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Li, Lin

Publications and source records attributed to Li, Lin.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

A Subunit of ESCRT-III, MoIst1, Is Involved in Fungal Development, Pathogenicity, and Autophagy in Magnaporthe oryzae

The culprit of rice blast, Magnaporthe oryzae , is a filamentous fungus that seriously affects the yield and quality of rice worldwide. MoIst1, a subunit of ESCRT-III, is involved in identified ubiquitinated proteins and transports them into the intraluminal vesicles of multivesicular bodies (MVBs) for degradation in lysosomes. Here, we identify and characterize MoIst1 in M. oryzae . Disruption of MoIst1 leads to a significant decrease in sporulation and formation of appressoria, defects in response to oxidative stress, cell wall stress, hyperosmotic stress, and reduced pathogenicity. Deletion of MoIst1 also caused the decreased Pmk1 phosphorylation levels, appressorium formation, the delayed translocation and degradation of lipid droplets and glycogen, resulting in a decreased appressorium turgor. In addition, deletion of MoIst1 leads to an abnormal autophagy. In summary, our results indicate that MoIst1 is involved in sporulation, appressorium development, plant penetration, pathogenicity, and autophagy in M. oryzae .

Sun, Lixiao↗
DOE OSTI2022

Alpine permafrost could account for a quarter of thawed carbon based on Plio-Pleistocene paleoclimate analogue

Estimates of the permafrost-climate feedback vary in magnitude and sign, partly because permafrost carbon stability in warmer-than-present conditions is not well constrained. Here we use a Plio-Pleistocene lacustrine reconstruction of mean annual air temperature (MAAT) from the Tibetan Plateau, the largest alpine permafrost region on the Earth, to constrain past and future changes in permafrost carbon storage. Clumped isotope-temperatures (Δ 47 -T) indicate warmer MAAT (~1.2 °C) prior to 2.7 Ma, and support a permafrost-free environment on the northern Tibetan Plateau in a warmer-than-present climate. Δ 47 -T indicate ~8.1 °C cooling from 2.7 Ma, coincident with Northern Hemisphere glacial intensification. Combined with climate models and global permafrost distribution, these results indicate, under conditions similar to mid-Pliocene Warm period (3.3–3.0 Ma), ~60% of alpine permafrost containing ~85 petagrams of carbon may be vulnerable to thawing compared to ~20% of circumarctic permafrost. This estimate highlights ~25% of permafrost carbon and the permafrost-climate feedback could originate in alpine areas.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Circulating ACE2-expressing extracellular vesicles block broad strains of SARS-CoV-2

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the pandemic of the coronavirus induced disease 2019 (COVID-19) with evolving variants of concern. It remains urgent to identify novel approaches against broad strains of SARS-CoV-2, which infect host cells via the entry receptor angiotensin-converting enzyme 2 (ACE2). Herein, we report an increase in circulating extracellular vesicles (EVs) that express ACE2 (evACE2) in plasma of COVID-19 patients, which levels are associated with severe pathogenesis. Importantly, evACE2 isolated from human plasma or cells neutralizes SARS-CoV-2 infection by competing with cellular ACE2. Compared to vesicle-free recombinant human ACE2 (rhACE2), evACE2 shows a 135-fold higher potency in blocking the binding of the viral spike protein RBD, and a 60- to 80-fold higher efficacy in preventing infections by both pseudotyped and authentic SARS-CoV-2. Consistently, evACE2 protects the hACE2 transgenic mice from SARS-CoV-2-induced lung injury and mortality. Furthermore, evACE2 inhibits the infection of SARS-CoV-2 variants (α, β, and δ) with equal or higher potency than for the wildtype strain, supporting a broad-spectrum antiviral mechanism of evACE2 for therapeutic development to block the infection of existing and future coronaviruses that use the ACE2 receptor.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

On the thermal coarsening and transformation of nanoscale oxide inclusions in 316L stainless steel manufactured by laser powder bed fusion and its influence on impact toughness

