100 research outputs found
The number of edges in a maximum cycle—distributed graph
AbstractLet f(n) (f2(n)) be the maximum possible number of edges in a graph (2-connected simple graph) on n vertices in which no two cycles have the same length. In this note, we prove that, for every integer n ⩾ 3, f(n) ⩾ n + k + [(12(8n − 24k2 + 8k − 7 − 1)] where k = [121(21n − 26 + 11)] and obtain upper and lower bounds on f2(n)
Noise Induced Hearing Loss in Children: Preventing the Silent Epidemic
Noise-induced hearing loss and related tinnitus are often unrecognized problems, especially in non-occupational settings. Research indicates that increasing numbers of children and adolescents have or are acquiring noise induced hearing losses. Noise induced hearing loss can almost completely be prevented with simple precautionary measures. Educational programs rarely exist outside of those mandated in occupational settings. Health Communication theory can be applied to hearing health for developing effective loss prevention programs. Dangerous Decibels is one example of an effective multi-disciplinary effort to develop and disseminated prevention strategies
Planar carbon nanotube-graphene hybrid films for high-performance broadband photodetectors
Graphene has emerged as a promising material for photonic applications
fuelled by its superior electronic and optical properties. However, the
photoresponsivity is limited by the low absorption cross section and ultrafast
recombination rates of photoexcited carriers. Here we demonstrate a
photoconductive gain of 10 electrons per photon in a carbon
nanotube-graphene one dimensional-two dimensional hybrid due to efficient
photocarriers generation and transport within the nanostructure. A broadband
photodetector (covering 400 nm to 1550 nm) based on such hybrid films is
fabricated with a high photoresponsivity of more than 100 AW and a fast
response time of approximately 100 {\mu}s. The combination of ultra-broad
bandwidth, high responsivities and fast operating speeds affords new
opportunities for facile and scalable fabrication of all-carbon optoelectronic
devices.Comment: 21 pages, 3 figure
A High-Performance Mid-infrared Optical Switch Enabled by Bulk Dirac Fermions in Cd3As2
Pulsed lasers operating in the 2-5 {\mu}m band are important for a wide range
of applications in sensing, spectroscopy, imaging and communications. Despite
recent advances with mid-infrared gain media, the lack of a capable pulse
generation mechanism, i.e. a passive optical switch, remains a significant
technological challenge. Here we show that mid-infrared optical response of
Dirac states in crystalline Cd3As2, a three-dimensional topological Dirac
semimetal (TDS), constitutes an ideal ultrafast optical switching mechanism for
the 2-5 {\mu}m range. Significantly, fundamental aspects of the photocarrier
processes, such as relaxation time scales, are found to be flexibly controlled
through element doping, a feature crucial for the development of convenient
mid-infrared ultrafast sources. Although various exotic physical phenomena have
been uncovered in three-dimensional TDS systems, our findings show for the
first time that this emerging class of quantum materials can be harnessed to
fill a long known gap in the field of photonics.Comment: 17 pages, 3 figure
Breast Cancer Immunohistochemical Image Generation: a Benchmark Dataset and Challenge Review
For invasive breast cancer, immunohistochemical (IHC) techniques are often
used to detect the expression level of human epidermal growth factor receptor-2
(HER2) in breast tissue to formulate a precise treatment plan. From the
perspective of saving manpower, material and time costs, directly generating
IHC-stained images from hematoxylin and eosin (H&E) stained images is a
valuable research direction. Therefore, we held the breast cancer
immunohistochemical image generation challenge, aiming to explore novel ideas
of deep learning technology in pathological image generation and promote
research in this field. The challenge provided registered H&E and IHC-stained
image pairs, and participants were required to use these images to train a
model that can directly generate IHC-stained images from corresponding
H&E-stained images. We selected and reviewed the five highest-ranking methods
based on their PSNR and SSIM metrics, while also providing overviews of the
corresponding pipelines and implementations. In this paper, we further analyze
the current limitations in the field of breast cancer immunohistochemical image
generation and forecast the future development of this field. We hope that the
released dataset and the challenge will inspire more scholars to jointly study
higher-quality IHC-stained image generation.Comment: 13 pages, 11 figures, 2table
Spin-ARPES EUV beamline for ultrafast materials research and development
A new femtosecond, Extreme Ultraviolet (EUV), Time Resolved Spin-Angle Resolved Photo-Emission Spectroscopy (TR-Spin-ARPES) beamline was developed for ultrafast materials research and development. This 50-fs laser-driven, table-top beamline is an integral part of the "Ultrafast Spintronic Materials Facility", dedicated to engineering ultrafast materials. This facility provides a fast and in-situ analysis and development of new materials. The EUV source based on high harmonic generation process emits 2.3 × 1011 photons/second (2.3 × 108 photons/pulse) at H23 (35.7 eV) and its photon energy ranges from 10 eV to 75 eV, which enables surface sensitive studies of the electronic structure dynamics. The EUV monochromator provides the narrow bandwidth of the EUV beamline while preserving its pulse duration in an energy range of 10-100 eV. Ultrafast surface photovoltaic effect with ~650 fs rise-time was observed in p-GaAs (100) from time-resolved ARPES spectra. The data acquisition time could be reduced by over two orders of magnitude by scaling the laser driver from 1 KHz, 4W to MHz, KW average power
The 5p15.33 Locus Is Associated with Risk of Lung Adenocarcinoma in Never-Smoking Females in Asia
Genome-wide association studies of lung cancer reported in populations of European background have identified three regions on chromosomes 5p15.33, 6p21.33, and 15q25 that have achieved genome-wide significance with p-values of 10−7 or lower. These studies have been performed primarily in cigarette smokers, raising the possibility that the observed associations could be related to tobacco use, lung carcinogenesis, or both. Since most women in Asia do not smoke, we conducted a genome-wide association study of lung adenocarcinoma in never-smoking females (584 cases, 585 controls) among Han Chinese in Taiwan and found that the most significant association was for rs2736100 on chromosome 5p15.33 (p = 1.30×10−11). This finding was independently replicated in seven studies from East Asia totaling 1,164 lung adenocarcinomas and 1,736 controls (p = 5.38×10−11). A pooled analysis achieved genome-wide significance for rs2736100. This SNP marker localizes to the CLPTM1L-TERT locus on chromosome 5p15.33 (p = 2.60×10−20, allelic risk = 1.54, 95% Confidence Interval (CI) 1.41–1.68). Risks for heterozygote and homozygote carriers of the minor allele were 1.62 (95% CI; 1.40–1.87), and 2.35 (95% CI: 1.95–2.83), respectively. In summary, our results show that genetic variation in the CLPTM1L-TERT locus of chromosome 5p15.33 is directly associated with the risk of lung cancer, most notably adenocarcinoma
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