| 1. |
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| 2. |
- Kristanl, Matej, et al.
(author)
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The Seventh Visual Object Tracking VOT2019 Challenge Results
- 2019
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In: 2019 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW). - : IEEE COMPUTER SOC. - 9781728150239 ; , s. 2206-2241
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Conference paper (peer-reviewed)abstract
- The Visual Object Tracking challenge VOT2019 is the seventh annual tracker benchmarking activity organized by the VOT initiative. Results of 81 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in the recent years. The evaluation included the standard VOT and other popular methodologies for short-term tracking analysis as well as the standard VOT methodology for long-term tracking analysis. The VOT2019 challenge was composed of five challenges focusing on different tracking domains: (i) VOT-ST2019 challenge focused on short-term tracking in RGB, (ii) VOT-RT2019 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2019 focused on long-term tracking namely coping with target disappearance and reappearance. Two new challenges have been introduced: (iv) VOT-RGBT2019 challenge focused on short-term tracking in RGB and thermal imagery and (v) VOT-RGBD2019 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2019, VOT-RT2019 and VOT-LT2019 datasets were refreshed while new datasets were introduced for VOT-RGBT2019 and VOT-RGBD2019. The VOT toolkit has been updated to support both standard short-term, long-term tracking and tracking with multi-channel imagery. Performance of the tested trackers typically by far exceeds standard baselines. The source code for most of the trackers is publicly available from the VOT page. The dataset, the evaluation kit and the results are publicly available at the challenge website(1).
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| 3. |
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| 4. |
- Hu, Jinhong, et al.
(author)
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Safety and immunogenicity of a malaria vaccine, Plasmodium falciparum AMA-1/MSP-1 chimeric protein formulated in montanide ISA 720 in healthy adults
- 2008
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In: PLOS ONE. - : PLOS. - 1932-6203. ; 3:4
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Journal article (peer-reviewed)abstract
- BACKGROUND: The P. falciparum chimeric protein 2.9 (PfCP-2.9) consisting of the sequences of MSP1-19 and AMA-1 (III) is a malaria vaccine candidate that was found to induce inhibitory antibodies in rabbits and monkeys. This was a phase I randomized, single-blind, placebo-controlled, dose-escalation study to evaluate the safety and immunogenicity of the PfCP-2.9 formulated with a novel adjuvant Montanide ISA720. Fifty-two subjects were randomly assigned to 4 dose groups of 10 participants, each receiving the test vaccine of 20, 50, 100, or 200 microg respectively, and 1 placebo group of 12 participants receiving the adjuvant only.METHODS AND FINDINGS: The vaccine formulation was shown to be safe and well-tolerated, and none of the participants withdrew. The total incidence of local adverse events (AEs) was 75%, distributed among 58% of the placebo group and 80% of those vaccinated. Among the vaccinated, 65% had events that were mild and 15% experienced moderate AEs. Almost all systemic adverse reactions observed in this study were graded as mild and required no therapy. The participants receiving the test vaccine developed detectable antibody responses which were boosted by the repeated vaccinations. Sixty percent of the vaccinated participants had high ELISA titers (>1:10,000) of antigen-specific antibodies which could also recognize native parasite proteins in an immunofluorescence assay (IFA).CONCLUSION: This study is the first clinical trial for this candidate and builds on previous investigations supporting PfCP-2.9/ISA720 as a promising blood-stage malaria vaccine. Results demonstrate safety, tolerability (particularly at the lower doses tested) and immunogenicity of the formulation. Further clinical development is ongoing to explore optimizing the dose and schedule of the formulation to decrease reactogenicity without compromising immunogenicity.TRIAL REGISTRATION: Chinese State Food and Drug Administration (SFDA) 2002SL0046; Controlled-Trials.com ISRCTN66850051 [66850051].
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| 5. |
- Wang, Yuhang, et al.
