748 research outputs found

    Inertial Sensors in Swimming: Detection of Stroke Phases through 3D Wrist Trajectory.

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    Monitoring the upper arm propulsion is a crucial task for swimmer performance. The swimmer indeed can produce displacement of the body by modulating the upper limb kinematics. The present study proposes an approach for automatically recognize all stroke phases through three-dimensional (3D) wrist\u2019s trajectory estimated using inertial devices. Inertial data of 14 national-level male swimmer were collected while they performed 25 m front-crawl trial at intensity range from 75% to 100% of their 25 m maximal velocity. The 3D coordinates of the wrist were computed using the inertial sensors orientation and considering the kinematic chain of the upper arm biomechanical model. An algorithm that automatically estimates the duration of entry, pull, push, and recovery phases result from the 3D wrist\u2019s trajectory was tested using the bi-dimensional (2D) video-based systems as temporal reference system. A very large correlation (r = 0.87), low bias (0.8%), and reasonable Root Mean Square error (2.9%) for the stroke phases duration were observed using inertial devices versus 2D video-based system methods. The 95% limits of agreement (LoA) for each stroke phase duration were always lower than 7.7% of cycle duration. The mean values of entry, pull, push and recovery phases duration in percentage of the complete cycle detected using 3D wrist\u2019s trajectory using inertial devices were 34.7 (\ub1 6.8)%, 22.4 (\ub1 5.8)%, 14.2 (\ub1 4.4)%, 28.4 (\ub1 4.5)%. The swimmer\u2019s velocity and arm coordination model do not affect the performance of the algorithm in stroke phases detection. The 3D wrist trajectory can be used for an accurate and complete identification of the stroke phases in front crawl using inertial sensors. Results indicated the inertial sensor device technology as a viable option for swimming arm-stroke phase assessment

    Acute effects of a high volume vs. High intensity bench press protocol on electromechanical delay and muscle morphology in recreationally trained women

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    The purpose of the present investigation was to compare the acute responses on muscle architecture, electromechanical delay (EMD) and performance following a high volume (HV: 5 sets of 10 reps at 70% of 1 repetition maximum (1RM)) and a high intensity (HI: 5 sets of 3 reps at 90% of 1RM) bench press protocol in women. Eleven recreationally trained women (age = 23.3 ± 1.8 y; body weight = 59.7 ± 6.0 kg; height = 164.0 ± 6.3 cm) performed each protocol in a counterbalanced randomized order. Muscle thickness of pectoral (PEC MT) and triceps muscles (TR MT) were collected prior to and 15 min post each trial. In addition, EMD of pectoral (PEC EMD) and triceps (TR EMD) muscles were calculated during isometric bench press maximum force tests performed at the same timepoints (IBPF). Significantly greater increases in PEC MT (p < 0.001) and TR MT (p < 0.001) were detected following HV compared to HI. PEC EMD showed a significantly greater increase following HV compared to HI (p = 0.039). Results of the present study indicate that the HV bench press protocol results in greater acute morphological and neuromuscular changes compared to a HI protocol in women. Evaluations of muscle morphology and electromechanical delay appear more sensitive to fatigue than maximum isometric force assessments

    Produzioni di eccellenza: un caso di successo

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    In questo capitolo si presenta il caso di un produttore di cravatte artigianali che è stato in grado di valo-rizzare la storia e il background di partenza, e se ne evidenziano le implicazioni principali, sottolineando l’importanza della memoria come asset strategico per la formazione di un’identità organizzativa. Questo capitolo si concentra dunque su un produttore artigianale di cravatte localizzato nella città di Napoli: E. Marinella. Il caso è stato scelto in quanto rappresenta ai nostri occhi un esempio virtuoso di valorizzazione della tradizione locale e della propria storia aziendale. Grazie alla valorizzazione della propria tradizione E. Marinella è riuscita infatti a posizionarsi come un marchio di lusso, apprezzato per la manifattura artigianale e l’unicità della propria collezione

    Does visual cortex lactate increase following photic stimulation in migraine without aura patients? A functional 1H-MRS study

