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We examine the role that randomness or noise in individual motion may play in forming effective grazing strategies for herd members as they collectively move toward a destination. Through a model where animals are attracted to Voronoi neighbors as well as a destination endpoint, we show that including a significant random motion component can speed up the movement of a herd toward this destination, increase the efficiency that food is acquired during the travel, and facilitate a natural herd shape that mitigates predation risk. Specifically, if the influence of the Voronoi neighbors on individual motion is equal to the pull toward the destination, we find that optimal travel time and food consumption efficiency occurs for noise approximately twice as strong as the influence of herd members to each other, in a range of herd sizes from 10 to 100. We find that reducing the destination influence lowers this optimal noise only slightly, with random motion still exceeding the influence of neighbors. For a destination influence exceeding that of the Voronoi neighbors, an additional travel mode appears with minimal noise and aligned velocities in which the herd marches directly toward the endpoint. Our results are consistent with observational evidence of random motion in several animal groups, and motivate its generalization to traveling and grazing herds., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Neck pain (NP) is disabling and costly., Objectives: To assess the effectiveness of exercise on pain, disability, function, patient satisfaction, quality of life (QoL) and global perceived effect (GPE) in adults with NP., Methods: We searched computerised databases up to May 2014 for randomized controlled trials (RCTs) comparing exercise to a control in adults with NP with/without cervicogenic headache (CGH) or radiculopathy. Two reviewers independently conducted selection, data abstraction and assessed risk of bias. Meta-analyses were performed to establish pooled standardised mean differences (SMDp). The Grade of Recommendation, Assessment, Development and Evaluation (GRADE) was used to summarise the body of evidence., Main Results: The following exercises (27 trials) were supported by 'Moderate GRADE' evidence: For chronic NP, 1) cervico-scapulothoracic and upper extremity (UE) strengthening for moderate to large pain reduction immediately post treatment (IP) and at short-term (ST) follow-up; 2) scapulothoracic and UE endurance training for a small pain reduction (IP/ST); 3) cervical, shoulder and scapulothoracic strengthening and stretching exercise for a small to large pain reduction in the long-term (LT) (SMDp -0.45 [95%CI: -0.72 to -0.18]) and function improvement; 4) cervico-scapulothoracic strengthening/stabilisation exercises for pain and function at intermediate-term (IT) (SMDp -14.90 [95%CI: -22.40 to -7.39]). 5) mindfulness exercises (Qigong) for minor improved function but not GPE (ST). For chronic CGH, cervico-scapulothoracic strengthening and endurance exercises including pressure biofeedback for small/moderate improvement of pain, function and GPE (IP/LT)., Authors' Conclusions: Specific strengthening exercises of the neck, scapulothoracic and shoulder for chronic NP and chronic CGH are beneficial. Future research should explore optimal dosage., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Purpose: An evidence-based clinical practice guideline was developed to ascertain the risks and benefits for manipulation or mobilization in treating mechanical neck disorders with or without radicular findings or cerviogenic headache. Pain, function, patient satisfaction and adverse events were appraised., Methods: The practice guideline development cycle/model and Cochrane reviewing process, critiquing past reviews, randomized trials and surveys were used., Results: Manipulation and mobilization alone showed similar effects as placebo, wait period, or control group, and appeared similar in benefit for pain relief. While high-technology exercises were superior to manipulation alone for improving long-term pain scores, manipulation plus low-technology exercise had the same effect. Patient satisfaction scores favoured manipulation plus low-technology exercise over manipulation alone, and high-technology exercise alone. Multi-modal care including some combination of manipulation or mobilizations and exercise was superior to control, other physical medicine methods, and rest. Based on weak evidence, estimates for serious complication for manipulation ranged from one in 20,000 to five in 10,000,000., Recommendations: Stronger evidence suggests a multi-modal management strategy using mobilization or manipulation plus exercise is beneficial for relief of mechanical neck pain. Weaker evidence suggest less benefit to either manipulation/mobilization done alone than when used with exercise. The risk rate is uncertain.