(author)
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Purification and characterization of recombinant human bile salt-stimulated lipase expressed in milk of transgenic cloned cows
- 2017
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In: PLOS ONE. - : PUBLIC LIBRARY SCIENCE. - 1932-6203. ; 12:5
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Journal article (peer-reviewed)abstract
- Bile salt-stimulated lipase (BSSL) is a lipolytic digestive enzyme with broad substrate specificity secreted from exocrine pancreas into the intestinal lumen in all species and from the lactating mammary gland into the milk of some species, notably humans but not cows. BSSL in breast milk facilitates digestion and absorption of milk fat and promotes growth of small for gestational age preterm infants. Thus, purified recombinant human BSSL (rhBSSL) can be used for treatment of patients with fat malabsorption and expressing rhBSSL in the milk of transgenic cloned cows would therefore be a mean to meet a medical need. In the present study, a vector pBAC-hLF-hBSSL was constructed, which efficiently expressed active rhBSSL in milk of transgenic cloned cows to a concentration of 9.8 mg/ml. The rhBSSL purified from cow milk had the same enzymatic activity, N-terminal amino acid sequence, amino acid composition and isoelectric point and similar physicochemical characteristics as human native BSSL. Our study supports the use of transgenic cattle for the cost-competitive, large-scale production of therapeutic rhBSSL.
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| 6. |
- Li, Duan, et al.
(author)
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Sinterability of the oxynitride LaTiO2N with perovskite-type structure
- 2014
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In: Journal of Alloys and Compounds. - : Elsevier BV. - 0925-8388 .- 1873-4669. ; 586, s. 567-573
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Journal article (peer-reviewed)abstract
- Based on a thermal stability study, the sinterability of the oxynitride LaTiO2N was investigated by spark plasma sintering (SPS). The results show that LaTiO2N is thermodynamically unstable above ca. 400 degrees C in air and ca. 800 degrees C in argon. While it appears impossible to completely avoid decomposition during sintering, LaTiO2N ceramics with relative density of 74-94% and a residual LaTiO2N content of 57-90 wt% were prepared. By manipulating kinetics, a relative density of 94% was achieved at 1350 degrees C under an uniaxially applied pressure of 125 MPa. This density is higher than any other counterparts prepared by conventional sintering so far. SPS appears a feasible tool for manipulating the sintering kinetics. It enables the preparation of almost dense LaTiO2N bulks with adequate purity.
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| 7. |
- Li, Wenjie, et al.
(author)
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A study on the thermal conversion of scheelite-type ABO(4) into perovskite-type AB(O,N)(3)
- 2015
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In: Dalton Transactions. - : Royal Society of Chemistry (RSC). - 1477-9226 .- 1477-9234. ; 44:17, s. 8238-8246
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Journal article (peer-reviewed)abstract
- Phase-pure scheelite AMoO(4) and AWO(4) (A = Ba, Sr, Ca) were thermally treated under an ammonia atmosphere at 400 to 900 degrees C. SrMoO4 and SrWO4 were shown to convert into cubic perovskite SrMoO2N and SrWO1.5N1.5, at 700 degrees C and 900 degrees C respectively, and to form metastable intermediate phases (scheelite SrMoO4-xNx and SrWO4-xNx), as revealed by X-ray diffraction (XRD), elemental analysis and FTIR spectroscopy. High-temperature oxide melt solution calorimetry reveals that the enthalpy of formation for SrM(O,N)(3) (M = Mo, W) perovskites is less negative than that of the corresponding scheelite oxides, though the conversion of the scheelite oxides into perovskite oxynitrides is thermodynamically favorable at moderate temperatures. The reaction of BaMO4 with ammonia leads to the formation of rhombohedral Ba3M2(O,N)(8) and the corresponding binary metal nitrides Mo3N2 and W4.6N4; similar behavior was observed for CaMO4, which converted upon ammonolysis into individual oxides and nitrides. Thus, BaMO4 and CaMO4 were shown to not provide access to perovskite oxynitrides. The influence of the starting scheelite oxide precursor, the structure distortion and the degree of covalency of the B-site-N bond are discussed within the context of the formability of perovskite oxynitrides.
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| 8. |
- Li, Wenjie, et al.
