Publications by authors named "Xuejie Gao"

9 Publications

  • Page 1 of 1

New Insights into the High-Performance Black Phosphorus Anode for Lithium-Ion Batteries.

Adv Mater 2021 Sep 22;33(35):e2101259. Epub 2021 Jul 22.

Department of Mechanical and Materials Engineering, University of Western Ontario, London, Ontario, N6A 5B9, Canada.

Black phosphorus (BP) is a promising anode material in lithium-ion batteries (LIBs) owing to its high electrical conductivity and capacity. However, the huge volume change of BP during cycling induces rapid capacity fading. In addition, the unclear electrochemical mechanism of BP hinders the development of rational designs and preparation of high-performance BP-based anodes. Here, a high-performance nanostructured BP-graphite-carbon nanotubes composite (BP/G/CNTs) synthesized using ball-milling method is reported. The BP/G/CNTs anode delivers a high initial capacity of 1375 mA h g at 0.15 A g and maintains 1031.7 mA h g after 450 cycles. Excellent high-rate performance is demonstrated with a capacity of 508.1 mA h g after 3000 cycles at 2 A g . Moreover, for the first time, direct evidence is provided experimentally to present the electrochemical mechanism of BP anodes with three-step lithiation and delithiation using ex situ X-ray diffraction (XRD), ex situ X-ray absorption spectroscopy (XAS), ex situ X-ray emission spectroscopy, operando XRD, and operando XAS, which reveal the formation of Li P , LiP, and Li P. Furthermore, the study indicates an open-circuit relaxation effect of the electrode with ex situ and operando XAS analyses.
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http://dx.doi.org/10.1002/adma.202101259DOI Listing
September 2021

A novel phosphoramide compound, DCZ0805, shows potent anti-myeloma activity via the NF-κB pathway.

Cancer Cell Int 2021 May 30;21(1):285. Epub 2021 May 30.

CAS Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai, 201203, China.

Background: Multiple myeloma (MM) is a highly aggressive and incurable clonal plasma cell disease with a high rate of recurrence. Thus, the development of new therapies is urgently needed. DCZ0805, a novel compound synthesized from osalmide and pterostilbene, has few observed side effects. In the current study, we intend to investigate the therapeutic effects of DCZ0805 in MM cells and elucidate the molecular mechanism underlying its anti-myeloma activity.

Methods: We used the Cell Counting Kit-8 assay, immunofluorescence staining, cell cycle assessment, apoptosis assay, western blot analysis, dual-luciferase reporter assay and a tumor xenograft mouse model to investigate the effect of DCZ0805 treatment both in vivo and in vitro.

Results: The results showed that DCZ0805 treatment arrested the cell at the G0/G1 phase and suppressed MM cells survival by inducing apoptosis via extrinsic and intrinsic pathways. DCZ0805 suppressed the NF-κB signaling pathway activation, which may have contributed to the inhibition of cell proliferation. DCZ0805 treatment remarkably reduced the tumor burden in the immunocompromised xenograft mouse model, with no obvious toxicity observed.

Conclusion: The findings of this study indicate that DCZ0805 can serve as a novel therapeutic agent for the treatment of MM.
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http://dx.doi.org/10.1186/s12935-021-01973-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8165811PMC
May 2021

mTORC1-Sch9 regulates hydrogen sulfide production through the transsulfuration pathway.

Aging (Albany NY) 2019 10 3;11(19):8418-8432. Epub 2019 Oct 3.

Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu 610064, Sichuan, China.

