17 research outputs found

    Still air resistance during walking and running

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    : In everyday life during terrestrial locomotion our body interacts with two media opposing the forward movement of the body: the ground and the air. Whereas the work done to overcome the ground reaction force has been extensively studied, the work done to overcome still air resistance has been only indirectly estimated by means of theoretical studies and by measurements of the force exerted on puppets simulating the geometry of the human body. In this study, we directly measured the force exerted by still air resistance on eight male subjects during walking and running on an instrumented treadmill with a belt moving at the same speed of a flow of laminar air facing the subject. Overall, the coefficient of proportionality between drag and velocity squared (Aeff) was smaller during running than walking. During running Aeff decreased progressively with increasing average velocity up to an apparently constant, velocity independent value, similar to that predicted in the literature using indirect methods. A predictive equation to estimate drag as a function of the speed and the height of the running subject is provided

    The bounce of the body in hopping, running and trotting: different machines with the same motor

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    The bouncing mechanism of human running is characterized by a shorter duration of the brake after ‘landing’ compared with a longer duration of the push before ‘takeoff’. This landing–takeoff asymmetry has been thought to be a consequence of the force–velocity relation of the muscle, resulting in a greater force exerted during stretching after landing and a lower force developed during shortening before takeoff. However, the asymmetric lever system of the human foot during stance may also be the cause. Here, we measure the landing–takeoff asymmetry in bouncing steps of running, hopping and trotting animals using diverse lever systems. We find that the duration of the push exceeds that of the brake in all the animals, indicating that the different lever systems comply with the basic property of muscle to resist stretching with a force greater than that developed during shortening. In addition, results show both the landing–takeoff asymmetry and the mass-specific vertical stiffness to be greater in small animals than in large animals. We suggest that the landing–takeoff asymmetry is an index of a lack of elasticity, which increases with increasing the role of muscle relative to that of tendon within muscle–tendon units

    Vision-related quality of life and symptom perception change over time in newly-diagnosed primary open angle glaucoma patients.

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    To evaluate the change over time of vision-related quality of life (QoL) and glaucoma symptoms in a population of newly-diagnosed primary open angle glaucoma (POAG) patients. Multicenter, prospective study. Consecutive newly-diagnosed POAG patients were enrolled and followed-up for one year. Follow-up visits were scheduled at 6 and 12 months from baseline. At each visit, vision-related QoL and glaucoma-related symptoms were assessed by the means of the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and the Glaucoma Symptom Scale (GSS), respectively. Trends over time for NEI-VFQ-25 and GSS scores were evaluated with longitudinal linear mixed models. One-hundred seventy-eight patients were included in the analysis. At baseline, early to moderate glaucoma stages were associated with higher scores for most GSS and NEI-VFQ-25 items, while lower best-corrected visual acuity was associated with lower scores for 4 of the 12 NEI-VFQ-25 items. During the follow-up, all the GSS scores, the NEI-VFQ-25 total score, and 7 of the 12 NEI-VFQ-25 scores significantly improved (p < 0.05). In multivariate model, higher increases of most GSS and NEI-VFQ-25 scores were modeled in patients with low scores at baseline. Vision-related QoL and glaucoma-related symptom perception significantly improved during the one-year follow-up in this population of newly diagnosed POAG patients

    Minkowski4×S2 solutions of IIB supergravity

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    We classify urn:x-wiley:00158208:media:prop201800006:prop201800006-math-0002 Minkowski4 solutions of IIB supergravity with an urn:x-wiley:00158208:media:prop201800006:prop201800006-math-0003 symmetry geometrically realized by an S2‐foliation in the remaining six dimensions. For the various cases of the classification, we reduce the supersymmetric system of equations to PDEs. These cases often accommodate systems of intersecting branes and half‐maximally supersymmetric AdS5, 6, 7 solutions when they exist. As an example, we analyze the AdS6 case in more detail, reducing the supersymmetry equations to a single cylindrical Laplace equation. We also recover an already known linear dilaton background dual to the (1, 1) Little String Theory (LST) living on NS5‐branes, and we find a new Minkowski5 linear dilaton solution from brane intersections. Finally, we also discuss some simple Minkowski4 solutions based on compact conformal Calabi‐Yau manifolds

    Old men running: Mechanical work and elastic bounce

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    It is known that muscular force is reduced in old age. We investigate what are the effects of this phenomenon on the mechanics of running. We hypothesized that the deficit in force would result in a lower push, causing reduced amplitude of the vertical oscillation, with smaller elastic energy storage and increased step frequency. To test this hypothesis, we measured the mechanical energy of the centre of mass of the body during running in old and young subjects. The amplitude of the oscillation is indeed reduced in the old subjects, resulting in an approximately 20% smaller elastic recovery and a greater step frequency (3.7 versus 2.8Hz, p=1.9×10-5, at 15-17kmh-1). Interestingly, the greater step frequency is due to a lower aerial time, and not to a greater natural frequency of the system, which is similar in old and young subjects (3.6 versus 3.4Hz, p=0.2). Moreover, we find that in the old subjects, the step frequency is always similar to the natural frequency, even at the highest speeds. This is at variance with young subjects who adopt a step frequency lower than the natural frequency at high speeds, to contain the aerobic energy expenditure. Finally, the external work to maintain the motion of the centre of mass is reduced in the old subjects (0.9 versus 1.2Jkg-1m-1, p=5.1×10-6) due to the lower work done against gravity, but the higher step frequency involves a greater internal work to reset the limbs at each step. The net result is that the total work increases with speed more steeply in the old subjects than in young subjects. © 2007 The Royal Society