(author)
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Synthesis and rapid sintering of dense SrA(O,N)(3) (A = Mo, W) oxynitride ceramics
- 2015
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In: Journal of the European Ceramic Society. - : Elsevier BV. - 0955-2219 .- 1873-619X. ; 35:12, s. 3273-3281
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Journal article (peer-reviewed)abstract
- SrMo(O,N)(3) and SrW(O,N)(3) oxynitride powders were synthesized via a solvothermal route followed by ammonolysis. Their rapid densification by spark plasma sintering with a heating rate of 300-400 degrees C/min under a uniaxial pressure of 100 MPa yielded dense monoliths. The lowest open porosity achieved was 0 vol% for SrMo(O,N)(3) and 7.6 vol% for SrW(O,N)(3). The compacted monoliths were characterized by elemental analysis, electron microscopy (SEM, TEM) coupled with energy dispersive X-ray spectroscopy (EDX), as well as X-ray diffraction (XRD). Rietveld refinement of the XRD patterns revealed in the case of the compacted SrMo(O,N)(3) the formation of small amount of ternary oxides (Sr3Mo2O7/SrMoO4/Sr3MoO6), molybdenum nitride (MO2N), as well as metallic Mo. On the contrary, SrW(O,N)(3) exhibited significant decomposition after consolidation, with SrWO4/Sr3WO6 being main components beside SrMo(O,N)(3), accompanied by tungsten nitride (WN) and metallic W. Thus, rapid SPS enables the densification of oxynitrides with high density and acceptable purity that were hardly achieved earlier.
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| 9. |
- Li, Xiangyu, et al.
(author)
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Two-phase flow patterns identification in porous media using feature extraction and SVM
- 2022
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In: International Journal of Multiphase Flow. - : Elsevier BV. - 0301-9322 .- 1879-3533. ; 156
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Journal article (peer-reviewed)abstract
- Rapid and accurate identification of two-phase flow patterns in porous media is of great significance to the chemical industry, petroleum and nuclear engineering, etc. Based on the different pressure signals of gas-liquid two-phase flow in a porous bed, the present work proposes an intelligent recognition method to identify the two-phase flow patterns in porous media by the technologies of feature extraction and support vector machine (SVM). The analysis techniques, including time domain (PDF), frequency domain (PSD) and time-frequency domain (Wavelet), are employed to extract and summarize the corresponding characteristics of differential pressure signals of flow patterns. The intelligent recognition models are developed to identify the two-phase flow patterns in porous media by SVM. The models are trained respectively based on the characteristics of time domain + frequency domain (TF-SVM model), time domain + wavelet (TW-SVM model) and frequency domain + wavelet (FW-SVM model). The overall identification accuracy of the optimal model (TW-SVM model) reaches 96.08%.
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| 10. |
- Miao, Yanfeng, et al.
(author)
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Stable and bright formamidinium-based perovskite light-emitting diodes with high energy conversion efficiency
- 2019
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In: Nature Communications. - : NATURE PUBLISHING GROUP. - 2041-1723. ; 10
-
Journal article (peer-reviewed)abstract
- Solution-processable perovskites show highly emissive and good charge transport, making them attractive for low-cost light-emitting diodes (LEDs) with high energy conversion efficiencies. Despite recent advances in device efficiency, the stability of perovskite LEDs is still a major obstacle. Here, we demonstrate stable and bright perovskite LEDs with high energy conversion efficiencies by optimizing formamidinium lead iodide films. Our LEDs show an energy conversion efficiency of 10.7%, and an external quantum efficiency of 14.2% without outcoupling enhancement through controlling the concentration of the precursor solutions. The device shows low efficiency droop, i.e. 8.3% energy conversion efficiency and 14.0% external quantum efficiency at a current density of 300 mA cm(-2), making the device more efficient than state-of-the-art organic and quantum-dot LEDs at high current densities. Furthermore, the half-lifetime of device with benzylamine treatment is 23.7 hr under a current density of 100 mA cm(-2), comparable to the lifetime of near-infrared organic LEDs.
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| 11. |
- Parra Bravo, Celeste, et al.
(author)
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Human iPSC 4R tauopathy model uncovers modifiers of tau propagation.
