Full Running Research Articles

138 Myocardial Fibrosis in Marathon Athletes: A Marker of Occult Coronary Artery Disease

Several studies have correlated elevations in cardiac biomarkers of injury post marathon with transient and reversible right ventricular (RV) systolic dysfunction as assessed by both transthoracic echocardiography (TTE) and cardiac MRI (CMR). Whether or not permanent myocardial injury occurs due to repeated marathon running in the aging population remains controversial. To assess the extent and severity of cardiac dysfunction after the completion of full marathon running in individuals greater than 50 years of age using cardiac biomarkers, TTE, cardiac computed tomography (CCT), and CMR. A total of 25 healthy volunteers (21 males, 55±4 years old) from the 2010 and 2011 Manitoba Full Marathons (26.2 miles) were included in the study. Cardiac biomarkers and TTE were performed one week prior to the marathon, immediately after completing the race and at one-week follow-up. CMR was performed at baseline and within 24 hours of completion of the marathon, followed by CCT within 3 months of the marathon. All participants demonstrated an elevated cTnT post marathon. Right atrial and ventricular volumes increased, while RV systolic function decreased significantly immediately post marathon, returning to baseline values one week later. Of the entire study population, only two individuals demonstrated delayed enhancement of the subendocardium in the anterior wall of the left ventricle, with evidence of stenosis of the left anterior descending artery on CCT (Figure 1). The presence of myocardial fibrosis in marathon athletes is not due to repeated stress from endurance running, but may be a marker of occult coronary artery disease. (Figure 1).

Non‐destructive subsurface damage monitoring in bearings failure mode using fractal dimension analysis

PurposeBearings in field applications with high dynamic loading, e.g. wind energy plants, suffer from sudden failure initiated by subsurface material transformation, known as white etching cracks in a typical scale of μm, preferably around the maximum Hertzian stress zone. Despite many investigations in this field no precise knowledge about the root cause of those failures is available, due to the fact that failure under real service conditions of wind energy plants differs from what is known from test rig results in terms of contact loading, lubrication or dynamics. The purpose of this paper is to apply Barkhausen noise measurement to a full bearing test ring running under conditions of elastohydrodynamic lubrication (EHL) with high radial preload.Design/methodology/approachFull bearing tests are carried out by use of DGBB (Deep Grove Ball Bearings) with 6206 specification, material set constant as 100Cr6, martensitic hardening, 10‐12 percent maximum retained austenite and radial preload of 3500 MPa. Speed is set 9000 rpm, temperature is self setting at 80°C by test conditions. For tests, synthetic hydrocarbon base oil (Poly‐α‐Olefine) with a 1 percent amount of molydenum‐dithiophosphate (organic chain given as 2‐ethylhexyl) was used.FindingsNon‐destructive fractal dimension analyses by use of Barkhausen noise measurements is of versatile value in terms of recording bearing manufacturing processes, but can also be part of non‐destructive condition monitoring of bearings in field applications, where predictive reactive maintenance is crucial for availability of the plant.Research limitations/implicationsBarkhausen noise signal recording may also be valuable for case studies related to microstructure changes of steel under operation conditions. Bearings are exposed in plenty of conditions to phenomena such as straying currents, subsequently straying magnetic fields. Hardly anything is known about how microstructure of bearing steel is susceptible to such conditions. This will be part of further studies.Originality/valueResults given in the paper show that sudden bearing failure, according to formation of subsurface material property changes might be driven by activities of dislocations. Since those activities start with sequences of stress field‐induced formation of domains, later by formation of low‐angle subgrains, and at least phase transformation, recording of the Barkhausen signal would lead to real predictive condition monitoring in applications where a highly dynamic loading of the contact, even with low nominal contact pressure leads to sudden failure induced by white etching.

