/motor dysfunction, and encephalopathy and determined their associations and relationship to seizure types. ResultsIn initial seizures recorded in 80 consecutive patients, bilateral symmetric TC seizures (N = 35) were strongly associated with PGES (97%, p < 0.001) and postictal stertorous respirations (89%, p < 0.001). Only 10% of the 20 patients with asymmetric TC seizures had brief PGES; focal unaware seizures (N = 25) were not associated with PGES or stertorous breathing. Some patients (24%) with asymmetric or bilateral symmetric TC seizures had severe postictal encephalopathy with stertor that was separate or extended beyond periods of PGES. ConclusionBilateral symmetric TC seizures, but not focal unaware seizures, have postictal stertor during PGES. Severe postictal encephalopathy, however, is also associated with motor dysfunction and stertor. Stertor appears to be a compensatory postictal respiratory pattern for ictal/postictal hypoxemia and occurs with PGES or postictal encephalopathy.

The association between cognitive reserve and performance-related brain activity during episodic encoding and retrieval across the adult lifespan

Remembering associations between encoded items and their contextual setting is a feature of episodic memory. Although this ability generally deteriorates with age, there is substantial variability in how older individuals perform on episodic memory tasks. A current topic of debate in the cognitive neuroscience of aging literature revolves around whether this variability may stem from genetic and/or environmental factors related to reserve, allowing some individuals to compensate for age-related decline through differential recruitment of brain regions. In this fMRI study spanning a large adult lifespan sample (N = 154), we tested whether higher cognitive reserve was associated with better task-fMRI context memory performance, and functional compensatory activity patterns in the aging brain. We used multivariate Behaviour Partial Least Squares (B-PLS) analysis to examine how age, retrieval accuracy, and a proxy measure of cognitive reserve [i.e., a composite score consisting of years of education (EDU) and crystallized IQ], impacted brain activity during the encoding and retrieval of spatial and temporal contextual details. The results indicated that age-related increases in encoding activity within anterior and lateral frontal, inferior parietal, occipito-temporal and medial temporal cortices, was correlated with better subsequent memory performance; and may be indicative of age-related functional compensation at encoding. Interestingly this compensatory pattern was not correlated with our proxy measure of cognitive reserve but was associated with total brain volume (a measure of brain reserve). However, cognitive reserve was associated with age-invariant and task-general activity in superior temporal, occipital, and left inferior frontal regions. We conclude that the relationship between cognitive reserve, brain reserve and age-related functional compensation is complex, and that EDU and IQ may not fully account for individual differences in cognitive reserve when studying well educated, healthy aging cohorts.

Altered Corticomuscular Coherence (CMCoh) Pattern in the Upper Limb During Finger Movements After Stroke.

Background: Proximal compensation to the distal movements is commonly observed in the affected upper extremity (UE) of patients with chronic stroke. However, the cortical origin of this compensation has not been well-understood. In this study, corticomuscular coherence (CMCoh) and electromyography (EMG) analysis were adopted to investigate the corticomuscular coordinating pattern of proximal UE compensatory activities when conducting distal UE movements in chronic stroke.Method: Fourteen chronic stroke subjects and 10 age-matched unimpaired controls conducted isometric finger extensions and flexions at 20 and 40% of maximal voluntary contractions. Electroencephalogram (EEG) data were recorded from the sensorimotor area and EMG signals were captured from extensor digitorum (ED), flexor digitorum (FD), triceps brachii (TRI), and biceps brachii (BIC) to investigate the CMCoh peak values in the Beta band. EMG parameters, i.e., the EMG activation level and co-contraction index (CI), were analyzed to evaluate the compensatory muscular patterns in the upper limb.Result: The peak CMCoh with statistical significance (P < 0.05) was found shifted from the ipsilesional side to the contralesional side in the proximal UE muscles, while to the central regions in the distal UE muscle in chronic strokes. Significant differences (P < 0.05) were observed in both peak ED and FD CMCohs during finger extensions between the two groups. The unimpaired controls exhibited significant intragroup differences between 20 and 40% levels in extensions for peak ED and FD CMCohs (P < 0.05). The stroke subjects showed significant differences in peak TRI and BIC CMCohs (P < 0.01). No significant inter- or intra-group difference was observed in peak CMCoh during finger flexions. EMG parameters showed higher EMG activation levels in TRI and BIC muscles (P < 0.05), and higher CI values in the muscle pairs involving TRI and BIC during all the extension and flexion tasks in the stroke group than those in the control group (P < 0.05).Conclusion: The post-stroke proximal muscular compensations from the elbow to the finger movements were cortically originated, with the center mainly located in the contralesional hemisphere.