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    Proton magnetic resonance spectroscopy (1H-MRS) has been used in a number of studies to assess noninvasively the temporal changes of lactate (Lac) in the activated human brain. Migraine neurobiology involves lack of cortical habituation to repetitive stimuli and a mitochondrial component has been put forward. Our group has recently demonstrated a reduction in the high-energy phosphates adenosine triphosphate (ATP) and phosphocreatine (PCr) in the occipital lobe of migraine without aura (MwoA) patients, at least in a subgroup, in a phosphorus MRS (31P-MRS) study. In previous studies, basal Lac levels or photic stimulation (PS)-induced Lac levels were found to be increased in patients with migraine with aura (MwA) and migraine patients with visual symptoms and paraesthesia, paresia and/or dysphasia, respectively. The aim of this study was to perform functional 1H-MRS at 3 T in 20 MwoA patients and 20 control subjects. Repetitive visual stimulation was applied using MR-compatible goggles with 8 Hz checkerboard stimulation during 12 min. We did not observe any significant differences in signal integrals, ratios and absolute metabolite concentrations, including Lac, between MwoA patients and controls before PS. Lac also did not increase significantly during and following PS, both for MwoA patients and controls. Subtle Lac changes, smaller than the sensitivity threshold (i.e. estimated at 0.1–0.2 μmol/g at 3 T), cannot be detected by MRS. Our study does, however, argue against a significant switch to non-aerobic glucose metabolism during long-lasting PS of the visual cortex in MwoA patients

    Crafting social memory for international recognition: the role of place and tradition in an Italian silk-tie maker

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    This chapter focuses on the role of place and local history in building the brand identities of craft organizations. Recent research on craft organizations has focused on the local context as an important factor for identity recognition and distinctiveness. However, an important but understudied aspect of this relates to the organizational use of both the sense of place and history and how visions of the past are used to support and legitimate organizational operations. In this context, local history is not simply regarded as a timeline along which events come to pass, but as a symbolic and cultural artefact that organizational actors deliberately manage and construct

    Maximizing Tissue Contrast for MRI Evaluation of Parkinson’s Disease

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    Wolbachia, doxycycline and macrocyclic lactones: New prospects in the treatment of canine heartworm disease

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    Abstract Melarsomine dihydrochloride (Immiticide®, Merial) is the only approved adulticidal drug for the treatment of canine heartworm disease (HWD). However, in cases where arsenical therapy is not possible or is contraindicated, a monthly heartworm preventive along with doxycycline for a 4-week period, which targets the bacterial endosymbiont Wolbachia, might be considered. There are published reports on the efficacy of ivermectin and doxycycline in both experimentally and naturally infected dogs, but no data on the use of other macrocyclic lactones (MLs) with a similar treatment regime. Preliminary results of studies in dogs show that a topical formulation of moxidectin, the only ML currently registered as a microfilaricide, is also adulticidal when combined with doxycycline. It is not yet known if the efficacy of these combination therapies is due to pharmacokinetic synergism. A recent study showed that serum levels of doxycycline in dogs treated with the combination protocol were not statistically different compared to dogs treated with doxycycline alone. However, lungs from dogs treated with the combination therapy showed a marked reduction in T regulatory cells, indicating that treatment efficacy may be due to a heightened immune response against the parasite. Further studies are necessary to evaluate the long-term clinical outcome of combination protocols and to establish the most efficient treatment for HWD in dogs

    Evaluation of a rapid immunochromatographic test for the detection of low burden Dirofilaria immitis (heartworm) in dogs and cats

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    The performance of a rapid immunochromatographic test for the detection of Dirofilaria immitis antigens (Speed Diro (TM); BVT-Virbac, France) was assessed in 49 experimentally infected dogs and in 244 naturally infected animals; 142 dogs and 102 cats. In experimentally infected dogs, Speed Diro (TM) showed a sensitivity of 90.9% in dogs infected with one adult female worm and 100% in dogs infected with more than one female worm. Specificity was 100%. For naturally infected dogs, the Knott test and PetChek(A (R)) HTWM PF served as reference methods for microfilaremia and antigenemia, respectively. All microfilaemic dogs (55/142) were positive with Speed Diro (TM). Importantly, none of the 21 dogs infected with D. repens were positive. The results of Speed Diro (TM) for the detection of antigenemia were compared with two in-house tests, SNAP(A (R)) HTWM and Witness(A (R)) Dirofilaria, and all three tests were 100% specific and sensitive in comparison to PetChek(A (R)) HTWM PF. For the evaluation of feline samples, 102 cats were examined by echocardiography. Sera from 87 heartworm-infected cats were tested by Speed Diro (TM) and SNAP(A (R)) HTWM. The results of Speed Diro (TM) were equivalent to SNAP(A (R)) HTWM, with a sensitivity of 98.9% and a specificity of 100%
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