Exercise protects against MPTP-induced neurotoxicity in mice

Exercise has been shown to be potently neuroprotective in several neurodegenerative models, including 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) model of Parkinson's disease (PD). In order to determine the critical duration of exercise necessary for DA neuroprotection, mice were allowed to run for either 1, 2 or 3 months prior to treatment with saline or MPTP. Quantification of DA neurons in the SNpc show that mice allowed to run unrestricted for 1 or 2 months lost significant numbers of neurons following MPTP administration as compared to saline treated mice; however, 3 months of exercise provided complete protection against MPTP-induced neurotoxicity. To determine the critical intensity of exercise for DA neuroprotection, mice were restricted in their running to either 1/3 or 2/3 that of the full running group for 3 months prior to treatment with saline or MPTP. Quantification of DA neurons in the SNpc show that mice whose running was restricted lost significant numbers of DA neurons due to MPTP toxicity; however, the 2/3 running group demonstrated partial protection. Neurochemical analyses of DA and its metabolites DOPAC and HVA show that exercise also functionally protects neurons from MPTP-induced neurotoxicity. Proteomic analysis of SN and STR tissues indicates that 3 months of exercise induces changes in proteins related to energy regulation, cellular metabolism, the cytoskeleton, and intracellular signaling events. Taken together, these data indicate that exercise potently protects DA neurons from acute MPTP toxicity, suggesting that this simple lifestyle element may also confer significant protection against developing PD in humans.

Study on the Difference of the Maneuvering Characteristics of a VLCC in Standstill from those of her in Running

The objective of this paper is to make clear the difference of maneuvering characteristics of a VLCC in standstill from those of her in running. The authors made mathematic models to calculate maneuvering motions of a VLCC in standstill using various ahead engine with full rudder angle and calculated their motions in each case and compared the calculated values with those of the same vessel running in sea trial tests. The difference of motions between them is great. For example, a VLCC in standstill can achieve a great alteration of heading over 90 degrees within the distance of 0.2L advance while she advances 3.0L for 90 degrees turning in full running sea trial turning test. Therefore whenever a VLCC in standstill meets a vessel approaching in collision course situation in near distance, it is better and recommendable that she should use her ahead engine with full rudder to avoid collision. So "maneuvering trial tests in standstill conditions" should be added to the content of sea trial tests when a newly built VLCC commence to take sea trials, that has not been included until now.

Trusted virtual platforms

This paper introduces our work around combining machine virtualization technology with Trusted Computing Group technology. We first describe our architecture for reducing and containing the privileged code of the Xen Hypervisor. Secondly we describe our Trusted Virtual Platform architecture. This is aimed at supporting the strong enforcement of integrity and security policy controls over a virtual entity where a virtual entity can be either a full guest operating system or virtual appliance running on a virtualized platform. The architecture includes a virtualization-specific integrity measurement and reporting framework. This is designed to reflect all the dependencies of the virtual environment of a guest operating system. The work is a core enabling component of our research around converged devices -- client platforms such as notebooks or desktop PCs that can safely host multiple virtual operating systems and virtual appliances concurrently and report accurately on the trustworthiness of the individually executing entities.

Solar and atmospheric neutrinos in Super-Kamiokande

The Super-Kamiokande (SK) water Cherenkov detector has been operating for nearly 12 years collecting data for the study of both solar and atmospheric neutrinos as well as searching for neutrinos from supernovæ (and relic supernovæ) and for nucleon decay. The experiment has undergone three operating phases during the full running period: SK-I (40% photocathode coverage), SK-II (20% coverage), and SK-III (40% coverage). Soon, the experiment will move into its fourth phase when the data acquisition electronics are upgraded in late 2008. Presented here are neutrino oscillation results from SK-I and SK-II solar and atmospheric data, and a preliminary look at data from SK-III. Also discussed briefly is the upcoming electronics upgrade that will carry the experiment into its fourth phase.

Experimental Observation of Fluxon Diffusion in Josephson Rings

We present switching current measurements in niobium-aluminum oxide-niobium underdamped Josephson rings. Underdamped Josephson rings display hysteretic current-voltage curves which can be characterized by their switching current, the value of applied current at which the junctions switch to the energy-gap voltage. The value of the switching current is strongly affected by temperature and by the presence of fluxons in the system. We observe a very small voltage (∼400 nV) across the ring prior to switching, indicating a low-velocity fluxon diffusion state before the jump to a full running state. In analogy with previous work on single junctions, we analyze the switching current data with the process of thermal activation over a dissipation barrier, where the system switches from a low velocity state to a high velocity state. We find that our data agrees qualitatively with this description, further supporting the observation of fluxon diffusion.