Evaluating Immediate Benefits of Assisting Knee Extension With a Soft Inflatable Exosuit

Wearable robots such as powered exoskeletons and exosuits have been developed for gait assistance and rehabilitation. However, effects of knee extension assistance during the swing phase and initial stance of walking remains largely unknown. This work studies the changes in gait patterns for seven healthy participants and three impaired participants when knee extension in the swing and initial stance phases is assisted by a soft inflatable exosuit. The kinematics, surface electromyographic (sEMG) activity, and ground reaction forces (GRFs) for seven healthy participants during treadmill walking are recorded. Reductions in knee angle and sEMG activity of the quadriceps are observed. The knee angles, GRFs, spatiotemporal parameters, and compensatory gait patterns are studied for the three impaired participants for treadmill walking. Reductions in the knee angle, hip flexion, step length, and step time are observed. Compensatory gait patterns for the three participants varied for all participants. A timed up-and-go (TUG) test is also performed with the impaired participants during overground walking. A reduced TUG execution time is observed, indicating potential improvement in functional mobility. Overall, this work provides preliminary evidence on the benefits of a soft-exosuit in supporting healthy individuals and improving the rehabilitation of stroke survivors by assisting knee extension in the swing and initial stance phases.

Online compensation detecting for real-time reduction of compensatory motions during reaching: a pilot study with stroke survivors

BackgroundCompensations are commonly observed in patients with stroke when they engage in reaching without supervision; these behaviors may be detrimental to long-term functional improvement. Automatic detection and reduction of compensation cab help patients perform tasks correctly and promote better upper extremity recovery.ObjectiveOur first objective is to verify the feasibility of detecting compensation online using machine learning methods and pressure distribution data. Second objective was to investigate whether compensations of stroke survivors can be reduced by audiovisual or force feedback. The third objective was to compare the effectiveness of audiovisual and force feedback in reducing compensation.MethodsEight patients with stroke performed reaching tasks while pressure distribution data were recorded. Both the offline and online recognition accuracy were investigated to assess the feasibility of applying a support vector machine (SVM) based compensation detection system. During reduction of compensation, audiovisual feedback was delivered using virtual reality technology, and force feedback was delivered through a rehabilitation robot.ResultsGood classification performance was obtained in online compensation recognition, with an average F1-score of over 0.95. Based on accurate online detection, real-time feedback significantly decreased compensations of patients with stroke in comparison with no-feedback condition (p < 0.001). Meanwhile, the difference between audiovisual and force feedback was also significant (p < 0.001) and force feedback was more effective in reducing compensation in patients with stroke.ConclusionsAccurate online recognition validated the feasibility of monitoring compensations using machine learning algorithms and pressure distribution data. Reliable online detection also paved the way for reducing compensations by providing feedback to patients with stroke. Our findings suggested that real-time feedback could be an effective approach to reducing compensatory patterns and force feedback demonstrated a more enviable potential compared with audiovisual feedback.

Relationship of gait complexity to subsequent knee buckling and falls: the most study

Purpose: Stable gait relies on the flexibility and adaptability of the neuromuscular control system. A loss of physiological complexity is a characteristic of pathological conditions as well as decreased ability with senescence to adapt to daily stressors. Knee OA is often accompanied by compensatory gait patterns, such as repetition of a specific motion pattern indicating a loss of gait complexity and reduced adaptability. Prior studies show that reduced gait complexity is associated with falls in frail elders and people with neurodegenerative diseases, as well as with worsening physical function in persons with, or at increased risk for, knee OA.

