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  • Publication . Other literature type . Article . 2021
    Open Access
    Authors: 
    Errol Colak; Felipe Kitamura; Stephen B Hobbs; Carol C Wu; Matthew P. Lungren; Luciano M. Prevedello; Jayashree Kalpathy-Cramer; Robyn L Ball; George Shih; Anouk Stein; +20 more
    Publisher: Radiological Society of North America (RSNA)

    This dataset is composed of CT pulmonary angiograms and annotations related to pulmonary embolism. It is available at https://www.rsna.org/education/ai-resources-and-training/ai-image-challenge/rsn...

  • Authors: 
    Xiao-Ping Chen; Wei Hong; Tie Jun Cui; Ke Wu;
    Publisher: Informa UK Limited

    Substrate integrated waveguide (SIW) can be used to implement high Q waveguide components with the same easy and low-cost fabrication process as planar circuits. In this paper two inline three-pole dual-mode filters with asymmetric transmission response based on SIW are presented. These two filters, consisting of a TE102-TE301 dual-mode SIW cavity and a TE101 mode SIW cavity, are centred at around 10 GHz with a transmission zero on the left of the passband and the right of the passband, respectively. Based on the two kinds of three-pole deal-mode filters, a diplexer with isolation better than 35 dB is developed. A linear microstrip taper is used to implement the transition between microstrip and SIW. The measured results agree with simulated results.

  • Open Access
    Authors: 
    Xue Xu; Yuan Zhou; Xiaowen Feng; Xiong Li; Mohammad Asad; Derek Li; Bo Liao; Jianqiang Li; Qinghua Cui; Edwin Wang;
    Publisher: American Association for the Advancement of Science (AAAS)
    Project: NSERC

    There is an ongoing debate on the importance of genetic factors in cancer development, where gene-centered cancer predisposition seems to show that only 5 to 10% of the cancer cases are inheritable. By conducting a systematic analysis of germline genomes of 9712 cancer patients representing 22 common cancer types along with 16,670 noncancer individuals, we identified seven cancer-associated germline genomic patterns (CGGPs), which summarized trinucleotide mutational spectra of germline genomes. A few CGGPs were consistently enriched in the germline genomes of patients whose tumors had smoking signatures or correlated with oncogenesis- and genome instability–related mutations. Furthermore, subgroups defined by the CGGPs were significantly associated with distinct oncogenic pathways, tumor histological subtypes, and prognosis in 13 common cancer types, suggesting that germline genomic patterns enable to inform treatment and clinical outcomes. These results provided evidence that cancer risk and clinical outcomes could be encoded in germline genomes. Germline variants when organized as genomic patterns are associated with cancer risk, oncogenic pathways, and clinical outcomes.

  • Open Access
    Authors: 
    Graeme C. Hays; Luciana C. Ferreira; Ana M. M. Sequeira; Mark G. Meekan; Carlos M. Duarte; Helen Bailey; Fred Bailleul; W. Don Bowen; M. Julian Caley; Daniel P. Costa; +30 more
    Publisher: Elsevier BV
    Countries: Germany, United States, France, United Kingdom, Spain

    It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology. Workshop funding was granted to M.T., A.M.M.S., and C.M.D. by the UWA Oceans Institute, the Australian Institute of Marine Science, and the Office of Sponsored Research at King Abdullah University of Science and Technology (KAUST). Hays, Graeme C. et al. Peer reviewed

  • Open Access
    Authors: 
    Zhan Zhou; Xingfu Zou;
    Publisher: Elsevier BV
    Project: NSERC

    Abstract In this paper, we consider a discrete logistic equation x ( n +1)= x ( n ) exp r ( n ) 1 − x ( n ) K ( n ) where {r(n)} and {K(n)} are positive ω-periodic sequences. Sufficient conditions are obtained for the existence of a positive and globally asymptotically stable ω-periodic solution. Counterexamples are given to illustrate that the conclusions in [1] are incorrect.

  • Open Access
    Authors: 
    Meiling Li; Bassant Selim; Sami Muhaidat; Paschalis C. Sofotasios; Paul D. Yoo; Jie Liang; Anhong Wang;
    Publisher: IEEE
    Country: Finland