‘Working Out’ Identity: Distance Runners and the Management of Disrupted Identity

This article contributes fresh perspectives to the empirical literature on the sociology of the body, and of leisure and identity, by analysing the impact of long‐term injury on the identities of two amateur but serious middle/long‐distance runners. Employing a symbolic interactionist framework, and utilising data derived from a collaborative autoethnographic project, it explores the role of ‘identity work’ in providing continuity of identity during the liminality of long‐term injury and rehabilitation, which poses a fundamental challenge to athletic identity. Specifically, the analysis applies Snow and Anderson’s (1995) and Perinbanayagam’s (2000) theoretical conceptualisations in order to examine the various forms of identity work undertaken by the injured participants, along the dimensions of materialistic, associative and vocabularic identifications. Such identity work was found to be crucial in sustaining a credible sporting identity in the face of disruption to the running self, and in generating momentum towards the goal of restitution to full running fitness and re‐engagement with a cherished form of leisure.

Prospects to search for E6 isosinglet quarks in ATLAS

We consider pair production of new down-type isosinglet quarks originating from E6, which is the favorite gauge symmetry group in superstring inspired GUT models. The study concentrates on the possibility of observing the pair production of the lightest of the new quarks, D, in the ATLAS detector at the forthcoming LHC accelerator, in the channel DD̄→ZjZj . Both signal and background events are studied using tree level event generators based on Monte Carlo techniques. The detector effects are taken into account using the ATLAS fast simulation tool. It is shown that ATLAS can observe the D quark within the first year of low luminosity LHC operation if its mass is less than 650 GeV. For the case of two years of full luminosity running, 1 TeV can be reached with about three sigma significance.

High energy efficiency test system for induction heating generators

Power supplies used in induction heating industrial applications must be entirely tested after its manufacturing in order to assure its security and reliability by means of a full power running test of several hours of duration. Nowadays this test is done with a dissipative load which implies a large waste of energy. This paper proposes a new high efficiency test system for induction heating generators. It incorporates a regenerative electronic load which allows an extraordinary improvement of the efficiency of this test with an important economical and ecological benefit.

Search for neutrinoless double beta decay with enriched 76Ge in Gran Sasso 1990–2003

The results of the HEIDELBERG–MOSCOW experiment which searches with 11 kg of enriched 76Ge for double beta decay in the Gran Sasso underground laboratory are presented for the full running period August 1990–May 2003. The duty cycle of the experiment was ∼80%, the collected statistics is 71.7 kgyr. The background achieved in the energy region of the Q value for double beta decay is 0.11 eventskg−1yr−1 keV−1. The two-neutrino accompanied half-life is determined on the basis of more than 100000 events. The confidence level for the neutrinoless signal has been improved to 4.2σ.

HEEL PAIN IN A RUNNER

HISTORY - A 40-year old female collegiate softball coach initially developed lateral pain of the left heel after landing hard on her heel while playing softball. She continued her normal running routine as she was at the time training for a marathon and the heel pain subsided over 2–3 weeks. The heel recieved a second blow approximately 2 months later and the subsequent pain did not resolve despite a short period of rest from running. The patient resumed her running program despite the heel pain. The pain was located at the inferior-lateral aspect of the heel and was worse when rising in the morning and at the initiation of a run. She was able to continue her training despite increasing pain and participated in the marathon 5 months after the initial occurence. She was initially treated for peroneal tendonitis and plantar fascitis unsuccessfully during this period leading up to the marathon. PHYSICAL EXAMINATION - Examination at the initial office visit approximately one month prior to the marathon revealed tenderness at the distal peroneal tendon inferior to the lateral malleolus and at the inferior-lateral aspect of the calcaneus. The foot and ankle had full range of motion and strength with pain produced in passive inversion only. There was a palpable click noted along the peroneal tendons with active eversion and full weight-bearing produced lateral heel pain. At a subsequent office visit one month after the marathon, the pain and click along the peroneal tendon had resolved. The pain at the inferior-lateral aspect of the calcaneus remained and medial/lateral compression of the calcaneus produced pain. DIFFERENTIAL DIAGNOSIS Plantar fascitis Fat pad syndrome Calcaneal contusion Calcaneal stress fracture Peroneal tendonitis TEST AND RESULTS Inital Office Radiographs:- No bony pathology.Bone scan of lower extremities one month after marathon:- focus of moderately intense increased radiotracer uptake seen in posterior aspect of left calcaneus.Gait analysis done during rehabilitation process:- Pattern of rearfoot varus with lateral heel strike and forefoot valgus with mild pronation. FINAL/WORKING DIAGNOSIS Stress fracture of posterior aspect of left calcaneus TREATMENT Full non-weight bearing with Aircast walking boot and crutches for 3 weeks. Partial weight bearing for additional 3 weeks Physical therapy after return to weight bearing with iontophoresis, gastroc and plantar fascia stretching and progressive strengthening. Gait analysis and custom orthotics Return to activities as dictated by pain and return to full running in 4–6 months.