Representation of viewed and recalled film clips in patterns of brain activity in a person with developmental amnesia

As clear memories transport us back into the past, the brain also revives prior patterns of neural activity, a phenomenon known as neural reactivation. While growing evidence indicates a link between neural reactivation and typical variations in memory performance in healthy individuals, it is unclear how and to what extent reactivation is disrupted by a memory disorder. The current study characterizes neural reactivation in a case of amnesia using Multivoxel Pattern Analysis (MVPA). We tested NC, an individual with developmental amnesia linked to a diencephalic stroke, and 19 young adult controls on a functional magnetic resonance imaging (fMRI) task during which participants viewed and recalled short videos multiple times. An encoding classifier trained and tested to identify videos based on brain activity patterns elicited at perception revealed superior classification in NC. The enhanced consistency in stimulus representation we observed in NC at encoding was accompanied by an absence of multivariate repetition suppression, which occurred over repeated viewing in the controls. Another recall classifier trained and tested to identify videos during mental replay indicated normal levels of classification in NC, despite his poor memory for stimulus content. However, a cross-condition classifier trained on perception trials and tested on mental replay trials—a strict test of reactivation—revealed significantly poorer classification in NC. Thus, while NC's brain activity was consistent and stimulus-specific during mental replay, this specificity did not reflect the reactivation of patterns elicited at perception to the same extent as controls. Fittingly, we identified brain regions for which activity supported stimulus representation during mental replay to a greater extent in NC than in controls. This activity was not modeled on perception, suggesting that compensatory patterns of representation based on generic knowledge can support consistent mental constructs when memory is faulty. Our results reveal several ways in which amnesia impacts distributed patterns of stimulus representation during encoding and retrieval.

Movement pattern biofeedback training after total knee arthroplasty: Randomized clinical trial protocol

IntroductionTotal knee arthroplasty (TKA) reduces joint symptoms, but habitual movement compensations persist years after surgery. Preliminary research on movement training interventions have signaled initial efficacy for remediating movement compensations and restoring knee joint loading symmetry during dynamic functional tasks after TKA. The purpose of this clinical trial is to determine if physical rehabilitation that includes movement training restores healthy movement patterns after TKA and reduces the risk of osteoarthritis (OA) progression in the contralateral knee. Methods/design150 participants will be enrolled into this randomized controlled trial. Participants will be randomly allocated to one of two dose-equivalent treatment groups: standard rehabilitation plus movement training (MOVE) or standard rehabilitation without movement training (CONTROL). Movement training will promote between-limb symmetry and surgical knee loading during activity-based exercises. Movement training strategies will include real-time biofeedback using in-shoe pressure sensors and verbal, visual, and tactile cues from the physical therapist. The primary outcome will be change in peak knee extension moment in the surgical knee during walking, from before surgery to six months after surgery. Secondary outcomes will include lower extremity movement symmetry during functional tasks, physical function, quadriceps strength, range of motion, satisfaction, adherence, contralateral knee OA progression, and incidence of contralateral TKA. DiscussionThis study will provide insights into the efficacy of movement training after unilateral TKA, along with mechanisms for optimizing long-term physical function and minimizing negative sequelae of compensatory movement patterns.

Perspectives on the prospective development of stroke-specific lower extremity wearable monitoring technology: a qualitative focus group study with physical therapists and individuals with stroke

BackgroundWearable activity monitors that track step count can increase the wearer’s physical activity and motivation but are infrequently designed for the slower gait speed and compensatory patterns after stroke. New and available technology may allow for the design of stroke-specific wearable monitoring devices, capable of detecting more than just step counts, which may enhance how rehabilitation is delivered. The objective of this study was to identify important considerations in the development of stroke-specific lower extremity wearable monitoring technology for rehabilitation, from the perspective of physical therapists and individuals with stroke.MethodsA qualitative research design with focus groups was used to collect data. Five focus groups were conducted, audio recorded, and transcribed verbatim. Data were analyzed using content analysis to generate overarching categories representing the stakeholder considerations for the development of stroke-specific wearable monitor technology for the lower extremity.ResultsA total of 17 physical therapists took part in four focus group discussions and three individuals with stroke participated in the fifth focus group. Our analysis identified four main categories for consideration: 1) ‘Variability’ described the heterogeneity of patient presentation, therapy approaches, and therapeutic goals that are taken into account for stroke rehabilitation; 2) ‘Context of use’ described the different settings and purposes for which stakeholders could foresee employing stroke-specific wearable technology; 3) ‘Crucial design features’ identified the measures, functions, and device characteristics that should be considered for incorporation into prospective technology to enhance uptake; and 4) ‘Barriers to adopting technology’ highlighted challenges, including personal attitudes and design flaws, that may limit the integration of current and future wearable monitoring technology into clinical practice.ConclusionsThe findings from this qualitative study suggest that the development of stroke-specific lower extremity wearable monitoring technology is viewed positively by physical therapists and individuals with stroke. While a single, specific device or function may not accommodate all the variable needs of therapists and their clients, it was agreed that wearable monitoring technology could enhance how physical therapists assess and treat their clients. Future wearable devices should be developed in consideration of the highlighted design features and potential barriers for uptake.