Endogenous hydrogen sulfide mediates anti-aging benefits of dietary restriction (DR). However, it is unclear how HS production is regulated by pathways related to DR. Due to the importance of mTORC1 pathway in DR, we investigated the effects of Sch9, a yeast homolog of mammalian S6K1 and a major substrate of mTORC1 on HS production in yeast . We found that inhibition of the mTORC1-Sch9 pathway by deletion, rapamycin or myriocin treatment resulted in a dramatic decrease in HS production. Although deficiency of did not alter the intracellular level of methionine, the intracellular level of cysteine increased in cells. The expression of and , two transsulfuration pathway genes encoding cystathionine gamma-lyase (CGL) and cystathionine beta-synthase (CBS), were also decreased under mTORC1-Sch9 inhibition. Overexpression of or in cells or WT cells treated with rapamycin rescued the deficiency of HS production. Finally, we also observed a reduction in HS production and lowering of both mRNA and protein levels of CGL and CBS in cultured human cells treated with rapamycin to reduce mTORC1 pathway activity. Thus, our findings reveal a probably conserved mechanism in which HS production by the transsulfuration pathway is regulated by mTORC1-Sch9 signaling.
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http://dx.doi.org/10.18632/aging.102327DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6814617PMC
October 2019

Promoting the Transformation of Li S to Li S: Significantly Increasing Utilization of Active Materials for High-Sulfur-Loading Li-S Batteries.

Adv Mater 2019 Jun 7;31(25):e1901220. Epub 2019 May 7.

Department of Mechanical and Materials Engineering, University of Western Ontario, London, Ontario, N6A 5B9, Canada.

Lithium-sulfur (Li-S) batteries with high sulfur loading are urgently required in order to take advantage of their high theoretical energy density. Ether-based Li-S batteries involve sophisticated multistep solid-liquid-solid-solid electrochemical reaction mechanisms. Recently, studies on Li-S batteries have widely focused on the initial solid (sulfur)-liquid (soluble polysulfide)-solid (Li S ) conversion reactions, which contribute to the first 50% of the theoretical capacity of the Li-S batteries. Nonetheless, the sluggish kinetics of the solid-solid conversion from solid-state intermediate product Li S to the final discharge product Li S (corresponding to the last 50% of the theoretical capacity) leads to the premature end of discharge, resulting in low discharge capacity output and low sulfur utilization. To tackle the aforementioned issue, a catalyst of amorphous cobalt sulfide (CoS ) is proposed to decrease the dissociation energy of Li S and propel the electrochemical transformation of Li S to Li S. The CoS catalyst plays a critical role in improving the sulfur utilization, especially in high-loading sulfur cathodes (3-10 mg cm ). Accordingly, the Li S/Li S ratio in the discharge products increased to 5.60/1 from 1/1.63 with CoS catalyst, resulting in a sulfur utilization increase of 20% (335 mAh g ) compared to the counterpart sulfur electrode without CoS .
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http://dx.doi.org/10.1002/adma.201901220DOI Listing
June 2019

Toward High Areal Energy and Power Density Electrode for Li-Ion Batteries via Optimized 3D Printing Approach.

ACS Appl Mater Interfaces 2018 Nov 8;10(46):39794-39801. Epub 2018 Nov 8.

Department of Mechanical and Materials Engineering , University of Western Ontario , London , Ontario N6A 5B9 , Canada.

High-energy and high-power-density lithium-ion batteries are promising energy storage systems for future portable electronics and electric vehicles. Here, three-dimensional (3D) patterned electrodes are created through the paste-extrusion-based 3D printing technique realizing a trade-off between high energy density and power density. The 3D electrodes possess several distinct merits over traditional flat thick electrodes, such as higher surface area, shorter ion transport path, and improved mechanical strength. Benefiting from these advantages, the 3D-printed thick electrodes present the higher specific capacity and improved cycling stability compared with those of the conventional thick electrodes. Upon comparison to the previous studies on 3D-printed electrodes, this study investigates the influence and optimization of 3D-printed LiFePO (LFP) electrodes with three different geometric shapes to achieve a high rate performance and long-term cycling stability. Accordingly, a series of 3D electrodes with different thickness were created, and an ultrathick (1500 μm) 3D-patterned electrode exhibits a high areal capacity of around 7.5 mA h cm, presenting remarkable value for state-of-the-art LFP cathodes. This work demonstrates patternable 3D printing as a potential strategy to fabricate thick electrodes toward high areal energy density and power density, which holds great promise for the future development of high-performance energy storage devices.
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http://dx.doi.org/10.1021/acsami.8b14797DOI Listing
November 2018

Effects of climate and potential policy changes on heating degree days in current heating areas of China.