Bone mass in the calcaneus after heavy loaded eccentric calf-muscle training in recreational athletes with chronic achilles tendinosis.

In an ongoing prospective study of 14 recreational athletes (12 males and 2 females, mean age 44.2 +/- 7.1 years) with unilateral chronic Achilles tendinosis, we investigated the effect of treatment with heavy-loaded eccentric calf-muscle training. Pain during activity (recorded on a VAS scale) and isokinetic concentric and eccentric calf-muscle strength (peak torque at 90 degrees /second and 225 degrees /second) on the injured and noninjured side were evaluated. In this group of patients, we examined areal bone mineral density (BMD) of the calcaneus after 9 months (range 6-14 months) of training. BMD of the injured side (subjected to heavy-loaded eccentric training) was compared with BMD of the noninjured side. Before onset of heavy-loaded eccentric training, all patients had Achilles tendon pain which prohibited running activity, and significantly lower concentric and eccentric plantar flexion peak torque on the injured compared with the noninjured side. The training program consisted of 12 weeks of daily, heavy-loaded, eccentric calf-muscle training; thereafter the training was continued for 2-3 days/week. The clinical results were excellent-all 14 patients were back at their preinjury level with full running activity at the 3 month follow-up. The concentric and eccentric plantar flexion peak torque had increased significantly and did not significantly differ from the noninjured side at the 3 and 9 month follow-up. There were no significant side-to-side differences in BMD of the calcaneus. There was no significant relationship between BMD of the calcaneus and calf-muscle strength. As a comparison group, we used 10 recreational athletes (5 males and 5 females) mean age 40.9 years (range 26-55 years), who were selected for surgical treatment of chronic Achilles tendinosis localized at the 2-6 cm level. Their duration of symptoms and severity of disease were the same as in the experimental group. There were no significant side-to-side differences in BMD of the calcaneus preoperatively, but 12 months postoperatively BMD of the calcaneus was 16.4% lower at the injured side compared with the noninjured side. Heavy-loaded eccentric calf-muscle training resulted in a fast recovery in all patients, equaled the side-to-side differences in muscle strength, and was not associated with side-to-side differences in BMD of the calcaneus. In this group of middle-aged recreational athletes, BMD of the calcaneus was not related to calf-muscle strength.

EQUIVALENCE OF THE β-FUNCTION OF THE VARIATIONAL APPROACH TO THAT OF QCD

The variational ansatz for the ground state wavefunctional of QCD is found to capture the antiscreening behaviour that contributes the dominant "-4" to the β-function and leads to asymptotic freedom. By considering an SU (N) purely gauge theory in the Hamiltonian formalism and choosing the Coulomb gauge, the origins of all screening and antiscreening contributions in gluon processes are found in terms of the physical degrees of freedom. The overwhelming antiscreening contribution of "-4" is seen to originate in the renormalisation of a Coulomb interaction by a transverse gluon. The lesser screening contribution of " [Formula: see text]" is seen to originate in processes involving transverse gluon interactions. It is thus apparent how the variational ansatz must be developed to capture the full running of the QCD coupling constant.

Heavy-load eccentric calf muscle training for the treatment of chronic Achilles tendinosis.