The thermal evolution of nanoscale oxide inclusions in 316L stainless steel (SS) manufactured by laser powder bed fusion additive manufacturing (AM) was explored. The size, chemical composition, morphology, and distribution of the oxides were characterized as the function of heat treatment conditions. The study revealed the mechanistic driving force of the rapid oxide coarsening during recrystallization. Ostwald ripening governs oxide coarsening. The active grain boundary-oxide interaction at the early stage of recrystallization accelerated oxide coarsening via enhanced solute diffusion along grain boundaries. Pipe diffusion along dislocation cellular boundaries has a negligible contribution to oxide coarsening. At high temperatures (T> 1065 °C), although lattice diffusion primarily controlled the oxide growth, the contribution from the grain-boundary diffusion was necessary. The transformation from MnSiO 3 to CrMn 2 O 4 took place in the un-recrystallized grains but was not observed when recrystallization started. The interaction of grain boundary and oxides during recrystallization resulted in a high fraction of oxides accumulated at grain boundaries. While oxide coarsening does not significantly alter the toughness value, grain-boundary oxides promote microvoid formation and intergranular fracture under Charpy impact in the recrystallized AM 316L SS.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Evaluation of regional transport of PM2.5 during severe atmospheric pollution episodes in the western Yangtze River Delta, China

During winter 2018, the 16 prefecture-level cities in Anhui Province, Western Yangtze River Delta region, China had very high PM2.5 concentrations and prolonged pollution days. The impact of regional transport in the formation, accumulation, as well as dispersion of fine particulate matter (PM2.5) in Anhui Province was very significant. This study quantified and analyzed the vertical transport of PM2.5 in three major cities (Hefei, Fuyang, and Suzhou) of Anhui Province in January and July 2018 using the Weather Research and Forecasting (WRF) model coupled with the Community Multiscale Air Quality (CMAQ) model. The results of the inter-regional transport of PM2.5 revealed the dominant transport pathways for the three cities. The flux mainly flowed into Fuyang from Henan (2.23 and 1.42 kt/day in January and July, respectively) and Bozhou (1.96 and 1.21 kt/day in January and July, respectively), while the main flux from Fuyang flowed into Henan (-2.15 kt/day) and Lu'an (-1.91 kt/day) in January and Henan (-0.34 kt/day) and Bozhou (-0.29 kt/day) in July. In addition, the dominant transport pathways and the heights at which they occurred were identified: the northwest-southeast and northeast-south pathways in both winter and summer at both lower (?300 m) and higher (=300 m) levels for Fuyang; the northwest-south and northeast-southwest pathways in winter (at both lower and upper levels) and northwest-east and northeast-southwest pathways in summer at lower and upper levels for Hefei; and the northwest-southeast and northeast-south pathways in both winter (from 50 m up to the top level) and summer (between 100 and 300 m) for Suzhou. Furthermore, the intensities of daily PM2.5 transport fluxes in Fuyang during the atmospheric pollution episode (APE1) were stronger than the monthly average. These results show that joint emission controls across multiple cities along the identified pathways are urgently needed to reduce winter episodes.

Sulaymon, Ishaq D.↗
DOE OSTI2021

Apparatus for real-time size-distributed measurement of aerosol mass concentration

An impactor, system and method for performing real-time measurements of particles in aerosol gases. The impactor comprises a plurality of cascading stages having impaction plates, mass-measurement mechanisms retained on the impaction plates, and a nozzle plate. A signal line associated with each of the plurality of cascading stages is configured to relay signals from the mass-measurement mechanism of the associated stage to a computer-based system configured to receive the transmitted signals from the signal lines, and to correlate changes in the resonant frequencies to particle concentrations in real time.

