6,688 research outputs found
Nano-mechanical behavior of ultra-stable amorphous metallic thin films
Metallic glass has amorphous structure that behave mechanically like solids but show catastrophic failure due to shear band propagation induced by short range order structure, and they are generally produced by quenching. Recently, it is observed that the slower cooling rate provides the larger time available for atoms to rearrange structure before freezing in glassy state, leading to glass transition temperature and thermal stability. These glasses with enhanced thermal stability synthesized by controlled cooling rate make it useful in various field such as mechanical or oxidation protection material. However, mechanical behavior for metallic glass with extraordinary thermodynamic and kinetic stability has not been studied. In this research, we developed a ultrastable metallic glass thin film by physical vapor deposition process at ambient temperature. Thermal stability is investigated using acceleration testing. Mechanical properties are measured using in-situ tensile testing and discuss thermal stability and fracture behavior dependent on compositio
Crystal structure of Cmr5 from Pyrococcus furiosus and its functional implications
AbstractThe bacterial acquired immune system consists of clustered regularly interspaced short palindromic repeats (CRISPRs) and CRIPSR-associated (Cas) genes, which include Cas-module repeat-associated mysterious proteins (Cmr). The six Cmr proteins of Pyrococcus furiosus (pfCmr1–pfCmr6) form a Cmr effector complex that functions against exogenous nucleic acid. Among the Cmr proteins, the role of pfCmr5 and its involvement in the complex’s cleavage activity have been obscure. The elucidated pfCmr5 structure has two inserted α-helices compared with the other trimeric Cmr5 structure. However, pfCmr5 exists as a monomeric protein both in the crystalline state and in solution. In vitro assays indicate that pfCmr5 interacts with pfCmr4. These structural and biophysical data might help in understanding the complicated and ill-characterized Cmr effector complex.Structured summary of protein interactionspfCmr4 and pfCmr5 bind by molecular sieving (View interaction)pfCmr4 and pfCmr4 bind by molecular sieving (View interaction)pfCmr5 and pfCmr4 bind by ion exchange chromatography (View interaction
A heuristic inquiry : encountering the self with symbolic images
This heuristic journey to the Self occurred spontaneously from my life quest. While living with and gazing at symbolic images in my room, I captured their voices unfolding the same message about "going deep down inward to search for the Self." I followed the message coming from inner wisdom and realized that my symbolic images and their message were closely related to Cari Jung's perspective of the Self. In this heuristic self-inquiry, I have pursued the self-experience leading me to the essence of the Self, and the symbolic images along with reflexive knowledge were a major guideline to the self-experience of encountering the Self in a metaphoric, safe way. I experienced the symbolic manifestations of the Self by the images of the Shadow, pond, castle, mandala, apple, heart, Christ, and lotus flower. I also experienced fears, which caused resistance or hesitation in my heuristic journey to the Self. In the process of recognizing and resolving my fears, I could proceed with my heuristic self-inquiry and diminished my resistance. Then, I could expand my limited concepts of the Self, God, and my religion and reached a new understanding of the essence of the Self that the Self is a manifestation of God residing in the heart, deep inside of us. Also I discovered that a heuristic journey on a topic can have several layers of heuristic inquiry, like a spiral shape, in aiming at reaching the core of what is being investigated. I hope this heuristic self-inquiry can be beneficial to others to better understand the Self in their process of healing, maturity, or transformation, and as well to art therapists to better understand their clients within artwork processes in clinical practic
Quasi-normal modes of dyonic black holes and magneto-hydrodynamics
We revisit the magneto-hydrodynamics in (2+1) dimensions and confirm that it
is consistent with the quasi-normal modes of the (3+1) dimensional dyonic black
holes in the most general set-up with finite density, magnetic field and wave
vector. We investigate all possible modes (sound, shear, diffusion, cyclotron
etc.) and their interplay. For the magneto-hydrodynamics we perform a complete
and detailed analysis correcting some prefactors in the literature, which is
important for the comparison with quasi-normal modes. For the quasi-normal mode
computations in holography we identify the independent fluctuation variables of
the dyonic black holes, which is nontrivial at finite density and magnetic
field. As an application of the quasi-normal modes of the dyonic black holes we
investigate a transport property, the diffusion constant. We find that the
diffusion constant at finite density and magnetic field saturates the lower
bound at low temperature. We show that this bound can be understood from the
pole-skipping point.Comment: 27 pages, 6 figure
Fishbone-Associated Actinomycosis of the Anterior Cervical Space: A Diagnostic Dilemma
We report the imaging and pathologic findings of fishbone-associated actinomycosis of the anterior cervical space in a 57-year-old man, misdiagnosed preoperatively as a malignancy originating from thyroglossal duct cyst. CT revealed an enhancing mass containing a small abscess pocket and two sharp linear calcifications within it, which infiltrated into the strap muscle. Pathologic examination demonstrated two fishbones within the actinomycotic abscess. Fishbone-associated actinomycosis should be considered when a cervical mass contains sharp linear calcifications
Island in dyonic black holes: doubly holographic theory
We investigate the entanglement between the eternal black hole and Hawking
radiation. For this purpose, we utilize the doubly holographic theories and
study the entanglement entropy of the radiation to find the Page curve
consistent with the unitarity principle. Doubly holographic theories introduce