Sci Rep 2018 07 5;8(1):10211. Epub 2018 Jul 5.

National Climate Center, China Meteorological Administration, Zhongguancun Nandajie 46, Haidian District, Beijing, 100081, China.

Based on climate simulations over East Asia from a high-resolution regional climate model under RCP4.5 and 8.5 scenarios, we examine the impact of future climate change and heating policy changes on energy demand in current central heating areas over China using the heating degree days (HDD) and the number of the heating days (NHD) with different base temperature as the indices. Based on current heating policy in China, significant decreases of NHDs are projected, with larger decreases under RCP8.5 than RCP4.5. This decrease of NHDs would cause a northward shift of the decadal heating boundary line, with significant implications for infrastructure planning and development. Changing the heating policy currently in practice to one used in Europe and USA would cause an immediate jump in NHDs and in HDDs; as warming progresses in the future, these effects attenuate with time in an approximately linear trend under the two scenarios. Under RCP8.5, by 2050, the effects of warming climate would dominate over the heating policy change, and heating demand would be lower than the present day HDD and continue to decrease until the end of the century. Energy demand and the number of the heating days during peak winter shows no dependence on heating policy, as the policy-induced increase of energy demand would occur primarily during warmer months of the year. In addition, the indices are further weighted by population, and results show that increases in both HDDs and NHDs can be found in parts of northern China due to the increased population there by the end of the 21st century.
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http://dx.doi.org/10.1038/s41598-018-28411-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6033895PMC
July 2018

Community-wide changes in intertaxonomic temporal co-occurrence resulting from phenological shifts.

Glob Chang Biol 2016 05 29;22(5):1746-54. Epub 2016 Feb 29.

Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 10029, China.

Global climate change is known to affect the assembly of ecological communities by altering species' spatial distribution patterns, but little is known about how climate change may affect community assembly by changing species' temporal co-occurrence patterns, which is highly likely given the widely observed phenological shifts associated with climate change. Here, we analyzed a 29-year phenological data set comprising community-level information on the timing and span of temporal occurrence in 11 seasonally occurring animal taxon groups from 329 local meteorological observatories across China. We show that widespread shifts in phenology have resulted in community-wide changes in the temporal overlap between taxa that are dominated by extensions, and that these changes are largely due to taxa's altered span of temporal occurrence rather than the degree of synchrony in phenological shifts. Importantly, our findings also suggest that climate change may have led to less phenological mismatch than generally presumed, and that the context under which to discuss the ecological consequences of phenological shifts should be expanded beyond asynchronous shifts.
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http://dx.doi.org/10.1111/gcb.13199DOI Listing
May 2016

Sch9 regulates intracellular protein ubiquitination by controlling stress responses.

Redox Biol 2015 Aug 9;5:290-300. Epub 2015 Jun 9.

Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China. Electronic address:

Protein ubiquitination and the subsequent degradation are important means by which aberrant proteins are removed from cells, a key requirement for long-term survival. In this study, we found that the overall level of ubiquitinated proteins dramatically decreased as yeast cell grew from log to stationary phase. Deletion of SCH9, a gene encoding a key protein kinase for longevity control, decreased the level of ubiquitinated proteins in log phase and this effect could be reversed by restoring Sch9 function. We demonstrate here that the decrease of ubiquitinated proteins in sch9Δ cells in log phase is not caused by changes in ubiquitin expression, proteasome activity, or autophagy, but by enhanced expression of stress response factors and a decreased level of oxidative stress. Our results revealed for the first time how Sch9 regulates the level of ubiquitinated proteins and provides new insight into how Sch9 controls longevity.
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http://dx.doi.org/10.1016/j.redox.2015.06.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4477112PMC
August 2015

Developed and developing world responsibilities for historical climate change and CO2 mitigation.

Proc Natl Acad Sci U S A 2012 Aug 23;109(32):12911-5. Epub 2012 Jul 23.

State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875/Zhuhai 519087, China.

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 °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 °C or more in 2100, it is necessary to fill the gap with more ambitious mitigation efforts.
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http://dx.doi.org/10.1073/pnas.1203282109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3420160PMC
August 2012
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