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A fast-sampling fast-ion D-alpha (F-FIDA) measurement has been developed in the large helical device in order to investigate fast ion dynamics associated with helically trapped fast-ion-driven Magnetohydrodynamic (MHD) bursts. F-FIDA consists of a multi-anode photomultiplier tube (PMT) and achieves a sampling rate of 10 kHz. During the deuterium experiment campaign in 2022, F-FIDA measured the spectrum of perpendicular fast ions, using perpendicular lines of sight. We compared F-FIDA with conventional FIDA, using an electron multiplying charge coupled device, and confirmed that the time-averaged images were generally consistent between the two. The statistical properties of the temporal evolution associated with MHD bursts were analyzed using a conditional sampling technique. The results showed that the PMT signal varied in different spatial and wavelength channels. Although the signal-to-noise ratio was poor and there was room for improvement, it could provide useful information for studies on the phase-space dynamics of fast ions. [ABSTRACT FROM AUTHOR]

Nonlinear fluid simulation of drift wave turbulence in the presence of symmetry breaking particle source is performed for the cylindrical magnetized plasmas. It is demonstrated that the symmetry breaking of the system directly affects the selection rule of structure formations, the streamers disappear, and the zonal flows are enhanced in the case with the symmetry breaking. The symmetry breaking is introduced in the flux-driven simulation by inducing the particle source whose amplitude depends on the azimuthal angle. The symmetry breaking mode is driven stationarily, and the nonlinear process of the drift waves is significantly modified. By scanning the amplitude of the symmetry breaking source, the structure formation processes are systematically investigated. In addition, the nonlinear forces of the turbulence show the relaxation of the density gradient and the drive of the perpendicular/parallel flows in a two-dimensional manner. [ABSTRACT FROM AUTHOR]

Fourier-rectangular function (FRF) transform [K. Yamasaki et al., J. Appl. Phys. 126, 043304 (2019)] is used to analyze the structure and dynamics of plasma with cylindrical symmetry. In this article, a new technique based on FRF transform is proposed to elucidate the polarization characteristics of azimuthal modes and fluctuations. The application results are shown for a two-dimensional tomography image of linear cylindrical plasma. The method successfully resolves the polarization characteristics of azimuthal modes and attributes the intermittent behavior of the m = 1 mode to its polarization characteristics. [ABSTRACT FROM AUTHOR]

Masushi Kohta,1 Kazumi Sakamoto,2 Yasuhiro Kawachi,3 Tsunao Oh-i4 1Medical Engineering Laboratory, ALCARE Co, Ltd, Tokyo, 2Department of Nursing, 3Department of Dermatology, Tokyo Medical University Ibaraki Medical Center, Ibaraki, 4Department of Dermatology, Tokyo Medical University Hachioji Medical Center, Tokyo, Japan Purpose: There have been previous clinical studies regarding the impact of dressings on the prevention of pressure ulcer development. However, it remains unclear whether one type of dressing is better than any other type for preventing ulcer development during surgery. Therefore, we compared the effects of ceramide 2-containing hydrocolloid dressing with film dressings in high-risk patients with regard to reducing the incidence of pressure ulcer development during surgery. Patients and methods: A prospective, randomized, open-label, clinical trial was conducted involving patients who were at a high risk of developing pressure ulcers at a Japanese hospital. The intervention group received ceramide 2-containing hydrocolloid dressings (n=66), and the control group received film dressings (n=64). The primary end point was the incidence rate of pressure ulcer development in both groups; skin damage, such as blanchable erythema, skin discoloration, contact dermatitis, and stripped skin, was recorded as the secondary end point. The relative risk (RR) and 95% confidence interval (CI) were assessed to compare the probability ratios of pressure ulcer development between the groups. Results: There were significantly fewer patients who developed pressure ulcers in the intervention group than in the control group (RR, 0.37; 95% CI, 0.05–0.99; P=0.04). In the post hoc subgroup analysis, the superiority of the intervention group was more marked when patients had a lower body mass index (P=0.02), lower albumin values (P=0.07), and operation time of 3 hours or more and less than 6 hours (P=0.03). There was no evidence of any statistically significant differences in the types of skin damage reported. Conclusion: Application of ceramide 2-containing hydrocolloid dressing reduced the risk of pressure ulcer development in patients who were at a high risk during surgery compared with film dressings. Keywords: operating room, wound dressing, friction, skin protection, shear

