► Half-metallic ferromagnetism in quaternary Heusler alloys CoFeCrZ (Z=Al, Si, Ga, Ge). ► The influence of Coulomb interaction on the half-metallicity of CoFeCrZ. ► Half-metallicity is destroyed at ...the (001) surface of CoFeCrSi.
The high Curie temperatures and compatible lattice structure with conventional semiconductors for half-metallic Co2FeZ and Co2CrZ (Z=Al, Si, Ga, Ge) inspired us to design new quaternary Heusler half-metallic ferromagnets CoFeCrZ. Our first-principles calculations show that, within generalized gradient approximation for the electronic exchange–correlation functional, both CoFeCrGa and CoFeCrGe are nearly half-metals, while both CoFeCrAl and CoFeCrSi exhibit excellent half-metallic ferromagnetism with the large half-metallic gaps of 0.16 and 0.28eV, respectively. The half-metallicity of CoFeCrAl and CoFeCrSi is robust against the lattice compression (up to 7% and 4%, respectively). We also reveal that the half-metallicity is lost for both CoFeCrAl and CoFeCrGa but retentive for both CoFeCrSi and CoFeCrGe when the Coulomb interactions are considered. In addition, both CoFe- and CrSi-terminated (001) surfaces with and without antisite defects lose the bulk half-metallicity in CoFeCrSi.
In land plants the cuticle is the outermost layer interacting with the environment. This lipophilic layer comprises the polyester cutin embedded in cuticular wax; and it forms a physical barrier to ...protect plants from desiccation as well as from diverse biotic and abiotic stresses. However, the cuticle is not merely a passive, mechanical shield. The increasing research on plant leaves has addressed the active roles of the plant cuticle in both local and systemic resistance against a variety of plant pathogens. Moreover, the fruit cuticle also serves as an important determinant of fruit defense and quality. It shares features with those of vegetative organs, but also exhibits specific characteristics, the functions of which gain increasing attention in recent years. This review describes multiple roles of plant cuticle during plant-pathogen interactions and its responses to both leaf and fruit pathogens. These include the dynamic changes of plant cuticle during pathogen infection; the crosstalk of cuticle with plant cell wall and diverse hormone signaling pathways for plant disease resistance; and the major biochemical, molecular, and cellular mechanisms that underlie the roles of cuticle during plant-pathogen interactions. Although research developments in the field have greatly advanced our understanding of the roles of plant cuticle in plant defense, there still remain large gaps in our knowledge. Therefore, the challenges thus presented, and future directions of research also are discussed in this review.
We investigate the electronic structure and magnetic properties of the twelve quaternary Heusler alloys CoFeTiZ and CoFeVZ (Z=Al, Ga, Si, Ge, As, Sb) by using the first-principles calculations. It is ...shown that only CoFeTiSi, CoFeTiAs and CoFeVSb are half-metallic ferromagnets with considerable half-metallic gaps of 0.31, 0.18 and 0.17 eV, respectively. CoFeTiAl and CoFeTiGa are conventional semiconductors, and other alloys exhibit nearly half-metallicity or their half-metallic gaps are almost zero eV. We also find that the half-metallicities of CoFeTiSi, CoFeTiAs and CoFeVSb can be preserved under appropriate uniform and inplane strains. The considerable half-metallic gaps and the robust half-metallicities under uniform and inplane strains make CoFeTiSi, CoFeTiAs and CoFeVSb promising candidates for spintronic applications.
•The full displacement and strain fields are measured using DIC.•The history of dynamic stress intensity factor of rocks is determined.•The effect of loading rate on dynamic fracture properties is ...characterized.•Dependence of fracture propagation toughness on fracture velocity is obtained.
Loading rate is the main controlling factor in dynamic failure of rocks. In this paper, digital image correlation (DIC) combined with ultra-high speed photography is utilized to study the loading rate effect of a granitic rock – Laurentian granite using notched semi-circular bend (NSCB) method. The dynamic stress intensity factors and crack tip positions are determined from the displacement fields obtained using DIC. Fracture time, fracture toughness and crack growth velocity all exhibit loading rate dependence. The dependence of fracture propagation toughness on crack growth velocity is also obtained, which is in good agreement with that reported in the literature.
H5N1 avian influenza virus (AIV) has emerged as a pathogenic entity for a variety of species, including humans, in recent years. Here we report an outbreak among migratory birds on Lake Qinghaihu, ...China, in May and June 2005, in which more than a thousand birds were affected. Pancreatic necrosis and abnormal neurological symptoms were the major clinical features. Sequencing of the complete genomes of four H5N1 AIV strains revealed them to be reassortants related to a peregrine falcon isolate from Hong Kong and to have known highly pathogenic characteristics. Experimental animal infections reproduced typical highly pathogenic AIV infection symptoms and pathology.
Effective targeted therapy for non-small-cell lung cancer (NSCLC) patients with human epidermal growth factor receptor 2 (HER2) mutations remains an unmet need. This study investigated the antitumor ...effect of an irreversible pan-HER receptor tyrosine kinase inhibitor, pyrotinib.
Using patient-derived organoids and xenografts established from an HER2-A775_G776YVMA-inserted advanced lung adenocarcinoma patient sample, we investigated the antitumor activity of pyrotinib. Preliminary safety and efficacy of pyrotinib in 15 HER2-mutant NSCLC patients in a phase II clinical trial are also presented.