Shoulder Muscle Strength and Neuromuscular Activation 2 Years after Reverse Shoulder Prosthesis-An Experimental Case Control Study.

Although reverse shoulder arthroplasty (RSA) has shown successful postoperative outcomes, little is known about compensatory activation patterns of remaining shoulder muscles following RSA. The purpose of this experimental case control series was to investigate shoulder muscle strength and neuromuscular activation of deltoid and teres minor muscles 2 years after RSA. Humerus lengthening, center-of-rotation medialization, maximal voluntary strength, and electromyographic (EMG) activity were compared between the operated and the non-operated side of 13 patients (mean age: 73 years). Shoulder muscle strength was significantly lower on the operated side for external rotation (−54%), internal rotation (−20%), and adduction (−13%). Agonist deltoid EMG activity was lower on the operated side for shoulder flexion, extension, and internal and external rotation (p < 0.05). Antagonist deltoid coactivation was higher on the operated side for external rotation (p < 0.001). Large correlation coefficients were observed between shoulder adductor strength asymmetry and both center-of-rotation medialization (r = −0.73) and humerus lengthening (r = 0.71). Shoulder abduction strength and neuromuscular activation were well preserved 2 years after RSA, while persistent strength and activation deficits were observed for shoulder adduction and internal and external rotation. Additional studies are required to elucidate shoulder neuromuscular activation patterns before and after RSA to support decision making for surgical, implant design, and rehabilitation choices.

Functional Movement Screen Items Predict Dynamic Balance Under Military Torso Load.

Musculoskeletal injuries threaten military readiness and impose a significant financial burden. The functional movement screen (FMS), a 7-item, preparticipation screening tool, may aid in identifying compensatory movement patterns that can hinder physical performance and lead to injuries in active-duty military personnel. The primary aim of our study was to determine if items scores from the traditional FMS or a modified FMS (mFMS) obtained under loaded conditions can predict dynamic balance scores while wearing a military load. Thirty physically active adults (19 males and 11 females) who qualified for Army basic training completed unloaded and loaded FMS testing. Loaded balance was assessed using the Y balance test and the Biodex balance system. The mFMS and both loaded balance assessment protocols included a military load consisting of a standard issue rucksack (M.O.L.L.E.), kevlar helmet, and weighted vest (mass=24.2kg). mFMS item scores were significantly lower than FMS scores for six of the seven movement items. Both FMS and mFMS composite scores were correlated with Y balance scores (FMS: r=0.53, P=0.003; mFMS: r=0.37, P=0.043). Participants with higher composite scores (≥15) outperformed those with lower composite scores (≤14) for the FMS (P=0.006, d=1.16) and mFMS (P=0.031, d=0.75). Lasso penalized regression analyses revealed that (1) higher unloaded in-line lunge subscores predicted better Y balance scores, (2) loaded trunk stability push-up scores of three predicted worse balance on the Biodex, and (3) unloaded and loaded shoulder mobility scores of 3 predicted better performance on the Biodex balance system. The in-line lunge subscore from the FMS was the strongest predictor of torso-loaded balance, and the FMS may be more appropriate than a torso-loaded FMS battery when predicting torso-loaded balance among adults with body composition and fitness profiles similar to those of entering military recruits. These findings provide evidence supporting the use of the conventional FMS to identify active-duty personnel who exhibit greater balance deficits and may develop related musculoskeletal injuries while performing operational tasks that require the transport of heavy loads over long distances.

Reverse translation: effects of acclimation temperature and acute temperature challenges on oxygen consumption, diffusive water flux, net sodium loss rates, Q10 values and mass scaling coefficients in the rainbow trout (Oncorhynchus mykiss).