We present the evidence that drift waves can develop into nonlinear breathers. The theoretical analysis predicts that drift waves with secondary flow can excite the nonlinear breather through modulational instability. It is found that the simultaneous modulation of both amplitude and phase is a relevant feature of breather excitation. These features are used to elucidate the excitation of drift breather in a linear plasma experiment. The drift breathers are found to be excited frequently and intermittently. The transient increase in the transport flux is also demonstrated. We argue that there exists a critical condition on the wave amplitude for breather excitation. [ABSTRACT FROM AUTHOR]

This paper presents the experimental identification of the dynamic interaction between three fluctuations excited by different thermodynamical forces in a linear plasma. The observed fluctuations are characterized as an axial symmetric mode, a drift wave, and an azimuthally symmetric potential fluctuation from the spatiotemporal structures measured with Langmuir probe arrays. The intermittent burst of the axial symmetric mode is observed by the instantaneous wave number spectrum. The energy transfer analysis revealed that the axially symmetric mode gains energy from the other mode during the burst while the drift wave loses energy. The intermittent burst synchronizes with the azimuthal symmetric potential fluctuation. [ABSTRACT FROM AUTHOR]

Interaction between drift wave turbulence and streamer flow in magnetized plasmas is investigated in the framework of wave-kinetic theory. By performing a wave-kinetic simulation of turbulence coupling with the streamer flow, the role of the phase-space dynamics of turbulence is clarified. Here, the phase-space consists of the real space and wavenumber space. As a consequence of the phase-space dynamics, the turbulence is trapped in the flow and propagates with the streamer. Because of the trapping, the asymmetry of the turbulence intensity with respect to the sign of the flow curvature appears. The trajectories of the turbulence wave-packet, which are the characteristic curves of the wave-kinetic solution, can be categorized by the trapping, passing, and scattering. Therefore, the obtained phase-space structure of the turbulence can be understood by their trajectories. The propagation direction and speed are found to be governed by the turbulence spectrum. The obtained characteristics can be explained by the theoretical analysis. [ABSTRACT FROM AUTHOR]

This article discusses triad transfer analysis via quadratic nonlinearity. To avoid fictitious interactions, symmetrization of the triad transfer is reviewed, including arbitrary orthogonal decomposition and coarse graining. The directional representation of the symmetrized triad transfer is proposed by minimizing the number of edges in a network graph of triad interactions with keeping the energy consistency. The directional representation simplifies visualization and allows us to reduce the energy transfer into a one-to-one relation, while eliminating fictitious interactions in non-symmetrized triad transfer functions. Energy transfer processes among plasma turbulent fluctuations that decompose by the singular value decomposition are analyzed as an application. A network graph visualization clearly demonstrates the importance of symmetrization and the consistency between the symmetrized triad transfer and its directional representation. [ABSTRACT FROM AUTHOR]

The conditional average is a technique to extract a typical waveform from bursty or quasi-periodic phenomena regarded as a combination of deterministic trend and residual fluctuations (or probabilistic part). The article proposes a new conditional average technique that is an extension from what is called the template method that allows automatic selection, using the correlation analysis, of the identical events of the phenomena. The proposed method is applied on a quasi-periodic oscillation observed in a linear magnetized plasma, and successfully divides the phenomenon into the deterministic trend and residual fluctuations. Moreover, the statistical error analysis on the power of the residual fluctuations discloses the presence of mutual interactions between the deterministic trend and the residual fluctuations. [ABSTRACT FROM AUTHOR]

