Abstract
The shape of the bedrock underneath alpine glaciers bears vital information on the erosional mechanism related to the flow of ice. So far, several geophysical exploration methods have been ...proposed to map the bedrock topography though with limited accuracy. Here we illustrate the first results from a technology, called cosmic ray muon radiography, newly applied in glacial geology to investigate the bedrock geometry beneath the Aletsch Glacier situated in the Central Swiss Alps. For this purpose we installed new cosmic muon detectors made of emulsion films at three sites along the Jungfrau railway tunnel and measured the shape of the bedrock under the uppermost part of Aletsch Glacier (Jungfraufirn). Our results constrain the continuation of the bedrock‐ice interface up to a depth of 50 m below the surface, where the bedrock underneath the glacier strikes NE‐SW and dips at 45° ± 5°. This documents the first successful application of this technology to a glaciated environment.
Key Points
Muon radiography is applied to an alpine glacier for the first time
The technique reveals the depth profile of the bedrock under the uppermost part of the Aletsch Glacier
The bedrock shape gives clues on the mechanism of the glacial erosion
Mountain glaciers form landscapes with U-shaped valleys, roche moutonées and overdeepenings through bedrock erosion. However, little evidence for active glacial carving has been provided particularly ...for areas above the Equilibrium Line Altitude (ELA) where glaciers originate. This is mainly due to our lack of information about the shape of the bedrock underneath active glaciers in highly elevated areas. In the past years, the bedrock morphology underneath active glaciers has been studied by geophysical methods in order to infer the subglacial mechanisms of bedrock erosion. However, these comprise surveys on the glaciers' surface, from where it has been difficult to investigate the lateral boundary between the ice and the bedrock with sufficient resolution. Here we perform a muon-radiographic inspection of the Eiger glacier (Switzerland, European Alps) with the aid of cosmic-ray muon attenuation. We find a reach (600 × 300 m) within the accumulation area where strong lateral glacial erosion has cut nearly vertically into the underlying bedrock. This suggests that the Eiger glacier has profoundly sculpted its bedrock in its accumulation area. This also reveals that the cosmic-ray muon radiography is an ideal technology to reconstruct the shape of the bedrock underneath an active glacier.
Learning achievement is one indicator in determining the success of an educational institution, student learning achievement consists of three aspects, namely cognitive, affective and psychomotor ...aspects. The student has unique and distinctive characteristics in behaving as well as in the learning process. A good learning process will result in a good learning achievement as well. Learning achievement is a proof of the success of learning or ability of a person in doing learning activities in accordance with the weight achieved. Many factors that affect learning achievement one of them is the student's personality. Personality can affect student achievement level. This study uses a descriptive correlative design that aims to determine the relationship between the personality with student achievement. The sample in this study amounted to 234 students of the Faculty of Nursing USU, with the approach of proportionate stratified random sampling. Chi-square test results obtained a relationship of personality with student achievement with p-value value of 0.043. Furthermore, the test statistic nonparametric test sperman rho that produces strength correlation relationship of the personality variable to the achievement index of -0.050. The suggestion for further research is to include other variables that influence academic achievement such as interest, motivation, lecturer and teaching method and environmental factors so that can be seen the influence of these variables.
Interference of matter waves is at the heart of quantum physics and has been observed for a wide range of particles from electrons to complex molecules. Here, we demonstrate matter wave interference ...of single positrons using a period-magnifying Talbot-Lau interferometer based on material diffraction gratings. The system produced high-contrast periodic fringes, which were detected by means of nuclear emulsions capable of determining the impact point of each individual positron with submicrometric resolution. The measured energy dependence of fringe contrast in the range of 8 to 16 keV proves the quantum-mechanical origin of the periodic pattern and excludes classical projective effects, providing the first observation to date of antimatter wave interference. Future applications of this interferometric technique include the measurement of the gravitational acceleration of neutral antimatter systems exploiting the inertial sensing capabilities of Talbot-Lau interference.
Industrial mass production of nuclear emulsion film has been realized by the introduction of new photographic technologies.
In addition, emulsion-refreshing capability (erasing unwanted tracks before ...its use) was implemented by controlling the fading characteristics of the gel. The gel properties were optimized in order to satisfy this requirement; rapid track erasing at the erasing condition and minimum fading during the running of experiments.
Emulsion films with this capability are crucial for large-scale applications like the long base-line neutrino experiment, OPERA, which intend to detect Tau neutrino appearance at 732
km from the beam source.
Mucormycosis is a life-threatening infectious disease that occurs most commonly in immunocompromised patients such as those with hematological malignancies. Its clinical symptoms and associated ...radiological findings vary and specific biomarkers and culture characteristics have not been defined. An 85-year-old man who had been treated for myelodysplastic syndrome and tuberculosis for several months presented with subacute fever and worsening left-side chest pain. Contrast-enhanced computed tomography images depicted massive tumor-like consolidation without enhancement, expanding from the left lower lobe. Emboli that did not respond to anticoagulants were detected in the left descending pulmonary artery. Despite intensive treatment he developed multiple organ failure and died 47 days after hospitalization. Gross pathology of a lung autopsy specimen revealed left lower pulmonary arterial emboli and pulmonary infarction, which was concluded to be the direct cause of death. The emboli were histopathologically identified as invasive mycelia in vessels. Mucor sp. was detected via real-time polymerase chain reaction and immunohistopathological analyses revealed that the mold in the blood vessels of lung tissue was partially positive for the mucor antigen. In the present case of Mucor sp. pulmonary emboli in a patient with myelodysplastic syndrome, radiographic findings were hard to distinguish from those typical of a lung abscess.
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