Our understanding is limited on how fish adjust the effective permeability of their branchial epithelium to ions and water while altering O2 uptake rate (MO2) with acute and chronic changes in temperature. We investigated the effects of acclimation temperature (8°C, 13°C and 18°C) and acute temperature challenges [acute rise (acclimated at 8°C, measured at 13°C and 18°C), acute drop (acclimated at 18°C, measured at 8°C and 13°C) and intermediate (acclimated at 13°C, measured at 8°C and 18°C)] on routine MO2, diffusive water flux, and net sodium loss rates in 24-h fasted rainbow trout (Oncorhynchus mykiss). In the temperature challenge tests, measurements were made during the first hour. In acclimated trout at all temperatures, allometric mass scaling coefficients were much higher for diffusive water flux than for MO2. Furthermore, the diffusive water flux rate was more responsive (overall Q10 = 2.75) compared to MO2 (Q10 = 1.80) over the 8-18°C range, and for both, Q10 values were greater at 8-13°C than at 13-18°C. The net Na+ flux rates were highly sensitive to acclimation temperature with an overall Q10 of 3.01 for 8-18°C. In contrast, very different patterns occurred in trout subjected to acute temperature challenges. The net Na+ flux rate was temperature-insensitive with a Q10 around 1.0. Both MO2 and diffusive water flux rates exhibited lower Q10 values than for the acclimated rates in response to either acute increases or decreases in temperature. These results fit Pattern 5 of Precht (undercompensation, reverse effect) and more precisely Pattern IIB of Prosser (reverse translation). These inverse compensatory patterns suggest that trout do not alter their rates very much when undergoing acute thermal challenges (diurnal fluctuations, migration through the thermocline). The greater changes seen with acclimation may be adaptive to long-term seasonal changes in temperature. We discuss the roles of aquaporins, spontaneous activity, and recent feeding in these responses.

Real-Time Detection of Compensatory Patterns in Patients With Stroke to Reduce Compensation During Robotic Rehabilitation Therapy.

Compensations are commonly employed by patients with stroke during rehabilitation without therapist supervision, leading to suboptimal recovery outcomes. This study investigated the feasibility of the real-time monitoring of compensation in patients with stroke by using pressure distribution data and machine learning algorithms. Whether trunk compensation can be reduced by combining the online detection of compensation and haptic feedback of a rehabilitation robot was also investigated. Six patients with stroke did three forms of reaching movements while pressure distribution data were recorded as Dataset1. A support vector machine (SVM) classifier was trained with features extracted from Dataset1. Then, two other patients with stroke performed reaching tasks, and the SVM classifier trained by Dataset1 was employed to classify the compensatory patterns online. Based on the real-time monitoring of compensation, a rehabilitation robot provided an assistive force to patients with stroke to reduce compensations. Good classification performance (F1 score > 0.95) was obtained in both offline and online compensation analysis using the SVM classifier and pressure distribution data of patients with stroke. Based on the real-time detection of compensatory patterns, the angles of trunk rotation, trunk lean-forward and trunk-scapula elevation decreased by 46.95%, 32.35% and 23.75%, respectively. High classification accuracies verified the feasibility of detecting compensation in patients with stroke based on pressure distribution data. Since the validity and reliability of the online detection of compensation has been verified, this classifier can be incorporated into a rehabilitation robot to reduce trunk compensations in patients with stroke.

Comparison of immediate effect of lateral wedge and uniform lift on the symmetry of weight-bearing during quiet stance and sit-to-stand activities among individuals with chronic stroke

CONTEXT: Following stroke, weight-bearing asymmetry during stance and functional activities may arise from the compensatory pattern of learned nonuse. AIMS: The aim of the study was to compare the immediate effect of lateral wedge and uniform lift under the foot of the nonparetic lower limb on the symmetry of weight-bearing in individuals with chronic stroke during quiet stance (QS) and sit-to-stand (STS) activities. SETTINGS AND DESIGN: This study was conducted in a physiotherapy department of a tertiary health-care setting and this was a cross-sectional experimental study. SUBJECTS AND METHODS: Convenience sampling method was used for this study. Eighty participants who fulfilled the study criteria were included in this study. The percentage of body weight borne by each leg was assessed using a force platform system during the activities of QS and STS during three conditions: Barefoot, ¼th inch lateral wedge and ¼th inch uniform lift under nonparetic lower limb. STATISTICAL ANALYSIS USED: Repeated-measures ANOVA and post hoc analysis were used for the statistical analysis. RESULTS: During QS activity, the percentage of weight-bearing improved significantly using lateral wedge and uniform lift (P CONCLUSIONS: Both lateral wedge and uniform lift were found to be equally effective in improving the symmetry of weight-bearing during QS activity. However, the introduction of lateral wedge or uniform lift had no significant improvement in weight-bearing symmetry during STS activity when compared with the barefoot.