    Minkowski Solutions of IIB Supergravity

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    We classify Minkowski4 solutions of IIB supergravity with an symmetry geometrically realized by an S2-foliation in the remaining six dimensions. For the various cases of the classification, we reduce the supersymmetric system of equations to PDEs. These cases often accommodate systems of intersecting branes and half-maximally supersymmetric AdS5, 6, 7 solutions when they exist. As an example, we analyze the AdS6 case in more detail, reducing the supersymmetry equations to a single cylindrical Laplace equation. We also recover an already known linear dilaton background dual to the (1, 1) Little String Theory (LST) living on NS5-branes, and we find a new Minkowski5 linear dilaton solution from brane intersections. Finally, we also discuss some simple Minkowski4 solutions based on compact conformal Calabi-Yau manifolds

    A comparison between the administration of oral prolonged-release oxycodone-naloxone and transdermal fentanyl in patients with moderate-to-severe cancer pain: a propensity score analysis

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    A Roberto,1 MT Greco,2 L Legramandi,3 F Galli,3 M Galli,4 O Corli1 1Pain and Palliative Care Research Unit, Oncology Department, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy, 2Department of Clinical Sciences and Community, University of Milan, Milan, Italy, 3Methodology for Clinical Research Laboratory, Oncology Department, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy, 4Scientific Medical Communication srl, Novara, Italy Background: Opioids are the most important pharmacological treatment for moderate-to-severe cancer pain, but side effects limit their use. Transdermal fentanyl (TDF) and oral prolonged-release oxycodone-naloxone (OXN-PR) are effective in controlling chronic pain, with less constipation compared to other opioids. However, TDF and OXN-PR have never been directly compared.Patients and methods: Cancer patients with moderate-to-severe chronic pain were consecutively enrolled in two prospective 28-day trials, received either TDF or OXN-PR, and were assessed at baseline and after 7, 14, 21, and 28 days. The primary endpoint was 28-day analgesic response rate (average pain intensity decrease ≥30% from baseline). Other outcome measures included opioid daily dose changes over time; need for adjuvant analgesics; number of switches; premature discontinuation; presence and severity of constipation; and other adverse drug reactions. To compare the efficacy and the safety of TDF and OXN-PR, we used the propensity score analysis to adjust for heterogeneity between the two patient groups.Results: Three hundred ten out of 336 patients originally treated (119 TDF and 191 OXN-PR) were included in the comparative analysis. The amount of responders was comparable after TDF (75.3%) and OXN-PR administration (82.9%, not significant [NS]). The final opioid daily dose expressed as morphine equivalent was 113.6 mg for TDF and 44.5 mg for OXN-PR (p<0.0001). A daily opioid dose escalation >5% was less common after OXN-PR (19.3%) than after TDS administration (37.9%, p<0.0001). Opioid switches and discontinuation were similar in both groups. Severe constipation in the two groups was comparable (32.6% after TDF vs 24.7% after OXN-PR, NS). Nausea, vomiting, and dry mouth were significantly less frequent in the OXN-PR group than in the TDF group.Conclusion: Despite a similar analgesic activity in moderate-to-severe cancer pain, OXN-PR is characterized by lower daily dosages, less need for drug escalation, and fewer side effects compared to TDF. Keywords: opioid induced constipation, oxycodone-naloxone, transdermal fentanyl, propensity score, analgesic efficacy, constipatio

    Design and Gamification for Reshaping Relations and Services in Social Cooperatives

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    It’s increasingly clear that design is no longer just an added value for business in contributing to developing better products, services and experiences; instead, it’s leading a new methodology in managing the process of innovation. In social cooperatives, design thinking is providing possibilities to better organize complex internal relationships in order to facilitate innovation process towards better services as final offerings. The research team of Creative Industries lab is collaborating with a national organization with local structures for social and health care. This type of organizations is generally not considered within design-related fields, however, it's necessary to show up possible impacts and values of design for them. Thus, the research activities and intervention are aiming at supporting the organization in improving the quality and effectiveness of its offered services through reshaping the development approach and transforming the organization from results-oriented to capability-oriented. The research has developed a gamificated co-design activity involved all the staffs of the organization as a “pilot” to test a new way to form organizational change. It had two specific objectives: the primary activity is to involve all the staffs in improving the sense of belonging and working motivation; the latter one is to develop a new strategy to facilitate care workers to participate in service innovation process, which is supported by specific designed toolkits

    Still air resistance dataset from Still air resistance during walking and running

    No full text
    In everyday life during terrestrial locomotion our body interacts with two media opposing the forward movement of the body: the ground and the air. Whereas the work done to overcome the ground reaction force has been extensively studied, the work done to overcome still air resistance has been only indirectly estimated by means of theoretical studies and by measurements of the force exerted on puppets simulating the geometry of the human body. In this study, we directly measured the force exerted by still air resistance on eight male subjects during walking and running on an instrumented treadmill with a belt moving at the same speed of a flow of laminar air facing the subject. Overall, the coefficient of proportionality between drag and velocity squared (Aeff) was smaller during running than walking. During running Aeff decreased progressively with increasing average velocity up to an apparently constant, velocity independent value, similar to that predicted in the literature using indirect methods. A predictive equation to estimate drag as a function of the speed and the height of the running subject is provided

    Metronomic Chemotherapy in Triple-Negative Metastatic Breast Cancer: The Future Is Now?

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    Triple-negative breast cancer (TNBC) shows a very bad prognosis, even in early stages of disease. Metronomic chemotherapy refers to the minimum biologically effective dose of a chemotherapy agent given as a continuous dosing regimen with no prolonged drug-free breaks that leads to antitumor activity. In the present article, we review preclinical and clinical data of metronomic administration of chemotherapy agents with or without biological agents in TNBC cell lines and patients, contextually reporting data from the VICTOR-2 study in the subgroup of patients with TNBC, in order to stimulate new ideas for the design of clinical trials in this subset of patients
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