The cosmic-ray experiment KASCADE Antoni, T; Apel, W.D; Badea, F ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2003, Letnik:
513, Številka:
3
Journal Article
Recenzirano
KASCADE has been designed to measure air showers of primary cosmic-ray energies in the PeV region and to investigate the
knee phenomenon in the all-particle energy spectrum. Several observations are ...measured simultaneously for each event by different detector systems. The experiment started to take data in 1996 and has been completed and extended since then. The individual detector systems and their performances are described. Also, the experience in long-term operation of the experiment and the interplay between different components is outlined.
A composition analysis of KASCADE air shower data is performed by means of unfolding the two-dimensional frequency spectrum of electron and muon numbers. Aim of the analysis is the determination of ...energy spectra for elemental groups representing the chemical composition of primary cosmic rays. Since such an analysis depends crucially on simulations of air showers the two different hadronic interaction models QGSJet and SIBYLL are used for their generation. The resulting primary energy spectra show that the knee in the all particle spectrum is due to a steepening of the spectra of light elements but, also, that neither of the two simulation sets is able to describe the measured data consistently over the whole energy range with discrepancies appearing in different energy regions.
•Recruitment thresholds were lowest for soleus motor units (MUs) followed by medial (MG) and then lateral gastrocnemii (LG).•Initial MU discharge rates at recruitment were greatest for LG, with no ...difference between MG and soleus.•All muscles of the triceps surae exhibited a wide range of MU recruitment thresholds up to high intensities.•In all three muscles, discharge rates displayed a positive relationship with recruitment thresholds.•The recruitment and rate coding strategies result in efficacious behavior of this synergistic group.
The triceps surae is comprised of the soleus, and medial (MG) and lateral (LG) gastrocnemii. Modulation of triceps surae motor units (MUs) is context- and muscle-dependent, yet it is unknown how the disparate components of the triceps surae work together to achieve the common goal of high-intensity voluntary isometric plantar flexion torque gradation. Thus, the purpose was to assess the interrelationships between MU recruitment thresholds (MURTs) and MU discharge rates (MUDRs) among these three muscles during contractions from low to high intensities. We sampled 157 MU action potential trains from the MG (68), LG (38) and soleus (51) using fine-wire intramuscular electromyography (EMG) during voluntary ramp isometric contractions up to 100% maximal voluntary contraction (MVC). The soleus exhibited 41% and 54% lower MURTs compared to the MG (p < 0.0001) and LG (p < 0.0001), respectively, whereas MG MURTs were 22% lower than the LG (p < 0.0001). Initial MUDRs were 35% and 26% greater for the LG compared with the MG (p < 0.0001) and soleus (p < 0.0001), but no difference was detected between the MG and soleus (p = 0.28). Finally, initial MUDRs displayed a positive relationship with MURTs for each independent triceps surae component (p ≤ 0.002). The relative differences in MU properties of each muscle in this synergistic group illustrate that MU control strategies are likely optimized with respect to the relative contribution of each muscle to plantar flexion torque or functional roles.
Cryptorchidectomy in equids: 604 cases (1977–2010) Hartman, Richard; Hawkins, Jan F; Adams, Stephen B ...
Journal of the American Veterinary Medical Association,
04/2015, Letnik:
246, Številka:
7
Journal Article
Recenzirano
Objective-To evaluate the management of equids undergoing cryptorchidectomy at a referral hospital. Design-Retrospective case series. Animals-604 client-owned equids. Procedures-Medical records of ...all equids undergoing surgical treatment of cryptorchidism from 1977 to 2010 were retrospectively reviewed. Analyses of breed, location of retained testes, accuracy of palpation per rectum for determining the location of retained testes, surgical technique, and postoperative complications were performed. Results-The most frequently affected breed was the Quarter Horse (282/604 47%), which was significantly overrepresented. Of the 604 equids, 90 (15%) had undergone previous surgical attempts at castration. Preoperative palpation per rectum was performed in 395/604 (65.4%) patients, and was accurate in predicting the location of the retained testes in 354/395 (89.6%). Surgeons were significantly more likely to be incorrect in determining the location of the retained testis by means of palpation per rectum in patients that had undergone a prior attempt at castration. For equids with abdominal cryptorchidism (360/604 59.6%), the most common surgical technique was noninvasive ptorchidectomy (298/360 82.8%). In unilateral cryptorchids (521/604 86.3%), the 2 most common sites were left abdominal (184/521 35.3%) and right inguinal (148/521 28.4%). For bilateral retention (80/604 13.2%), abdominal cryptorchidism was most common (48/80 60%). Fever was present in 138/324 (43%) equids on the first day after surgery. Postoperative fever was not significantly associated with any variables evaluated. Including postoperative (≤ 24 hours) fever, 150 of 604 (25%) patients developed postoperative complications. Excluding postoperative fever, 18 of 604 (3%) patients developed major postoperative complications; complications in 10 of 604 patients were deemed surgically related, and 3 of 604 patients died. Conclusions and Clinical Relevance-Results indicated that cryptorchidectomy in equids performed with a variety of surgical approaches was associated with minimal postoperative complications. A history of previous attempts at castration decreased the ability to accurately predict the location of the retained testis.