We prospectively studied the effect of heavy-load eccentric calf muscle training in 15 recreational athletes (12 men and 3 women; mean age, 44.3 +/- 7.0 years) who had the diagnosis of chronic Achilles tendinosis (degenerative changes) with a long duration of symptoms despite conventional nonsurgical treatment. Calf muscle strength and the amount of pain during activity (recorded on a visual analog scale) were measured before onset of training and after 12 weeks of eccentric training. At week 0, all patients had Achilles tendon pain not allowing running activity, and there was significantly lower eccentric and concentric calf muscle strength on the injured compared with the noninjured side. After the 12-week training period, all 15 patients were back at their preinjury levels with full running activity. There was a significant decrease in pain during activity, and the calf muscle strength on the injured side had increased significantly and did not differ significantly from that of the noninjured side. A comparison group of 15 recreational athletes with the same diagnosis and a long duration of symptoms had been treated conventionally, i.e., rest, nonsteroidal antiinflammatory drugs, changes of shoes or orthoses, physical therapy, and in all cases also with ordinary training programs. In no case was the conventional treatment successful, and all patients were ultimately treated surgically. Our treatment model with heavy-load eccentric calf muscle training has a very good short-term effect on athletes in their early forties.

Nerve distribution on the capillary network of molar gingiva in golden hamster by the silver impregnation method.

The nerve distribution on the capillary network of mandibular buccal molar gingiva in golden hamsters was studied by the silver impregnation method. By employing silver impregnation on India ink injected whole mount gingival specimens directly, we could observe the distribution of nerve fibres on the capillary network three-dimensionally. In addition, by this method, troublesome graphic reconstruction sections could also be prevented. Silver impregnated nerve fibres appeared at the periosteum of the alveolar bone and formed bundles. The full running course of the bundles of nerve fibres accompanied by blood vessels, ran longitudinally along the outer surface of the alveolar bone. When entering free gingiva, the course of the nerve fibres was random. Nerve fibres branched into many smaller branches, ran in the direction of the connective tissue papillae and formed mesh-like nerve plexuses underlying the mucosa epithelium of the gingiva. Single nerve fibres emanating from these plexuses, ran toward capillary loops and were distributed not only at the base portion of the arterial limb and the venous limb but also extended to the middle portion of the former and the latter. Single nerve fibres extended to the tip of the capillary loops, however, the so-called true capillaries, were not found.In conclusion, it is suggested that these nerve fibres may be involved in the endothelial cells of capillaries. Through transmission of efferent signals, nerve fibres perhaps play an important role in regulating the blood flow of the capillary network in the mandibular buccal gingiva.

Horizontal Vibration Suppression Method Suitable for Super-High-Speed Elevators

Horizontal vibrations of elevator cars mainly occur because a car swings as roller guides installed at corners of a car frame move on a winding guide rail at high speeds. Rider comfort in high speed elevators is worsened by these vibrations. Conventional active dampers suppressing horizontal vibrations using ac servo motors make cars heavier so driving power becomes larger, and they are not easily applied to existing elevators. An active damping control method suited to super-high-speed elevators is described which can solve these problems. The method suppresses vibrations by generating only enough magnetic force needed to suppress them only when vibrations of the car frame are produced. The vibrations are detected using acceleration detectors and magnets installed on left and right sides of the car frame. A computer simulator was made to analyze phenomena of car vibrations and to verify effects of the proposed magnetic damping controller. It was found that the vibrations generated on the cabin floor were remarkably large when left and right sides at the upper and lower parts of the car frame were swung by sine waves with the same phase. The vibrations had two resonant modes. Results obtained with the computer simulator and a full scale running simulator showed that the acceleration on the cabin floor, even at the resonant frequencies, could be reduced by the magnetic damping control to around 0.1m/s2 which would provide a comfortable ride.

EXPERIMENTAL VALIDATION OF THE TWINS PREDICTION PROGRAM FOR ROLLING NOISE, PART 1: DESCRIPTION OF THE MODEL AND METHOD

The C163 Expert Committee of the European Rail Research Institute (ERRI) concerned with Railway Noise, has been developing theoretical models for the generation of wheel/rail rolling noise. These models have been brought together into a software package, called TWINS (“Track-Wheel Interaction Noise Software”). This is intended as a tool with which different designs of wheel and track can be assessed in terms of their noise generation. This paper begins by describing briefly the various theoretical models incorporated, the assumptions made within these models and their limitations. On the basis of the input and output parameters, a methodology is derived for the validation of the model by using full scale running tests. Two sets of experiments have been performed for a range of conditions in which the input parameters (the surface roughnesses of wheel and rail) were measured as fully as possible. As well as the sound pressure during train pass-by, a number of intermediate parameters were also monitored to allow validation of parts of the model.