    Non-orthogonal multiple access (NOMA) has been proposed as a promising technology that is capable of improving the spectral efficiency of fifth-generation wireless networks and beyond. However, in practical communication scenarios, transceiver architectures inevitably suffer from radio frequency (RF) front-end related impairments that cause non-negligible performance degradation. This issue can be addressed by analog and digital signal processing algorithms, but factors such as time-varying hardware characteristics and imperfect compensation schemes result to detrimental residual distortions. In the present contribution we investigate the physical layer security of NOMA-based amplify-and-forward relay systems under such realistically incurred residual hardware impairment (RHI) effects. Exact and asymptotic analytic expressions for the corresponding outage probability (OP) and intercept probability (IP) of the considered set up over multipath fading channels are derived and corroborated by respective simulation results. Based on this, it is shown that RHI affects both the legitimate users and eavesdroppers by increasing the OP and decreasing the IP. For a fixed OP, RHI generally increases the corresponding IP, thereby reducing the secure performance of the system. Further interesting insights are also provided, verifying the importance of the offered results for the effective design and deployment of secure cooperative communication systems. acceptedVersion Peer reviewed

  • Closed Access
    Authors: 
    Yulei Sui; Qingxia Liu; Tao Jiang; Yufeng Guo;
    Publisher: Elsevier BV

    Abstract For the first time, a one-step synthetic strategy has been developed towards the preparation of Ti3+ self-doped TiO2 with internal-pores and highly exposed {001} facets using ethylene glycol (EG) and HF as control agents. The obtained samples were characterized by XRD, XPS, SEM, TEM, HAADF-STEM, photoluminescence spectroscopy (PL), and UV–vis reflectance spectroscopy. The synergistic effect of EG and HF plays a vital role in the formation of synthesized TiO2 with Ti3+ self-doping, internal-pores and highly exposed {001} facets. As-synthesized TiO2 exhibit much higher activity than commercial P25 on photocatalytic degradation of phenol and the outstanding performance is attributed to the synergistic effect of Ti3+ doping, internal-pores, and facets heterojunction.

  • Open Access
    Authors: 
    Gonzalo Sánchez; Rafael K. Varaschin; Hansruedi Büeler; Paul C. Marcogliese; David S. Park; Louis-Eric Trudeau;
    Publisher: Public Library of Science (PLoS)

    Parkinson's disease (PD) is one of the most prevalent neurodegenerative brain diseases; it is accompanied by extensive loss of dopamine (DA) neurons of the substantia nigra that project to the putamen, leading to impaired motor functions. Several genes have been associated with hereditary forms of the disease and transgenic mice have been developed by a number of groups to produce animal models of PD and to explore the basic functions of these genes. Surprisingly, most of the various mouse lines generated such as Parkin KO, Pink1 KO, DJ-1 KO and LRRK2 transgenic have been reported to lack degeneration of nigral DA neuron, one of the hallmarks of PD. However, modest impairments of motor behavior have been reported, suggesting the possibility that the models recapitulate at least some of the early stages of PD, including early dysfunction of DA axon terminals. To further evaluate this possibility, here we provide for the first time a systematic comparison of DA release in four different mouse lines, examined at a young age range, prior to potential age-dependent compensations. Using fast scan cyclic voltammetry in striatal sections prepared from young, 6-8 weeks old mice, we examined sub-second DA overflow evoked by single pulses and action potential trains. Unexpectedly, none of the models displayed any dysfunction of DA overflow or reuptake. These results, compatible with the lack of DA neuron loss in these models, suggest that molecular dysfunctions caused by the absence or mutation of these individual genes are not sufficient to perturb the function and survival of mouse DA neurons.

  • Authors: 
    Jinyan Dong; Lei Zhang; Jiaqi Zhou; Weiwei Pan; Xijia Gu; Yan Feng;
    Publisher: The Optical Society

    An over 200 W high-power first-order random Raman fiber laser (RRFL) at 1238 nm is demonstrated. The laser is based on a half-open cavity with a piece of 30 m phosphosilicate fiber. This RRFL is pumped by a conventional 1064 nm Yb-doped fiber laser. After suppressing the silica Raman component, a maximum output power of 206.7 W is obtained with a full width half-maximum linewidth of 7.1 nm at a pump power of 346.3 W, corresponding to an optical-to-optical efficiency of 59.7%. To the best of our knowledge, this is the highest reported output power of RRFL on the basis of phosphosilicate fiber with the shortest cavity length.

  • Closed Access
    Authors: 
    Sangwoo Chung; Duncan J. Mowbray; Zoran L. Mišković; Frank O. Goodman; You-Nian Wang;
    Publisher: Elsevier BV

    Abstract We use a two-fluid hydrodynamic model to describe the dielectric response of the σ and π electron systems on a multiwalled carbon nanotube consisting of up to several tens of concentric cylindrical shells. In particular, we evaluate the stopping power and the dynamical image potential for ions moving parallel to the nanotube axis. It is found that both quantities are profoundly affected by the increasing number of nanotube shells, as a consequence of the rich plasmon spectra developed due to the inter- and intra-shell electrostatic interactions between the electron systems.