- 2024
-
In: Cell. - 1097-4172. ; 187:10
-
Journal article (peer-reviewed)abstract
- Tauopathies are age-associated neurodegenerative diseases whose mechanistic underpinnings remain elusive, partially due to a lack of appropriate human models. Here, we engineered human induced pluripotent stem cell (hiPSC)-derived neuronal lines to express 4R Tau and 4R Tau carrying the P301S MAPT mutation when differentiated into neurons. 4R-P301S neurons display progressive Tau inclusions upon seeding with Tau fibrils and recapitulate features of tauopathy phenotypes including shared transcriptomic signatures, autophagic body accumulation, and reduced neuronal activity. A CRISPRi screen of genes associated with Tau pathobiology identified over 500 genetic modifiers of seeding-induced Tau propagation, including retromer VPS29 and genes in the UFMylation cascade. In progressive supranuclear palsy (PSP) and Alzheimer's Disease (AD) brains, the UFMylation cascade is altered in neurofibrillary-tangle-bearing neurons. Inhibiting the UFMylation cascade invitro and invivo suppressed seeding-induced Tau propagation. This model provides a robust platform to identify novel therapeutic strategies for 4R tauopathy.
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| 12. |
- Zhang, Zhenzong, et al.
(author)
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Tungsten oxide quantum dots deposited onto ultrathin CdIn2S4 nanosheets for efficient S-scheme photocatalytic CO2 reduction via cascade charge transfer
- 2021
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In: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947. ; 428
-
Journal article (peer-reviewed)abstract
- A novel S-scheme photocatalytic heterojunction composite nanomaterial is developed by integrating zero-dimensional WO3 quantum dots (WQDs) on two-dimensional ultrathin CdIn2S4 (CIS) nanosheets with the aim of fostering carrier separation, enhancing the performance of carrier interface transport, minimizing carrier distance transport, and achieving effective photocatalytic CO2 reduction. The composite photocatalyst WQDs/CdIn2S4 (WCIS) allows for the efficient photocatalytic reduction of CO2 to CO and CH4, as shown by product analysis and isotopic measurement. The photogenerated electrons in WQDs recombine with the holes in CIS nanosheets, and the left electrons in CIS have stronger CO2 reduction abilities. The highest yields of CO and CH4 achieved with the WCIS photocatalyst are 8.2 and 1.6 μmol g-1h−1 ––2.6 and 8 times higher than those for CIS, respectively. Moreover, the S-scheme WCIS possesses a stable crystal structure and recycling ability. Finally, the S-scheme charge transfer path on the WCIS composite is proposed according to theoretical calculation, in-situ irradiated X-ray photoelectron spectroscopy, and electron paramagnetic resonance (ESR) analyses.
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| 13. |
- Zhang, Zhenzong, et al.
(author)
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Unveiling the role of Ag-Sb bimetallic S-scheme heterojunction for vis-NIR-light driven selective photoreduction CO2 to CH4
- 2022
-
In: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373. ; 319
-
Journal article (peer-reviewed)abstract
- The construction of interfacial engineered heterojunctions is an effective strategy to broaden the optical response and facilitate charge separation. Herein, a novel 0D/1D Ag2S/Sb2S3 heterojunction is prepared by in-situ growth of Ag2S quantum dots on Sb2S3 nanorods using a simple hydrothermal approach. The 10% Ag2S/Sb2S3 (10AS) heterojunction exhibited efficient CO2 photoreduction activity with a CH4 yield of 6.75 µmol g−1 h−1, which is six times higher than that of pure Sb2S3 NTs. The CH4 selectivity of the 10AS heterojunction reach 96.1%, owing to the construction of dual-metal sites. Intriguingly, the composite photocatalyst could be extended to infrared light, leading to the full utilization of the incident light. In the 10AS heterojunction, the formation of Ag-S-Sb type covalent bonds is demonstrated by Raman and XAFS tests. The pathways of CO2 conversion to CH4 are discussed in detail. Therefore, the work provides a promising strategy for highly selective and efficient CO2 photoreduction.
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| 14. |
- Zhu, Lingxiao, et al.
(author)
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A NoC-Based Spatial DNN Inference Accelerator With Memory-Friendly Dataflow
- 2023
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In: IEEE design & test. - : Institute of Electrical and Electronics Engineers (IEEE). - 2168-2356 .- 2168-2364. ; 40:6, s. 39-50
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Journal article (peer-reviewed)abstract
- This article addresses the challenges of excessive storage overhead and the absence of sparsity-aware design in Network-on-Chip (NoC)-based spatial deep neural network accelerators. The authors present a prototype chip that outperforms existing accelerators in both energy and area efficiency, demonstrated on TSMC 28-nm process technology. —Mahdi Nikdast, Colorado State University, USA —Miquel Moreto, Barcelona Supercomputing Center, Spain —Masoumeh (Azin) Ebrahimi, KTH Royal Institute of Technology, Sweden —Sujay Deb, IIIT Delhi, India
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| 15. |
- Abbasi, Rasha, et al.