Model checking and boolean graphs

We describe a method for translating a satisfaction problem of the modal μ-calculus into a problem of finding a certain marking of a boolean graph. By giving algorithms to solve the graph problem, we present a global model checking algorithm for a subset of the modal μ-calculus, which has time-complexity O(| A|| T|), where | A| is the size of the assertion and | T| is the size of the model (a labelled transition system). This algorithm is extended to an algorithm for the full modal μ-calculus running in time O(| A| ad | S| ad−1 | T|), where ad is the alternation depth and | S| is the number of states in the transition system, improving on earlier presented algorithms. Moreover, a local algorithm is presented for alternation depth one. This algorithm runs in time O(| A|| T|log(| A|| T|)) and is also an improvement over earlier algorithms.

Testing of the lubrication-free GPA-Ts-16/76 blower

The existing gas pumping aggregates have oil bearings and seals, the operation of which requires a cumbersome and costly lubrication system. The significant number of breakdowns of the oil supply systems, the use of an expensive oil, the expenses for its transport, and irrevocable losses stimulated the creation of a new construction of a centrifugal compressor with the use of dry gas seals and magnetic bearings. The absence of a mechanical contact between the rotating rotor and the supports offers some advantages when using magnetic bearings: the absence of wear, the improvement of the vibration characteristics of the machines, the possibility of operating in different media, the control of the rigidity and shock-absorbing characteristics, the small power required (3-5 kW), the provision of high operating velocities, and a wide range of operating temperatures. Besides this, the system for the control of magnetic bearings permits continuous control of the rotor position, so that it canbe corrected during operation, as well as control of the vibration level and of the axial force, involving preliminary calibration of the position sensors. The need for additional equipment becomes superfluous. In 1991-1992 the M. V. Frunze Scientific and Production Association (SPA) together with the Scientific-Research Institute of Compressor Machines and VNIIEM (Moscow) developed, manufactured, and tested at the Togliatti compressor station (CS) a lubricant-free blower, built into the GPA-Ts-16/76 gas pumping aggregate. * The full running time of the lubricant-free blower was 3500 h. Based on the test results it was recommended for trial production and modernization of the existing blower park. At present work is carried out at the Syzran' CS on the modernization of four lubricant-free blowers. The construction of the support and thrust part of the rotor with magnetic bearings is presented in Fig. 1. The principle of action of "dry" seals and bearings is presented in [t]. The following tests were carried out during construction of the blower: independent tests of the magnetic-bearing control systems (MBCS), of the blower (on the air-testing stand of the M. V. Frunze SPA), of the exp!osion-proofing system of the magnetic bearings, testing of gas static seals on test stands, comparative testing of lubricant-free couplings (of the membraDe and lamellar type) on the test stands of the Association as part of the standard model of the aggregate, and testing of the auxiliary roller bearings as part of the lubricant-free blower. Independent tests of the MBCS-5 control system were carried out at the VNIIEM with the aim of determining the efficiency of the system, the conformity of the static characteristics of the regxllation channels with the design values during operation from simulators of the position sensors at an equivalent load, as well as the overloading capacity of the regulation channels at nominal and maximum loads on the bearing and at the maximum air clearance. Besides this, the per%rmance of MBCS-5 was checked at +50~ and the possibility of storage at temperatures from 5 5 to +50~ the vibration stability with an acceleration of 90 riB, and the transport suitability. The performance of MBCS-5 at +50~ was tested in a KTV/8(,G~0/2 climate and pressure chamber. The storage stability at a measurement temperature from 5 5 to 50~ was tested in the climate chamber of the T-1000. The vibration stability was checked at a frequency of 20, 50, 70, and 90 Hz with an acceleration of 90 dB at a VI~DS-1500 vibration testing stand in two positions (for 1 h at each frequency). Subjected to the tests were parts of the magnetic suspension, installed directly on the compressor (radial and axial supports, transformer). When selecting the best-suited construction for the transmission of the torque from the free turbine of the driving motor to the blower rotor the parts tested were: the standard coupling, lubricant-free membrane and lamellar couplings as parts of a standard aggregate on the full-scale testing stand of the M. V. Frunze SPA. The following parameters were recorded: the