A method to quantify the energy transfer among turbulent structures using singular value decomposition (SVD) is presented. We apply the method to numerical turbulence data obtained from a global plasma simulation using the Hasegawa–Wakatani fluid model, in which the Kelvin–Helmholtz instability plays a dominant role. Using the SVD method, the electrostatic potential is decomposed into a background potential deformation, a zonal flow, a coherent mode and an intermittent structure. Thus there are four key structures, as distinct from the three found in conventional theory. The kinetic energy of each structure is evaluated, and the limit cycle among them is obtained. In the limit cycle, an abrupt change of the background is found to be synchronised with the period of the zonal flow. The energy transfer function of each turbulence structure, which is defined on the basis of a vorticity equation, is evaluated. This then provides physical understanding of how the limit cycle is sustained by dynamical changes in the energy transfer among structures over the its period. In addition, it is shown that the abrupt deformation of the background is caused by the non-linear self-coupling of the intermittent structure. [ABSTRACT FROM AUTHOR]

In order to explore the impact of the neutrals on the plasma turbulence, a new gas puff system is developed for a linear magnetized plasma column PANTA. Helium gas is injected into the argon plasma without changing the electron density profile. After the helium gas puff, the dominant fluctuation mode changes from the broadband m = 2 drift wave to the coherent m = 1 mode, where m is the azimuthal mode number. Accordingly, the property of the nonlinear coupling with other fluctuating modes changes from broadband couplings to coherent couplings. [ABSTRACT FROM AUTHOR]

The streamer-driven particle flux is evaluated experimentally in a linear cylindrical plasma. The streamers, a radially elongated and azimuthally localized structure created in turbulent plasma, really induce ballistic transport, and directly connect the plasma core to the edge within one order faster time scale than that of turbulence. The occurrence of large transport deviates from a Gaussian distribution and is likely to obey a power law. The fundamental plasma experiment clearly shows the significant and essential contributions of streamers to cross-field transport and structural formation of turbulent plasmas. [ABSTRACT FROM AUTHOR]

Early Palaeozoic basement rocks in South Westland consist of regionally metamorphosed Greenland Group of probable Ordovician depositional age. Correlative and formerly contiguous Gondwana margin rocks are also found in Antarctica and eastern Australia. Major protoliths are variably foliated sandstone and mudstone, with rare scattered calcareous lenses. Field, petrographic and electron microprobe data reveal a progressive, regional, southeast-wards increase in metamorphic grade in a 2600 km2 area between Martins Bay and Fox Glacier. We define new chlorite, biotite–albite, biotite–calcic plagioclase and sillimanite–microcline zones. Minerals such as cordierite and andalusite, along with semi-schistose textures, indicate a low P/T (pressure/temperature) Buchan style of regional metamorphism spanning the lower greenschist to upper amphibolite facies. This contrasts with medium to high P/T metamorphism in the Haast Schist east of the Alpine Fault. In South Westland, peak metamorphism is loosely constrained as Devonian to Carboniferous (330–375 Ma) in age; the present-day isograd pattern was mostly established by the Late Cretaceous and has not been strongly influenced by Alpine Fault deformation. [ABSTRACT FROM AUTHOR]

Tyrosine phosphorylation is widely recognized as playing an important role in cell differentiation, proliferation and carcinogenesis. We used the polymerase chain reaction ( PCR) method to identify protein tyrosine kinases that were expressed in the skin. Mixed oligonucleotide probes were used to amplify and screen neonatal murine skin mRNA for clones encoding amino acid contiguities, the conservation of which is characteristic of the protein tyrosine kinase family. When the PCR products were sequenced, a novel clone encoding protein tyrosine kinase, PTK70, was identified. A lull-length cDNA was isolated from a mouse thymus cDNA library. The nucleotide and deduced amino acid sequence showed that it featured src-homology (SH) 2 domain. SH3 domain and kinase domain like other src Family protein tyrosine kinases, but lacked the N-terminal myristylation site and C-terminal tyrosine residue. Although the mRNA of PTK70 was detected in various tissues ubiquitously, the degree of its expression differed among tissues. Murine skin is one in which PTK70 was expressed strongly, with its expression being much stronger in the epidermis and in the cell line derived from murine keratinocytes than in those from melanoma or fibroblast cell lines. These evidences suggest that PTK70 may be involved in proliferation or differentiation of keratinocytes in the skin. [ABSTRACT FROM AUTHOR]