Pyrotinib showed significant growth inhibition of organoids relative to afatinib in vitro (P = 0.0038). In the PDX model, pyrotinib showed a superior antitumor effect than afatinib (P = 0.0471) and T-DM1 (P = 0.0138). Mice treated with pyrotinib displayed significant tumor burden reduction (mean tumor volume, −52.2%). In contrast, afatinib (25.4%) and T-DM1 (10.9%) showed no obvious reduction. Moreover, pyrotinib showed a robust ability to inhibit pHER2, pERK and pAkt. In the phase II cohort of 15 patients with HER2-mutant NSCLC, pyrotinib 400 mg resulted in a objective response rate of 53.3% and a median progression-free survival of 6.4 months.
Pyrotinib showed activity against NSCLC with HER2 exon 20 mutations in both patient-derived organoids and a PDX model. In the clinical trial, pyrotinib showed promising efficacy.
NCT02535507.
•Surface Canopy Water (SCW) affects radar backscatter, cross ratio and RVI.•SCW affects the relations between L-band observables and crop biophysical variables.•SCW has a confounding influence on VOD ...estimation.•Overpass time and daily patterns in SCW affect the retrieval of crop parameters.
The presence of surface water on the canopy affects radar backscatter. However, its influence on the relationship between radar backscatter and crop biophysical parameters has not been investigated. The aim of this study was to quantify the influence of surface canopy water (SCW) on the relationship between L-band radar backscatter and biophysical variables of interest in agricultural monitoring. In this study, we investigated the effect of SCW on the relationship between co- and cross-polarized radar backscatter, cross ratios (VH/VV and HV/HH), and radar vegetation index (RVI) and dry biomass, vegetation water content (VWC), plant height and leaf area index (LAI). In addition, the effect of SCW on estimated vegetation optical depth (VOD) and its relationship with internal VWC was investigated. The analysis was based on data collected during a field experiment in Florida, USA in 2018. A corn field was scanned with a truck-mounted, fully polarimetric, L-band radar along with continuous monitoring of SCW (dew, interception) and soil moisture every 15min for 58 days. In addition, pre-dawn destructive sampling was conducted to measure internal vegetation water content and dry biomass. Results showed that the presence of SCW can increase the radar backscatter up to 2 dB and this effect was lower for cross ratios (CRs) and RVI. The Spearman's rank correlations between radar observables and biophysical parameters were, on average, 0.2 higher for dry vegetation compared to wet vegetation. The estimated VOD from wet vegetation was generally higher than those from dry vegetation, which led to different fitting parameter (so-called b) values in the linear fit between VOD and VWC. The results presented here underscore the importance of considering the influence of SCW on the retrieval of biophysical variables of interest in agricultural monitoring. In particular, they highlight the importance of overpass time, and the impact that daily patterns in dew and interception can have on the retrieval of biophysical variables of interest.
To study the effectiveness of natural killer cell-derived exosome (NK-Exos)-entrapped paclitaxel (PTX-NK-Exos) in enhancing its anti-tumor effect.
The NK-Exos were isolated through ultra-high-speed ...centrifugation, and the PTX-NK-Exos system was constructed via electroporation. The morphology, particle size, Zeta potential and entrapment rate of PTX-NK-Exos were evaluated using transmission electron microscope (TEM), dynamic light scattering (DLS), Western blotting and high-performance liquid chromatography (HPLC), respectively. The uptake of Exos in human breast cancer MCF-7 cells was observed under a laser confocal microscope. Moreover, the effect of PTX-NK-Exos on MCF-7 cell viability was determined through methyl thiazolyl tetrazolium (MTT) assay, flow cytometry and 4',6-diamidino-2-phenylindole (DAPI) staining. The effects of PTX-NK-Exos on messenger ribonucleic acid (mRNA) and protein expressions of B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax) and Caspase-3 in MCF-7 cells were detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting, respectively.
The NK-Exos were successfully isolated via ultra-high-speed centrifugation, and they had uniform particle size and high expression of markers for Exos. MCF-7 cells could take up Exos. The PTX-NK-Exos drug delivery system was successfully prepared using electroporation. In PTX group and NK-Exos group, the proliferation of MCF-7 cells declined, the nuclear apoptosis was evident and the apoptosis rate of MCF-7 cells rose compared with those in Control group. In PTX group and PTX-NK-Exos group, the migration of MCF-7 cells declined compared with that in Control group. According to the results of qRT-PCR and Western blotting, PTX-NK-Exos exerted an anti-tumor effect through inducing the up-regulation of Bax and Caspase-3 in the apoptotic signaling pathway in tumor cells.
Exos isolated through ultra-high-speed centrifugation can be used to prepare the PTX-NK-Exos drug delivery system through electroporation. Drug-loaded Exos can effectively inhibit proliferation and induce apoptosis of tumor cells, thereby exerting an anti-tumor effect.
Highlights • Diabetes increases the lipid peroxidation of the hippocampus of rats. • Diabetes promotes the IKKβ/NF-κB activation and inflammatory level. • Diabetes impairs insulin signaling by ...suppressing PI3K/AKT activities. • Dietary fish oil prevents the alterations in diabetes and improves cognitive ability.
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