(author)
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IceCube search for neutrinos from GRB 221009A
- 2023
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In: Proceedings of 38th International Cosmic Ray Conference (ICRC 2023). - : Sissa Medialab Srl.
-
Conference paper (peer-reviewed)abstract
- GRB 221009A is the brightest Gamma Ray Burst (GRB) ever observed. The observed extremelyhigh flux of high and very-high-energy photons provide a unique opportunity to probe the predictedneutrino counterpart to the electromagnetic emission. We have used a variety of methods to searchfor neutrinos in coincidence with the GRB over several time windows during the precursor, promptand afterglow phases of the GRB. MeV scale neutrinos are studied using photo-multiplier ratescalers which are normally used to search for galactic core-collapse supernovae neutrinos. GeVneutrinos are searched starting with DeepCore triggers. These events don’t have directionallocalization, but instead can indicate an excess in the rate of events. 10 GeV - 1 TeV and >TeVneutrinos are searched using traditional neutrino point source methods which take into accountthe direction and time of events with DeepCore and the entire IceCube detector respectively. The>TeV results include both a fast-response analysis conducted by IceCube in real-time with timewindows of T0 − 1 to T0 + 2 hours and T0 ± 1 day around the time of GRB 221009A, as well asan offline analysis with 3 new time windows up to a time window of T0 − 1 to T0 + 14 days, thelongest time period we consider. The combination of observations by IceCube covers 9 ordersof magnitude in neutrino energy, from MeV to PeV, placing upper limits across the range forpredicted neutrino emission.
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| 16. |
- Chen, Hongxia, et al.
(author)
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PRL2 Phosphatase Promotes Oncogenic KIT Signaling in Leukemia Cells through Modulating CBL Phosphorylation
- 2024
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In: Molecular Cancer Research. - 1541-7786. ; 22:1, s. 94-103
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Journal article (peer-reviewed)abstract
- Receptor tyrosine kinase KIT is frequently activated in acute myeloid leukemia (AML). While high PRL2 (PTP4A2) expression is correlated with activation of SCF/KIT signaling in AML, the underlying mechanisms are not fully understood. We discovered that inhibition of PRL2 significantly reduces the burden of oncogenic KIT-driven leukemia and extends leukemic mice survival. PRL2 enhances oncogenic KIT signaling in leukemia cells, promoting their proliferation and survival. We found that PRL2 dephosphorylates CBL at tyrosine 371 and inhibits its activity toward KIT, leading to decreased KIT ubiquitination and enhanced AKT and ERK signaling in leukemia cells.
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| 17. |
- Li, Wenjie, et al.
(author)
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Electrochemical removal of NOx by La0.8Sr0.2Mn1−xNixO3 electrodes in solid electrolyte cells : Role of Ni substitution
- 2021
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In: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894. ; 420
-
Journal article (peer-reviewed)abstract
- Electrochemical removal of nitrogen oxides (NOx) by solid electrolyte cells (SECs) is a promising technology due to no required reductant. Herein, a series of La0.8Sr0.2Mn1−xNixO3 (0 ≤ x ≤ 0.5) perovskites were first synthesized and utilized as the electrode materials of SECs. The role of Ni substitution in electrode performance and NOx reduction mechanism were revealed by various experimental characterization and first-principle calculations. The results indicate that the moderate Ni substitution (x ≤ 0.3) increased the NOx conversion of electrodes while reduced the polarization resistance. The further investigation shows that this improvement was attributed to the more surface oxygen vacancies, better reducibility and higher Mn4+ proportion of the Ni-substituted perovskites. The electrochemical impedance spectroscopy (EIS) shows that these changes facilitated the NOx adsorption and dissociation processes on the electrode. According to first-principle calculations, the Ni-substituted perovskite had a lower formation energy of surface oxygen vacancy, while the NO molecule adsorbed on defect surface gained more electrons thus was easier to be reduced and dissociated. Finally, the electrode performance at different operating temperatures and the operational stability were verified.
