1,545 research outputs found
Optical trapping and surgery of living yeast cells using a single laser
We present optical trapping and surgery of living yeast cells using two operational modes of a single laser. We used a focused laser beam operating in continuous-wave mode for noninvasive optical trapping and manipulation of single yeast cell. We verified that such operational mode of the laser does not cause any destructive effect on yeast cell wall. By changing the operation of the laser to femtosecond-pulsed mode, we show that a tightly focused beam dissects the yeast cell walls via nonlinear absorption. Lastly, using the combined technique of optical microsurgery and trapping, we demonstrate intracellular organelle extraction and manipulation from a yeast cell. The technique established here will be useful as an efficient method for both surgery and manipulation of living cells using a single laser beam.The project has been funded by the Philippine Council
for Advanced Science and Technology Research and Development
PCASTRD. J. Ando acknowledges the support of
the Japan Student Services Organization JASSO for the
short-term student exchange promotion program
Exchange Effects and SU4 Invariance in Electromagnetic and Weak Transitions
Here V and A denote the vector and axial vector hadronic currents, with the upper index referring to isospin and the lower one to Lorentz space (k=l, 2 and 3). Particular emphasis is given to the treatment of muon capture. The equality between the vector and axial vector matrix elements and the connection of the vector matrix elements to the photoabsorption cross section are discussed for this process. Finally we draw some conclusions about many-body effects in electromagnetic and weak nuclear transitions from the current algebra and SU4 invariance for the nuclear Hamiltonian
低加速電子線 SEM / STEM を用いた局在場可視化技術
High-sensitive visualization of the local electric and magnetic field is possible using a low energy electron beam combining with a simple grid detector configuration. The beam deflection goes along with the clear principle that the larger deflection can be induced by lower energy electron based on the Rutherford scattering scheme. The field distribution around two-dimensional materials allows quantitative analysis of the local field, showing good agreements with FEM simulation. Well defined beam scanning control established in the recent scanning electron microscope (SEM) can project the detector grid image superimposed on the specimen image. And thus the localized field distribution was easily visualized through a simple E-filed vector translation based on the deflection configuration. Detailed techniques and the analysis were described from the viewpoint of practical applications
Consistent map building in petrochemical complexes for firefighter robots using SLAM based on GPS and LIDAR
The objective of this study was to achieve simultaneous localization and mapping (SLAM) of firefighter robots for petrochemical complexes. Consistency of the SLAM map is important because human operators compare the map with aerial images and identify target positions on the map. The global positioning system (GPS) enables increased consistency. Therefore, this paper describes two Rao-Blackwellized particle filters (RBPFs) based on GPS and light detection and ranging (LIDAR) as SLAM solutions. Fast-SLAM 1.0 and Fast-SLAM 2.0 were used in grid maps for RBPFs in this study. We herein propose the use of Fast-SLAM to combine GPS and LIDAR. The difference between the original Fast-SLAM and the proposed method is the use of the log-likelihood function of GPS; the proposed combination method is implemented using a probabilistic mathematics formulation. The proposed methods were evaluated using sensor data measured in a real petrochemical complex in Japan ranging in size from 550–380 m. RTK-GPS data was used for the GPS measurement and had an availability of 56%. Our results showed that Fast-SLAM 2.0 based on GPS and LIDAR in a dense grid map produced the best results. There was significant improvement in alignment to aerial data, and the mean square root error was 0.65 m. To evaluate the mapping consistency, accurate 3D point cloud data measured by Faro Focus 3D (± 3 mm) was used as the ground truth. Building sizes were compared; the minimum mean errors were 0.17 and 0.08 m for the oil refinery and management building area and the area of a sparse building layout with large oil tanks, respectively. Consequently, a consistent map, which was also consistent with an aerial map (from Google Maps), was built by Fast-SLAM 1.0 and 2.0 based on GPS and LIDAR. Our method reproduced map consistency results for ten runs with a variance of ± 0.3 m. Our method reproduced map consistency results with a global accuracy of 0.52 m in a low RTK-Fix-GPS environment, which was a factory with a building layout similar to petrochemical complexes with 20.9% of RTK-Fix-GPS data availability
Involvement of TRPV3 and TRPM8 ion channel proteins in induction of mammalian cold-inducible proteins
Cold-inducible RNA-binding protein (CIRP), RNA-binding motif protein 3 (RBM3) and serine and arginine rich splicing factor 5 (SRSF5) are RNA-binding proteins that are transcriptionally upregulated in response to moderately low temperatures and a variety of cellular stresses in mammalian cells. Induction of these cold-inducible proteins (CIPs) is dependent on transient receptor potential (TRP) V4 channel protein, but seems independent of its ion channel activity. We herein report that in addition to TRPV4, TRPV3 and TRPM8 are necessary for the induction of CIPs. We established cell lines from the lung of TRPV4-knockout (KO) mouse, and observed induction of CIPs in them by western blot analysis. A TRPV4 antagonist RN1734 suppressed the induction in wild-type mouse cells, but not in TRPV4-KO cells. A TRPV3 channel blocker S408271 and a TRPM8 channel blocker AMTB as well as siRNAs against TRPV3 and TRPM8 suppressed the CIP induction in mouse TRPV4-KO cells and human U-2 OS cells. A TRPV3 channel agonist 2-APB induced CIP expression, but camphor did not. Neither did a TRPM8 channel agonist WS-12. These results suggest that TRPV4, TRPV3 and TRPM8 proteins, but not their ion channel activities are necessary for the induction of CIPs at 32 °C. Identification of proteins that differentially interact with these TRP channels at 37 °C and 32 °C would help elucidate the underlying mechanisms of CIP induction by hypothermia
Ecosystem and Fishery of Manila Clam (Ruditapes philippinarum) in Ise-Bay Related to Eco-Compatible Management of Its River Basin Complex
AbstractIse bay, Japan, is located at the river mouth of 10 class-A rivers, and its environment is closely related to management of their river basin complex (RBC). We developed a model to describe the ecosystem of RBC by developing three tool boxes: TB1 to describe the water/material flux network, TB2 to describe ecosystem mechanism in various categories of landscapes, and TB3 to standardize ecosystem services received at local sites and integrate them throughout RBC. Ecosystem has a function to change the fluxes, which is evaluated by TB2, and such flux change can be fed back to the flux networks in TB1. The outputs of the fluxes from the RBC are inputs for currents of water with various qualities to the bay, which can be computed by bay-dynamics modeling. Then it provides various fluxes from the bay interior to landscapes located along coastal zone, and it supports ecosystem there. Fishery is a kind of ecosystem service there. We focused on bivalve, Manila clam (Ruditapes philippinarum) because it uses various landscapes in a bay through its life cycle and it provides fishery activity as ecosystem service. We have developed TB1 and TB2 also in bay area successfully. Then, we evaluate the transition of quality of environments of RBC including Ise bay from the past to the present by using TB1-TB3 for river basin and bay area. Furthermore, we forecast the future situation and then we discuss how we can improve it through various combinations of measures and policies in the RBC as well as in the bay
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