Ab initio study of the photoabsorption of 4^4He

There are some discrepancies in the low energy data on the photoabsorption cross section of $^4$He. We calculate the cross section with realistic nuclear forces and explicitly correlated Gaussian functions. Final state interactions and two- and three-body decay channels are taken into account. The cross section is evaluated in two methods: With the complex scaling method the total absorption cross section is obtained up to the rest energy of a pion, and with the microscopic $R$-matrix method both cross sections $^4$He($\gamma, p$)$^3$H and $^4$He($\gamma, n$)$^3$He are calculated below 40\,MeV. Both methods give virtually the same result. The cross section rises sharply from the $^3$H+$p$ threshold, reaching a giant resonance peak at 26--27\,MeV. Our calculation reproduces almost all the data above 30\,MeV. We stress the importance of $^3$H+$p$ and $^3$He+$n$ cluster configurations on the cross section as well as the effect of the one-pion exchange potential on the photonuclear sum rule.Comment: 15 pages, 12 figure

Sequential Development of Putaminal Hemorrhage and Corona Radiata Infarction in the Same Lenticulostriate Arterial Territory

Putaminal hemorrhage is a common type of spontaneous cerebral hemorrhage. However, to our knowledge, there have been no reports of sequential cerebral hemorrhage and infarction in the same perforating arterial territory. Herein, we present the first reported case of the sequential development of putaminal hemorrhage and corona radiata infarction in the same lenticulostriate arterial (LSA) territory. Early intensive blood pressure lowering treatment may have aggravated ischemic damage. If a patient presents with motor weakness that cannot be explained by putaminal hemorrhage, the sequential development of corona radiata infarction in the same LSA territory should be ruled out

Galactic Center Radio Constraints on Gamma-Ray Lines from Dark Matter Annihilation

Recent evidence for one or more gamma-ray lines at ~ 130 GeV in the Fermi-LAT data from the Galactic Center has been interpreted as a hint for dark matter annihilation to Z{\gamma} or H{\gamma} with an annihilation cross section, ~ 10^{-27} cm^3 s^{-1} . We test this hypothesis by comparing synchrotron fluxes due to the electrons and positrons from the decay of the Z or the H boson only in the Galactic Center against radio data from the same region in the Galactic Center. We find that the radio data from single dish telescopes marginally constrain this interpretation of the claimed gamma lines for a contracted NFW profile. Already-operational radio telescopes such as LWA, VLA-Low and LOFAR, and future radio telescopes like SKA, which are sensitive to annihilation cross sections as small as 10^{-28} cm^3 s^{-1}, can confirm or rule out this scenario very soon. We discuss the assumptions on the dark matter profile, magnetic fields, and background radiation density profiles, and show that the constraints are relatively robust for any reasonable assumptions. Independent of the above said recent developments, we emphasize that our radio constraints apply to all models where dark matter annihilates to Z{\gamma} or H{\gamma}.Comment: v3: 18 pages, 7 figures. Minor changes. Published in Phys. Rev.

8Li+alpha decay of 12B and its possible astrophysical implications

The 12B excitation energy spectrum has been obtained from coincidence measurements of the 9Be+7Li -> 2alpha+8Li reaction at E{0}=52 MeV. The decay of the states at excitations between 10 and 16 Mev into alpha$+8Li has been observed for the first time. Observed alpha-decay indicates possible cluster structure of the 12B excited states. The influence of these states on the cross section of the astrophysically important 8Li(alpha,n)11B and 9Be+t reactions is discussed and the results are compared with existing results.Comment: accepted for publication in Europhysics Letter

Operation-Microscope-Mounted Touch Display Tablet Computer for Intraoperative Imaging Visualization

OBJECTIVE: The authors have developed a novel sterile draped touch display solution for convenient intraoperative access to imaging data. This study describes the technology and clinical experience of the system. METHODS: We developed a flexible, mounted touch display solution (Apple iPad) that allows fixation of the display on the operation microscope and fine adjustments during surgery when the microscope is moved. We compared this setup with a conventional wall-mounted flat-panel and a mobile display stand in illustrative cases of vestibular schwannoma. RESULTS: The surgeon was able to employ the system without the need to leave the operation field or the need for external assistance while referring to imaging data. Commanding through imaging data with sterile gloves on the touch display was more convenient, more precise, and faster compared with other modalities. CONCLUSION: The operation-microscope-mounted touch display provides useful assistance for intraoperative imaging visualization in neurosurgical procedures.ArticleWORLD NEUROSURGERY. 77(2):381-383 (2012)journal articl

Finger Motion Classification by Forearm Skin Surface Vibration Signals

The development of prosthetic hand systems with both decoration and motion functionality for hand amputees has attracted wide research interests. Motion-related myoelectric potentials measured from the surface of upper part of forearms were mostly employed to construct the interface between amputees and prosthesis

Digital imaging to simultaneously study device lifetimes of multiple dye-sensitized solar cells

In situ degradation of multiple dyes (D35, N719, SQ1 and SQ2) has been investigated simultaneously using digital imaging and colour analysis. The approach has been used to study the air stability of N719 and squaraine dyes adsorbed onto TiO2 films with the data suggesting this method could be used as a rapid screening technique for DSC dyes and other solar cell components. Full DSC devices have then been tested using either D35 or N719 dyes and these data have been correlated with UV-vis, IR and XPS spectroscopy, mass spectrometry, TLC and DSC device performance. Using this method, up to 21 samples have been tested simultaneously ensuring consistent sample exposure. Liquid electrolyte DSC devices have been tested under light soaking including the first report of D35 testing with I�/I3 � electrolyte whilst operating at open circuit, short circuit, or under load, with the slowest degradation shown at open circuit. D35 lifetime data suggest that this dye degrades after ca. 370 h light soaking regardless of UV filtering. Control, N719 devices have also been light soaked for 2500 h to verify the imaging method and the N719 device data confirm that UV filtration is essential to protect the dye and I3 �/I� electrolyte redox couple to maintain device lifetime. The data show a direct link between the colour intensity and/or hue of device sub-components and device degradation, enabling “real time” diagnosis of device failure mechanisms