two types of boundaries in the AdS bulk, namely the usual AdS boundary and the
Planck brane. In such a setup, we calculate the entanglement entropy by
examining two extremal surfaces: the Hartman-Maldacena (HM) surface and the
island surface. The latter surface emerges when the island appears on the
Planck brane. In this paper, we provide a detailed analysis of dyonic black
holes with regard to the Page curve in the context of the doubly holographic
setup. To begin with, we ascertain that the pertinent topological terms must be
included in the Planck brane to describe the systems at finite density and
magnetic field. Furthermore, we also develop a general numerical method to
compute the time-dependent HM surface and achieve excellent agreement between
the numerical results and analytical expressions. Utilizing numerical
methodology, we find that the entanglement entropy of dyonic black holes
exhibits unitary evolution over time, wherein it grows in early time and
reaches saturation after the Page time. The initial growth can be explained by
the HM surface, while the saturation is attributed to the island surface. In
addition, using the holographic entanglement density, we also show that, for
the first time, the saturated value of the entanglement entropy is twice the
Bekenstein-Hawking entropy in doubly holography.Comment: 34 pages, 13 figure
Beyond slurry-cast supercapacitor electrodes: PAN/MWNT heteromat-mediated ultrahigh capacitance electrode sheets
Supercapacitors (SCs) have garnered considerable attention as an appealing power source for forthcoming smart energy era. An ultimate challenge facing the SCs is the acquisition of higher energy density without impairing their other electrochemical properties. Herein, we demonstrate a new class of polyacrylonitrile (PAN)/multi-walled carbon tube (MWNT) heteromat-mediated ultrahigh capacitance electrode sheets as an unusual electrode architecture strategy to address the aforementioned issue. Vanadium pentoxide (V2O5) is chosen as a model electrode material to explore the feasibility of the suggested concept. The heteromat V2O5 electrode sheets are produced through one-pot fabrication based on concurrent electrospraying (for V2O5 precursor/MWNT) and electrospinning (for PAN nanofiber) followed by calcination, leading to compact packing of V2O5 materials in intimate contact with MWNTs and PAN nanofibers. As a consequence, the heteromat V2O5 electrode sheets offer three-dimensionally bicontinuous electron (arising from MWNT networks)/ion (from spatially reticulated interstitial voids to be filled with liquid electrolytes) conduction pathways, thereby facilitating redox reaction kinetics of V2O5 materials. In addition, elimination of heavy metallic foil current collectors, in combination with the dense packing of V2O5 materials, significantly increases (electrode sheet-based) specific capacitances far beyond those accessible with conventional slurry-cast electrodes.ope
Do family values and reproductive health knowledge influence reproductive health-promoting behaviors in married women? A cross-sectional survey
Purpose Based on the World Health Organization framework on reproductive health, this descriptive correlational study investigated the factors affecting reproductive health-promoting behaviors of married women, with a focus on family values and reproductive health knowledge. Methods A cross-sectional survey was conducted on 170 married women between the ages of 25 and 49 years living in Daegu, Korea. The general and reproductive health characteristics, family values, and reproductive health knowledge of married women were identified, as well as factors affecting reproductive health-promoting behaviors. A questionnaire survey was administered to investigate the impact of various factors on reproductive health-promoting behaviors. Results Positive correlations were shown for health promotion behaviors with family values (r=.78, p<.001) and reproductive health knowledge (r=.55, p<.001). Family values (β=.35, p<.001) and reproductive health knowledge (β=.24, p<.001) were identified as factors influencing reproductive health-promoting behaviors. According to the regression model, the explanatory power of factors affecting reproductive health-promoting behaviors among married women was 51.2%. Conclusion A history of reproductive diseases, family values, and reproductive health knowledge were identified as factors influencing reproductive health-promoting behaviors. These results provide basic data for the development of a reproductive health-promoting program, including a positive approach to reproductive health among married women, and can serve as a basis for further research on intervention strategies
Thermal Performance Analysis of Reinforced Concrete Floor Structure with Radiant Floor Heating System in Apartment Housing
The use of the resilient materials in the radiant floor heating systems of reinforced concrete floor in apartment housing is closely related to the reduction of the floor impact sound and the heating energy loss. This study examined the thermal conductivity of expanded polystyrene (EPS) foam used for the resilient material in South Korea and analysed the thermal transfer of reinforced concrete floor structure according to the thermal conductivity of the resilient materials. 82 EPS specimens were used to measure the thermal conductivity. The measured apparent density of EPS resilient materials ranged between 9.5 and 63.0 kg/m3, and the thermal conductivity ranged between 0.030 and 0.046 W/(m·K). As the density of resilient materials made of expanded polystyrene foam increases, the thermal conductivity tends to proportionately decrease. To set up reasonable thermal insulation requirements for radiant heating floor systems, the thermal properties of floor structure according to thermal insulation materials must be determined. Heat transfer simulations were performed to analyze the surface temperature, heat loss, and heat flow of floor structure with radiant heating system. As the thermal conductivity of EPS resilient material increased 1.6 times, the heat loss was of 3.4% increase
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