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| 18. |
- Li, Wenjie, et al.
(author)
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La0.75Sr0.25Cr0.5Mn0.5O3-δ-Ce0.8Sm0.2O1.9 as composite electrodes in symmetric solid electrolyte cells for electrochemical removal of nitric oxide
- 2020
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In: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373. ; 264
-
Journal article (peer-reviewed)abstract
- Symmetric solid electrolyte cells with La0.75Sr0.25Cr0.5Mn0.5O3-δ (LSCM)-Ce0.8Sm0.2O1.9 (SDC) composite electrodes are employed for nitric oxide (NO) removal. The LSCM powders are synthesized and the cells with LSCM-SDC composite electrodes are fabricated successfully. The results show that moderate SDC addition in LSCM electrode improves the cell performance due to the expansion of three phase boundaries (TPBs). The electrode with 30 wt% SDC has the highest NO conversion of 69.2% and the lowest polarization resistance at 750 °C in 1000 ppm NO. The cathodic polarization activates the cathode because of the Cr/Mn ions reduction, more surface oxygen vacancies and Cr metal exsolution. The cell has good tolerances for H2O, CO2, and SO2, but excess O2 competes with NO for TPBs seriously. The sufficient stability and flexible operation mode of the cell are also proved. Finally, the NO adsorption mechanism on LSCM surface is revealed by density functional theory (DFT) calculations.
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| 19. |
- Li, Zhiyang, et al.
(author)
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Magnetic carbon nanotube modified S-scheme TiO2-x/g-C3N4/CNFe heterojunction coupled with peroxymonosulfate for effective visible-light-driven photodegradation via enhanced interfacial charge separation
- 2023
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In: Separation and Purification Technology. - : Elsevier. - 1383-5866 .- 1873-3794. ; 308
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Journal article (peer-reviewed)abstract
- To remediate water bodies contaminated with organic micropollutants, recyclable and visible-light-driven coupled photocatalysis-peroxymonosulfate (PMS) activation systems were established by synthesizing magnetic-carbon-nanotubes (CNFe) modified TiO2-x/g-C3N4/CNFe (TCNCNFe) S-scheme heterojunction with oxygen vacancies (O-v) by a simple hydrothermal-calcination approach. The introduction of O-v and CNFe enhances the visible-light-harvesting efficiency and the internal electric field across the heterojunction accompanying favorable energy band bending could effectively migrate the photoexcited electrons along the S-scheme mechanism, thus highly suppressing in situ recombination and improving charge separation. Therefore the TCNCNFe-(30-500)/PMS/Vis system achieved 95.4% removal efficiency of atrazine after 30 min irradiation, meanwhile exhibited excellent recyclability without metal ion leaching due to the unique pod-like nanostructure of CNFe. Moreover, the impacts of certain various reaction variables on pollutant removal were explored to evaluate the practical application potential. Interestingly, the biotoxicity of the treated reaction filtrate was significantly alleviated compared to that of ATZ solution. Furthermore, the exploration of photocatalytic reaction mechanism revealed that the dominant reactive oxidizing species contributed in the following order: h(+) > (OH)-O-center dot > O-center dot(2)- > (SO4-)-S-center dot, and the feasible photodegradation pathway of atrazine was presented based on the determined in-termediates. Hence, this research work holds great promise in ecological environment protection using sustainable solar energy.
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| 20. |
- Sun, Xiao, et al.
(author)
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Gradient-Reduced Graphene Oxide Aerogel with Ultrabroadband Absorption from Microwave to Terahertz Bands
- 2023
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In: ACS Applied Nano Materials. - : AMER CHEMICAL SOC. - 2574-0970.