Chen, Modi↗
DOE OSTI2021

Low-temperature and effective ex situ group V doping for efficient polycrystalline CdSeTe solar cells

CdTe solar cell technology is one of the lowest-cost methods of generating electricity in the solar industry, benefiting from fast CdTe absorber deposition, CdCl 2 treatment and Cu doping. However, Cu doping has low photovoltage and issues with instability. Doping group V elements into CdTe is therefore a promising route to address these challenges. Although high-temperature in situ group V doped CdSeTe devices have demonstrated efficiencies exceeding 20%, they face obstacles including post-deposition doping activation processes, short carrier lifetimes and low activation ratios. Here, we demonstrate low-temperature and effective ex situ group V doping for CdSeTe solar cells using group V chlorides. For AsCl 3 doped CdSeTe solar cells, the dopant activation ratio can be 5.88%, hole densities reach >2 × 10 15 cm -3 and carrier lifetime is longer than 20 ns. Thus, ex situ As doped CdSeTe solar cells show open-circuit voltages ~863 mV, compared to the highest open-circuit voltage of 852 mV for Cu doped CdSeTe solar cells.

14 SOLAR ENERGY↗
DOE OSTI2021

Prehydration of calcium sulfoaluminate (CSA) clinker at different relative humidities

The use of CSA cement in practice has been hindered by its unstable performance and short shelf-life caused by the prehydration of CSA clinker. In this study, the effect of ambient humidity on the prehydration rate and process of CSA clinker was investigated. The prehydration degree, ageing progress, and the dynamic change of mineral composition of CSA clinker exposed to five different relative humidities (ranging from 23% to 98%) for up to 180 days were studied. Experiments revealed that the ambient humidity of 60% RH can be considered a threshold value for storage of CSA clinker. Exposure of CSA clinker to RH higher than 60% will not only result in a significant decrease of hydraulic reactivity, but also in agglomeration of the clinker. Although the exposure of CSA clinker to RH lower than 60% has little effect on the hydraulic reactivity, the main hydration peak was found to be slightly delayed with the increase of RH.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Persistent high PM 2.5 pollution driven by unfavorable meteorological conditions during the COVID-19 lockdown period in the Beijing-Tianjin-Hebei region, China

Lockdown measures to curtail the COVID-19 pandemic in China halted most nonessential activities on January 23, 2020. Despite significant reductions in anthropogenic emissions, the Beijing-Tianjin-Hebei (BTH) region still experienced high air pollution concentrations. In this work, employing two emissions reduction scenarios, the Community Multiscale Air Quality (CMAQ) model was used to investigate the PM 2.5 concentrations change in this region. The model using the scenario (C3) with greater traffic reductions performed better compared to the observed PM 2.5 . Compared with the no reductions base-case (scenario C1), PM 2.5 reductions with scenario C3 were 2.70, 2.53, 2.90, 2.98, 3.30, 2.81, 2.82, 2.98, 2.68, and 2.83 µg/m 3 in Beijing, Tianjin, Shijiazhuang, Baoding, Cangzhou, Chengde, Handan, Hengshui, Tangshan, and Xingtai, respectively. During high-pollution days in scenario C3, the percentage reductions in PM 2.5 concentrations in Beijing, Tianjin, Shijiazhuang, Baoding, Cangzhou, Chengde, Handan, Hengshui, Tangshan, and Xingtai were 3.76, 3.54, 3.28, 3.22, 3.57, 3.56, 3.47, 6.10, 3.61, and 3.67%, respectively. However, significant increases caused by unfavorable meteorological conditions counteracted the emissions reduction effects resulting in high air pollution in BTH region during the lockdown period. This study shows that effective air pollution control strategies incorporating these results are urgently required in BTH to avoid severe pollution.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Combining glomerular basement membrane and tubular basement membrane assessment improves the prediction of diabetic end‐stage renal disease