Include:
147,554 Research products, page 1 of 14,756
  • Publication . Other literature type . Article . 2021
    Open Access
    Authors: 
    Errol Colak; Felipe Kitamura; Stephen B Hobbs; Carol C Wu; Matthew P. Lungren; Luciano M. Prevedello; Jayashree Kalpathy-Cramer; Robyn L Ball; George Shih; Anouk Stein; +20 more
    Publisher: Radiological Society of North America (RSNA)

    This dataset is composed of CT pulmonary angiograms and annotations related to pulmonary embolism. It is available at https://www.rsna.org/education/ai-resources-and-training/ai-image-challenge/rsn...

  • Authors: 
    Xiao-Ping Chen; Wei Hong; Tie Jun Cui; Ke Wu;
    Publisher: Informa UK Limited

    Substrate integrated waveguide (SIW) can be used to implement high Q waveguide components with the same easy and low-cost fabrication process as planar circuits. In this paper two inline three-pole dual-mode filters with asymmetric transmission response based on SIW are presented. These two filters, consisting of a TE102-TE301 dual-mode SIW cavity and a TE101 mode SIW cavity, are centred at around 10 GHz with a transmission zero on the left of the passband and the right of the passband, respectively. Based on the two kinds of three-pole deal-mode filters, a diplexer with isolation better than 35 dB is developed. A linear microstrip taper is used to implement the transition between microstrip and SIW. The measured results agree with simulated results.

  • Open Access
    Authors: 
    Xue Xu; Yuan Zhou; Xiaowen Feng; Xiong Li; Mohammad Asad; Derek Li; Bo Liao; Jianqiang Li; Qinghua Cui; Edwin Wang;
    Publisher: American Association for the Advancement of Science (AAAS)
    Project: NSERC

    There is an ongoing debate on the importance of genetic factors in cancer development, where gene-centered cancer predisposition seems to show that only 5 to 10% of the cancer cases are inheritable. By conducting a systematic analysis of germline genomes of 9712 cancer patients representing 22 common cancer types along with 16,670 noncancer individuals, we identified seven cancer-associated germline genomic patterns (CGGPs), which summarized trinucleotide mutational spectra of germline genomes. A few CGGPs were consistently enriched in the germline genomes of patients whose tumors had smoking signatures or correlated with oncogenesis- and genome instability–related mutations. Furthermore, subgroups defined by the CGGPs were significantly associated with distinct oncogenic pathways, tumor histological subtypes, and prognosis in 13 common cancer types, suggesting that germline genomic patterns enable to inform treatment and clinical outcomes. These results provided evidence that cancer risk and clinical outcomes could be encoded in germline genomes. Germline variants when organized as genomic patterns are associated with cancer risk, oncogenic pathways, and clinical outcomes.

  • Open Access
    Authors: 
    Graeme C. Hays; Luciana C. Ferreira; Ana M. M. Sequeira; Mark G. Meekan; Carlos M. Duarte; Helen Bailey; Fred Bailleul; W. Don Bowen; M. Julian Caley; Daniel P. Costa; +30 more
    Publisher: Elsevier BV
    Countries: Germany, United States, France, United Kingdom, Spain

    It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical developments and led to fundamental discoveries in the field. We show that the questions have broad applicability to other taxa, including terrestrial animals, flying insects, and swimming invertebrates, and, as such, this exercise provides a useful roadmap for targeted deployments and data syntheses that should advance the field of movement ecology. Workshop funding was granted to M.T., A.M.M.S., and C.M.D. by the UWA Oceans Institute, the Australian Institute of Marine Science, and the Office of Sponsored Research at King Abdullah University of Science and Technology (KAUST). Hays, Graeme C. et al. Peer reviewed

  • Open Access
    Authors: 
    Zhan Zhou; Xingfu Zou;
    Publisher: Elsevier BV
    Project: NSERC

    Abstract In this paper, we consider a discrete logistic equation x ( n +1)= x ( n ) exp r ( n ) 1 − x ( n ) K ( n ) where {r(n)} and {K(n)} are positive ω-periodic sequences. Sufficient conditions are obtained for the existence of a positive and globally asymptotically stable ω-periodic solution. Counterexamples are given to illustrate that the conclusions in [1] are incorrect.