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Journal article (peer-reviewed)abstract
- Ultrabroadband electromagnetic (EM) absorbers, especially those covering microwave to terahertz (THz) bands, are urgently desired in multispectral applications such as 6G communication, radar stealth, atmospheric remote sensing, and radio astronomy. Here, we demonstrate that chemically reduced graphene oxide aerogels can be designed as an excellent absorber with the features of ultrabroadband, light weight, compressibility, and high-temperature resistance. This magnetic-free pyramidal absorber shows remarkably broad qualified absorption bandwidth from 4.7 GHz to 4 THz, with reflection loss < -20 dB in the microwave and < -40 dB in the THz band. Especially, an unprecedentedly excellent average absorption intensity of -53.9 dB (absorptivity over 99.999%) is obtained in the frequency range from 0.5 to 4 THz. We experimentally clarify that the gradient macrostructure together with the porous microstructure underlies the continuous impedance matching in such a large frequency range spanning about 3 orders of magnitude and leads to the consecutive strong EM absorption from microwave to terahertz. We believe that this absorber will offer multifunctional and multispectral applications in many scientific and technological fields.
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| 21. |
- Wei, Ting, et al.
(author)
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Developed and developing world responsibilities for historical climate change and CO2 mitigation
- 2012
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In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 109:32, s. 12911-12915
-
Journal article (peer-reviewed)abstract
- At the United Nations Framework Convention on Climate Change Conference in Cancun, in November 2010, the Heads of State reached an agreement on the aim of limiting the global temperature rise to 2 degrees C relative to preindustrial levels. They recognized that long-term future warming is primarily constrained by cumulative anthropogenic greenhouse gas emissions, that deep cuts in global emissions are required, and that action based on equity must be taken to meet this objective. However, negotiations on emission reduction among countries are increasingly fraught with difficulty, partly because of arguments about the responsibility for the ongoing temperature rise. Simulations with two earth-system models (NCAR/CESM and BNU-ESM) demonstrate that developed countries had contributed about 60-80%, developing countries about 20-40%, to the global temperature rise, upper ocean warming, and sea-ice reduction by 2005. Enacting pledges made at Cancun with continuation to 2100 leads to a reduction in global temperature rise relative to business as usual with a 1/3-2/3 (CESM 33-67%, BNU-ESM 35-65%) contribution from developed and developing countries, respectively. To prevent a temperature rise by 2 degrees C or more in 2100, it is necessary to fill the gap with more ambitious mitigation efforts.
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| 22. |
- Yan, Ruijuan, et al.
(author)
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Effects of Doping Ni on the Microstructures and Thermoelectric Properties of Co-Excessive NbCoSn Half-Heusler Compounds
- 2021
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In: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 13:29, s. 34533-34542
-
Journal article (peer-reviewed)abstract
- The half-Heusler (HH) compound NbCoSn with 18 valence electrons is a promising thermoelectric (TE) material due to its appropriate electrical properties as well as its suitable thermal and chemical stability. Nowadays, doping/substitution and tailoring of microstructures are common experimental approaches to enhance the TE performance of HH compounds. However, detailed theoretical insights into the effects of doping on the microstructures and TE properties are still missing. In this work, the microstructure of NbCoSn was tailored through precipitating the full-Heusler phases in the matrix by changing the nominal ratio of Co and Ni on the Co sites, focusing on the resulting TE properties. Further, first-principles calculations were employed to understand the relationship between the microstructure and the TE properties from the thermodynamic point of view. Detailed analysis of the electronic structure reveals that the presence of excess Co/Ni contributes to the increasing carrier concentration. Through an increase in the electrical conductivity and a reduction in the thermal conductivity, the TE performance is improved. Therefore, the present work offers a new pathway and insights to enhance the TE properties by modifying the microstructure of HH compounds via tailoring the chemical compositions.
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| 23. |
- Yang, Fangkai, et al.
(author)
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Diffusion-Based Time Series Data Imputation for Cloud Failure Prediction at Microsoft 365
- 2023
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In: ESEC/FSE 2023 - Proceedings of the 31st ACM Joint Meeting European Software Engineering Conference and Symposium on the Foundations of Software Engineering. - : Association for Computing Machinery (ACM). ; , s. 2050-2055
-
Conference paper (peer-reviewed)abstract
- Ensuring reliability in large-scale cloud systems like Microsoft 365 is crucial. Cloud failures, such as disk and node failure, threaten service reliability, causing service interruptions and financial loss. Existing works focus on failure prediction and proactively taking action before failures happen. However, they suffer from poor data quality, like data missing in model training and prediction, which limits performance. In this paper, we focus on enhancing data quality through data imputation by the proposed Diffusion+, a sample-efficient diffusion model, to impute the missing data efficiently conditioned on the observed data. Experiments with industrial datasets and application practice show that our model contributes to improving the performance of downstream failure prediction.