Abstract Background To address the prognostic value of combining tubular basement membrane (TBM) and glomerular basement membrane (GBM) thickness in diabetic nephropathy (DN). Methods This retrospective study enrolled 110 patients with type 2 diabetes and biopsy‐proven DN from 2011 to 2018. The pathological findings were confirmed according to the Renal Pathology Society classifications. GBM and TBM thicknesses were determined using the Haas' direct measurement/arithmetic mean method and orthogonal intercept method, respectively. Cox proportional hazard models were used to investigate the hazard ratios (HRs) for the influence of combined GBM and TBM thickness for predicting end‐stage renal disease (ESRD). Results Patients were assigned to three groups according to the median GBM and TBM thickness: GBM lo TBM lo (GBM < 681 nm and TBM < 1200 nm), GBM hi TBM lo /GBM lo TBM hi (GBM ≥ 681 nm and TBM < 1200 nm, or GBM < 681 nm and TBM ≥ 1200 nm), and GBM hi TBM hi (GBM ≥ 681 nm and TBM ≥ 1200 nm). The GBM hi TBM lo /GBM lo TBM hi and GBM hi TBM hi groups displayed poorer renal function, a more severe glomerular classification and interstitial inflammation, and poorer renal survival rates than the GBM lo TBM lo group The GBM hi TBM lo /GBM lo TBM hi and GBM hi TBM hi groups had adjusted HRs of 1.49 (95% confidence interval [CI], 1.21‐9.75) and 3.07 (95% CI, 2.87‐12.78), respectively, compared with the GBM lo TBM lo group. Conclusions TBM thickness enhanced GBM thickness for renal prognosis in patients with type 2 diabetes.

Zhao, Lijun↗
DOE OSTI2020

Magnetic domain engineering in SrRuO3 thin films

Abstract Magnetic domain engineering in ferromagnetic thin films is a very important route toward the rational design of spintronics and memory devices. Although the magnetic domain formation has been extensively studied, artificial control of magnetic domain remains challenging. Here, we present the control of magnetic domain formation in paradigmatic SrRuO 3 /SrTiO 3 heterostructures via structural domain engineering. The formation of structural twin domains in SrRuO 3 films can be well controlled by breaking the SrTiO 3 substrate symmetry through engineering miscut direction. The combination of x-ray diffraction analysis of structural twin domains and magnetic imaging of reversal process demonstrates a one-to-one correspondence between structural domains and magnetic domains, which results in multi-step magnetization switching and anomalous Hall effect in films with twin domains. Our work sheds light on the control of the magnetic domain formation via structural domain engineering, which will pave a path toward desired properties and devices applications.

Materials Science↗
DOE OSTI2020

Multiscale modeling of shear banding in metallic glasses (Final report)

Metallic glasses (MGs) possess remarkably high strength but suffer from minimal tensile ductility due to the formation of catastrophic shear bands. The goal of this research project is to develop an understanding of the microstructures and deformation mechanisms that control shear banding in MGs, which will enable the development of MGs with enhanced plasticity. Two scientific objectives have been pursued. (1) Understand the underlying mechanisms of shear banding phenomena in presence of nanoscale heterogeneities in MGs. (2) Understand the evolution of MG heterogenous structure upon thermomechanical stimuli for plasticity enhancement through controlling and distributing multiple shear bands.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Application of Self-Interaction Corrected Density Functional Theory to Early, Middle, and Late Transition States

Density functional theory (DFT)-based methods often significantly underpredict chemical reaction barriers compared with experiments because of the tendency of DFT to over-stabilize transition states with stretched bonds due to the impact of unphysical electron self-interaction. But many reactions have early or late transition states where the transition state geometry closely resembles the reactants or products, respectively. The role of self-interaction in those cases is not known. Here we compare the performance of DFT with and without self-interaction correction (SIC) for describing the hydrogenation of CO and CO 2 catalyzed by a Lewis acid-base pair incorporated onto an aromatic cluster, using CCSD(T) results for reference. The three elementary steps in these reactions consist of an early, a middle, and a late transition. Our results show that the Perdew-Zunger SIC (PZ-SIC), implemented in the Fermi-L Lowdin orbital SIC (FLO-SIC) approach, qualitatively improves the description of the forward and reverse reaction barriers relative to uncorrected DFT for the middle transition, but not the early or late transitions. By contrast, the local scaling SIC (LSIC) method, also implemented in the FLO-SIC framework, significantly improves the calculated barriers over DFT and PZ-SIC in all but one case. Lastly, the results also show how the FLO-SIC approach can provide insight into the bonding in aromatic systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