We present the results of an analysis of the large-scale anisotropy of cosmic rays in the PeV range. The Rayleigh formalism is applied to the right ascension distribution of extensive air showers ...measured by the KASCADE (Karlsruhe Shower Core and Array Detector) experiment. The data set contains about 10 super(8) extensive air showers in the energy range 0.7-6 PeV. No hints of anisotropy are visible in the right ascension distributions in this energy range. This accounts for all showers, as well as for subsets containing showers induced by predominantly light or heavy primary particles, respectively. Upper flux limits for Rayleigh amplitudes are determined to be between 10 super(-3) at a primary energy of 0.7 PeV and 10 super(-2) at 6 PeV.
Measurements of electron, muon and hadron lateral distributions of extensive air showers as recorded in the Karlsruhe shower core and array detector experiment are presented. The data cover the ...energy range from 5×10
14 eV up to almost 10
17 eV and extend from the inner core region to distances of 200 m. The electron and muon distributions are corrected for mutual contaminations by taking into account the detector properties in the experiment. All distributions are well described by NKG functions. The scale radii describing the electron and hadron data best are ≃30 and ≃10 m, respectively. We discuss the correlation between the scale radii and the `age' parameter as well as their dependence on shower size, zenith angle, and particle energy threshold.
The flux of cosmic-ray-induced single hadrons near sea level has been measured with the large hadron calorimeter of the KASCADE experiment. The measurement corroborates former results obtained with ...detectors of smaller size if the enlarged veto of the 304 m super(2) calorimeter surface is accounted for. The program CORSIKA/QGSJET is used to compute the cosmic-ray flux above the atmosphere. Between E sub(0) = 300 GeV and 1 PeV the primary proton spectrum can be described with a power law parameterized as dJ/dE sub(0) = (0.15 plus or minus 0.03)Eimage m super(-2) s super(-1) sr super(-1) TeV super(-1). At the lower energy end the proton flux compares well with the results from recent direct measurements.
Frequency distributions of local muon densities in high-energy extensive air showers (EAS) are presented as signature of the primary cosmic ray energy spectrum in the knee region. Together with the ...gross shower variables like shower core position, angle of incidence, and the shower sizes, the KASCADE experiment is able to measure local muon densities for two different muon energy thresholds. The spectra have been reconstructed for various core distances, as well as for particular subsamples, classified on the basis of the shower size ratio
N
μ/
N
e. The measured density spectra of the total sample exhibit clear kinks reflecting the knee of the primary energy spectrum. While relatively sharp changes of the slopes are observed in the spectrum of EAS with small values of the shower size ratio, no such feature is detected at EAS of large
N
μ/
N
e ratio in the energy range of 1–10 PeV. Comparing the spectra for various thresholds and core distances with detailed Monte Carlo simulations the validity of EAS simulations is discussed.
A survey of the northern hemisphere for astrophysical point sources with continuous emission of high-energy cosmic rays is presented. Around 4.7 x 10 super(7) extensive air showers with primary ...energies above ~300 TeV measured by the KASCADE detector field are selected for this analysis. Besides the sky survey, a search for signal excess in the regions of the Galactic plane and of selected point-source candidates has been performed. There is no evidence for any significant excess. This is valid for an analysis of all recorded showers, as well as for a data set enhanced by gamma-ray-induced showers. An upper flux limit of around 3 x 10 super(-10) m super(-2) s super(-1) for a steady point source that transits the zenith is obtained. Additionally, the distribution of the arrival directions of extensive air showers with energies above 80 PeV was studied by an autocorrelation analysis.
ObjectiveTo describe the frequency of myocardial infarction (MI) prior to the diagnosis of systemic lupus erythematosus (SLE) and within the first 2 years of follow-up.MethodsThe systemic lupus ...international collaborating clinics (SLICC) atherosclerosis inception cohort enters patients within 15 months of SLE diagnosis. MIs were reported and attributed on a specialised vascular event form. MIs were confirmed by one or more of the following: abnormal ECG, typical or atypical symptoms with ECG abnormalities and elevated enzymes (≥2 times upper limit of normal), or abnormal stress test, echocardiogram, nuclear scan or angiogram. Descriptive statistics were used.Results31 of 1848 patients who entered the cohort had an MI. Of those, 23 patients had an MI prior to SLE diagnosis or within the first 2 years of disease. Of the 23 patients studied, 60.9% were female, 78.3% were Caucasian, 8.7% black, 8.7% Hispanic and 4.3% other. The mean age at SLE diagnosis was 52.5±15.0 years. Of the 23 MIs that occurred, 16 MIs occurred at a mean of 6.1±7.0 years prior to diagnosis and 7 occurred within the first 2 years of follow-up. Risk factors associated with early MI in univariate analysis are male sex, Caucasian, older age at diagnosis, hypertension, hypercholesterolaemia, family history of MI and smoking. In multivariate analysis only age (OR=1.06 95% CI 1.03 to 1.09), hypertension (OR=5.01, 95% CI 1.38 to 18.23), hypercholesterolaemia (OR=4.43, 95% CI 1.51 to 12.99) and smoking (OR=7.50, 95% CI 2.38 to 23.57) remained significant risk factors.ConclusionsIn some patients with lupus, MI may develop even before the diagnosis of SLE or shortly thereafter, suggesting that there may be a link between autoimmune inflammation and atherosclerosis.
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