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| 24. |
- Yuan, Wenping, et al.
(author)
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Differentiating moss from higher plants is critical in studying the carbon cycle of the boreal biome.
- 2014
-
In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 5
-
Journal article (peer-reviewed)abstract
- The satellite-derived normalized difference vegetation index (NDVI), which is used for estimating gross primary production (GPP), often includes contributions from both mosses and vascular plants in boreal ecosystems. For the same NDVI, moss can generate only about one-third of the GPP that vascular plants can because of its much lower photosynthetic capacity. Here, based on eddy covariance measurements, we show that the difference in photosynthetic capacity between these two plant functional types has never been explicitly included when estimating regional GPP in the boreal region, resulting in a substantial overestimation. The magnitude of this overestimation could have important implications regarding a change from a current carbon sink to a carbon source in the boreal region. Moss abundance, associated with ecosystem disturbances, needs to be mapped and incorporated into GPP estimates in order to adequately assess the role of the boreal region in the global carbon cycle.
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| 25. |
- Zhan, Liangtong, et al.
(author)
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Effects of multiscale heterogeneity on transport in three-dimensional fractured porous rock with a rough-walled fracture network
- 2022
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In: Computers and geotechnics. - : Elsevier BV. - 0266-352X .- 1873-7633. ; 148, s. 104836-
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Journal article (peer-reviewed)abstract
- This study numerically analyzed the effect of multiscale heterogeneity on flow and transport response of a threedimensional (3D) fractured porous rock with rough-walled fracture network. 3D discrete fracture matrix (DFM) models with different heterogeneity scales (network-scale, fracture-to-fracture-scale, and individual fracture scale) were generated. The results showed that the velocity and concentration distributions among the different DFMs were highly variable due to multiscale heterogeneity. The cumulative distribution function curves (CDFs) of the concentration disctribution indicated that fracture-to-fracture-scale heterogeneity led to an earlier breakthrough time than network-scale heterogeneity, and this behavior was further enhanced by individual fracture-scale heterogeneity, suggesting that transport was accelerated by enhanced local channeling flow with increasing fracture roughness. The complementary cumulative distribution function curves (CCDFs) showed obvious long tailing as heterogeneity increased from fracture-to-fracture-scale to individual fracture-scale. Compared with the case where only network-scale heterogeneity was considered, the calculated downstream concentration with fracture-to-fracture-scale heterogeneity increased first from 0.670 to 0.709. However, the downstream concentration then decreased from 0.684 to 0.618 as the roughness increased from & USigma; = 0.03 mm to & USigma; = 0.07 mm. These results can help predict the migration behavior of radioactive nuclides in far-field areas and assess the long-term performance of deep geological repositories.
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| 26. |
- Zhang, Zhenzong, et al.
(author)
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Internal electric field engineering step-scheme–based heterojunction using lead-free Cs3Bi2Br9 perovskite–modified In4SnS8 for selective photocatalytic CO2 reduction to CO
- 2022
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In: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373. ; 313
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Journal article (peer-reviewed)abstract
- This study focuses on improving photocatalytic CO2 reduction reaction (CRR) activity and modulating product selectivity. An In4SnS8/Cs3Bi2Br9-X (ISS/CBB-X) heterojunction is prepared using novel lead-free Cs3Bi2Br9 perovskite quantum dot–modified In4SnS8, which shows considerable potential as photocatalysts for CRRs under visible light. The optimised ISS/CBB photocatalyst exhibits high activity and CO selectivity with a CO yield and selectivity of 9.55 μmol g−1 h−1 and 92.9%, respectively, 3.8 and 1.5 times higher than those of pristine ISS, respectively. Moreover, the step-scheme (S-scheme) mechanism can be fully confirmed via in situ irradiated X-ray photoelectron spectroscopy, in situ electron spin resonance, femtosecond time-resolved absorption spectroscopy and density functional theory calculations. Based on in situ diffuse reflectance spectra and theoretical investigations, the ISS/CBB shows a decreased energy barrier towards CO2 reduction to CO through an adsorbed ⁕COOH intermediate. This study contributes to the further understanding of fabricating efficient S-scheme-based photocatalysts for selective CRR.
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