131 research outputs found
Abundance and diversity of predominant sulfate-reducing bacteria in the gut of pufferfish
Sulfate-reducing bacteria (SRB) exist in anaerobic environments, such as marine sediments, and produce hydrogen sulfide, which is toxic to marine animals. However, little is known about the ecology of SRB in the gut of fish. In the present study, we used molecular techniques to analyze the predominant SRB community in the gut of pufferfish inhabiting coastal areas of Japan. The density of the dissimilatory sulfite reductase alpha gene, dsrA, derived from SRB and total count of bacteria in guts of pufferfish was 4.4×106 - 1.8×107 copies/g and 3.5×108 - 6.3×109 cells/g, respectively, in all specimens. Clones of dsrA associated with Desulfobulbus oligotrophicus, a dominant SRB species, were detected in all 12 libraries, accounting for 57.7-94.3% of clones in each library. These results strongly suggest that SRB are indigenous bacteria in the gut of pufferfish and that hydrogen sulfide produced by SRB may be a risk factor for fish health
A New Navigation System for Minimally Invasive Total Knee Arthroplasty
A computer-assisted navigation system to be used for total knee arthroplasties (TKAs) was reported to improve the accuracy of bone resection and result in precise implant placement, but the concomitant surgical invasion and time consumption are clinical problems. We developed a computed tomography (CT)-based navigation system (NNS) to be used for minimally invasive TKA. It requires only the reference
points from a small limited area of the medial femoral condyle and proximal tibia through a skin incision to obtain optical images. Here we evaluated the usefulness and accuracy of the NNS in comparison with the commercially available BrainLAB image-free navigation system (BLS). In a clinical experiment, the registration times obtained with the NNS tended to be shorter than those obtained with the BLS, but not significantly so. The NNS group tended to be in the extended position in the sagittal plane of the distal femur within 3 degrees, and the BLS group showed rather flexed deviation in the sagittal plane of the anterior femur
Unveiling the orbital-selective electronic band reconstruction through the structural phase transition in TaTe
Tantalum ditelluride TaTe belongs to the family of layered transition
metal dichalcogenides but exhibits a unique structural phase transition at
around 170 K that accompanies the rearrangement of the Ta atomic network from a
"ribbon chain" to a "butterfly-like" pattern. While multiple mechanisms
including Fermi surface nesting and chemical bonding instabilities have been
intensively discussed, the origin of this transition remains elusive. Here we
investigate the electronic structure of single-crystalline TaTe with a
particular focus on its modifications through the phase transition, by
employing core-level and angle-resolved photoemission spectroscopy combined
with first-principles calculations. Temperature-dependent core-level
spectroscopy demonstrates a splitting of the Ta core-level spectra through
the phase transition indicative of the Ta-dominated electronic state
reconstruction. Low-energy electronic state measurements further reveal an
unusual kink-like band reconstruction occurring at the Brillouin zone boundary,
which cannot be explained by Fermi surface nesting or band folding effects. On
the basis of the orbital-projected band calculations, this band reconstruction
is mainly attributed to the modifications of specific Ta states, namely
the orbitals (the ones elongating along the ribbon chains) at the
center Ta sites of the ribbon chains. The present results highlight the strong
orbital-dependent electronic state reconstruction through the phase transition
in this system and provide fundamental insights towards understanding complex
electron-lattice-bond coupled phenomena.Comment: 21 pages, 5 figure
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