  • Open Access
    Authors: 
    Meiling Li; Bassant Selim; Sami Muhaidat; Paschalis C. Sofotasios; Paul D. Yoo; Jie Liang; Anhong Wang;
    Publisher: IEEE
    Country: Finland

    Non-orthogonal multiple access (NOMA) has been proposed as a promising technology that is capable of improving the spectral efficiency of fifth-generation wireless networks and beyond. However, in practical communication scenarios, transceiver architectures inevitably suffer from radio frequency (RF) front-end related impairments that cause non-negligible performance degradation. This issue can be addressed by analog and digital signal processing algorithms, but factors such as time-varying hardware characteristics and imperfect compensation schemes result to detrimental residual distortions. In the present contribution we investigate the physical layer security of NOMA-based amplify-and-forward relay systems under such realistically incurred residual hardware impairment (RHI) effects. Exact and asymptotic analytic expressions for the corresponding outage probability (OP) and intercept probability (IP) of the considered set up over multipath fading channels are derived and corroborated by respective simulation results. Based on this, it is shown that RHI affects both the legitimate users and eavesdroppers by increasing the OP and decreasing the IP. For a fixed OP, RHI generally increases the corresponding IP, thereby reducing the secure performance of the system. Further interesting insights are also provided, verifying the importance of the offered results for the effective design and deployment of secure cooperative communication systems. acceptedVersion Peer reviewed

  • Closed Access
    Authors: 
    Yulei Sui; Qingxia Liu; Tao Jiang; Yufeng Guo;
    Publisher: Elsevier BV

    Abstract For the first time, a one-step synthetic strategy has been developed towards the preparation of Ti3+ self-doped TiO2 with internal-pores and highly exposed {001} facets using ethylene glycol (EG) and HF as control agents. The obtained samples were characterized by XRD, XPS, SEM, TEM, HAADF-STEM, photoluminescence spectroscopy (PL), and UV–vis reflectance spectroscopy. The synergistic effect of EG and HF plays a vital role in the formation of synthesized TiO2 with Ti3+ self-doping, internal-pores and highly exposed {001} facets. As-synthesized TiO2 exhibit much higher activity than commercial P25 on photocatalytic degradation of phenol and the outstanding performance is attributed to the synergistic effect of Ti3+ doping, internal-pores, and facets heterojunction.

  • Open Access
    Authors: 
    Gonzalo Sánchez; Rafael K. Varaschin; Hansruedi Büeler; Paul C. Marcogliese; David S. Park; Louis-Eric Trudeau;
    Publisher: Public Library of Science (PLoS)

    Parkinson's disease (PD) is one of the most prevalent neurodegenerative brain diseases; it is accompanied by extensive loss of dopamine (DA) neurons of the substantia nigra that project to the putamen, leading to impaired motor functions. Several genes have been associated with hereditary forms of the disease and transgenic mice have been developed by a number of groups to produce animal models of PD and to explore the basic functions of these genes. Surprisingly, most of the various mouse lines generated such as Parkin KO, Pink1 KO, DJ-1 KO and LRRK2 transgenic have been reported to lack degeneration of nigral DA neuron, one of the hallmarks of PD. However, modest impairments of motor behavior have been reported, suggesting the possibility that the models recapitulate at least some of the early stages of PD, including early dysfunction of DA axon terminals. To further evaluate this possibility, here we provide for the first time a systematic comparison of DA release in four different mouse lines, examined at a young age range, prior to potential age-dependent compensations. Using fast scan cyclic voltammetry in striatal sections prepared from young, 6-8 weeks old mice, we examined sub-second DA overflow evoked by single pulses and action potential trains. Unexpectedly, none of the models displayed any dysfunction of DA overflow or reuptake. These results, compatible with the lack of DA neuron loss in these models, suggest that molecular dysfunctions caused by the absence or mutation of these individual genes are not sufficient to perturb the function and survival of mouse DA neurons.

  • Authors: 
    Jinyan Dong; Lei Zhang; Jiaqi Zhou; Weiwei Pan; Xijia Gu; Yan Feng;
    Publisher: The Optical Society

    An over 200 W high-power first-order random Raman fiber laser (RRFL) at 1238 nm is demonstrated. The laser is based on a half-open cavity with a piece of 30 m phosphosilicate fiber. This RRFL is pumped by a conventional 1064 nm Yb-doped fiber laser. After suppressing the silica Raman component, a maximum output power of 206.7 W is obtained with a full width half-maximum linewidth of 7.1 nm at a pump power of 346.3 W, corresponding to an optical-to-optical efficiency of 59.7%. To the best of our knowledge, this is the highest reported output power of RRFL on the basis of phosphosilicate fiber with the shortest cavity length.

  • Closed Access
    Authors: 
    Sangwoo Chung; Duncan J. Mowbray; Zoran L. Mišković; Frank O. Goodman; You-Nian Wang;
    Publisher: Elsevier BV

    Abstract We use a two-fluid hydrodynamic model to describe the dielectric response of the σ and π electron systems on a multiwalled carbon nanotube consisting of up to several tens of concentric cylindrical shells. In particular, we evaluate the stopping power and the dynamical image potential for ions moving parallel to the nanotube axis. It is found that both quantities are profoundly affected by the increasing number of nanotube shells, as a consequence of the rich plasmon spectra developed due to the inter- and intra-shell electrostatic interactions between the electron systems.