Radiotracer experiments on diffusion of 63Ni and 86Rb in severely deformed commercially pure copper (8 passes of equal channel angular pressing) reveal unambiguously the existence of ultrafast transport paths. A fraction of these paths remains in the material even after complete recrystallization. Scanning electron microscopy and focused ion beam techniques are applied. Deep grooves are found which are related to original high-energy interfaces. In-depth sectioning near corresponding triple junctions reveals clearly multiple microvoids or microcracks caused by the severe deformation. Long-range tracer penetration over tens of micrometers proves that these submicrometer-large defects are connected by highly diffusive paths and that they appear with significant frequency.
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http://dx.doi.org/10.1103/PhysRevLett.102.165501 | DOI Listing |
Geomorphology (Amst)
December 2024
Retired: U.S. Environmental Protection Agency, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, 200 SW 35th Street, Corvallis, OR 97333, USA.
Reliable estimates of low flow and flood discharge at ungaged locations are required for evaluating stream flow alteration, designing culverts and stream crossings, and interpreting regional surveys of habitat and biotic condition. Very few stream gaging stations are located on small, remote streams, which typically have complex channel morphology. Adequate gaging is also lacking on larger streams that are remote, smaller than those typically gaged, or have channel morphology not conducive to installation of gages.
View Article and Find Full Text PDFInt J Parasitol Drugs Drug Resist
December 2024
São Paulo State University (Unesp), School of Pharmaceutical Sciences, Araraquara, São Paulo, Brazil. Electronic address:
Leishmaniasis is a neglected disease that remains with a limited number of drugs available for chemotherapy and has an increased drug resistance that affects treatment outcomes. Metal-based drugs such as cyclopalladated complex [Pd(dmba)(μ-N)] (CP2), a Leishmania topoisomerase IB inhibitor involved in calcium dysregulation and mitochondrial dysfunction of the parasite, had been an alternative to outline the appearance of chemoresistance. To identify new molecular targets and point out possible resistance mechanisms, a CP2-resistant Leishmania amazonensis (LaR) was selected by stepwise exposure to increasing drug pressure until a line capable of growth in 13.
View Article and Find Full Text PDFSci Rep
December 2024
Department of Computer Science and Digital Technologies, University of East London, London, UK.
Nursing activity recognition has immense importance in the development of smart healthcare management and is an extremely challenging area of research in human activity recognition. The main reasons are an extreme class-imbalance problem and intra-class variability depending on both the subject and the recipient. In this paper, we apply a unique two-step feature extraction, coupled with an intermediate feature 'Angle' and a new feature called mean min max sum to render the features robust against intra-class variation.
View Article and Find Full Text PDFBMC Oral Health
December 2024
Department of Prosthodontics, Faculty of Dentistry, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand.
Background: The selection guideline for the implant-supported bar connectors (ISBC) of hybrid denture is lacking. This study investigated the maximum von Mises stress (vMS), stress distribution, and displacement of various geometric ISBC in mandibular hybrid dentures, as well as the maximum principal stress (σmax) in the acrylic resin part, through finite element analysis.
Methods: Four different geometric cross-sectional patterns for mandibular ISBC-L, Y, I, and Square-of equal volume, based on the "All-on-4" concept, were created.
Commonly used linear equalizers in optical transmissions may induce in-band noise enhancement in the high-frequency region, degrading signaling performance. In this Letter, we propose for the first, to our knowledge, time, to mitigate the multi-input-multi-output (MIMO) equalizer-enhanced noise (EEN) in coupled-core multicore fiber (CC-MCF) systems by utilizing the spectral shaping (SS) filter and maximum likelihood sequence detection (MLSD), which have shown effective EEN mitigation in SMF systems. However, CC-MCF systems feature multiple spatial channels, each requiring separate coefficient optimization for SS filters corresponding to each output of MIMO.
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