Magnetic ordering in the MAX phase (Cr0.96Mn0.04)(2)GeC is investigated by means of neutron powder diffraction (NPD). Upon cooling, the temperature dependence of the magnetization shows a two-step ...increase. The NPD refinement reveals that the first step, at 300 K, and the second step, at 38 K, originate from a collinear magnetic structure within the MAX phase and a spinel MnCr2O4 impurity phase, respectively. The former magnetic structure is oriented perpendicular to the c axis, with a net magnetic moment of similar to 0.6(2) mu(B) per Cr/Mn atom at 50 K. This is the first direct evidence for magnetic ordering within a bulk MAX phase. GRAPHICS IMPACT STATEMENT Direct neutron diffraction evidence for magnetic ordering in a bulk (Cr0.96Mn0.04)(2)GeC polycrystalline MAX phase sample is presented for the first time.
Recently, we presented a family of in-plane chemically ordered transition metal borides of the general formula (M′
2/3
M′′
1/3
)
2
AlB
2
. Here, we investigate incorporation of magnetic rare earth ...(RE) elements into this structure by synthesis and analysis of Mo
4/3
RE
2/3
AlB
2
, where RE = Ho, Tb, and Er. The crystal structure is verified by X-ray diffraction and scanning transmission electron microscopy, while the composition is derived from energy dispersive X-ray analysis. Through magnetization measurements, we also show that Mo
4/3
Ho
2/3
AlB
2
orders antiferromagnetically below 9 K. We suggest that (M′
2/3
M′′
1/3
)
2
AlB
2
could potentially be a versatile platform for new magnetic materials, in 3D as well as 2D.
This paper introduces magnetic elements to i-MAB phases family with a formula of Mo
4/3
RE
2/3
AlB
2
(RE = Ho, Er, and Tb), which opens a venue for further exploration of chemically ordered magnetic materials.
Pathological cardiac hypertrophy is a leading cause of morbidity and mortality in the world. However, it is still unclear the molecular mechanism revealing the progression of the disease. In the ...study, we illustrated that the expression of leukocyte immunoglobulin-like receptor B4 (LILRB4), associated with the pathological development of various inflammatory diseases, was down-regulated in pressure overload-induced hearts of patients and mice. LILRB4-knockout mice developed cardiac hypertrophy and heart failure by promoting cardiac dysfunction, fibrosis, inflammation and apoptosis. Mechanistically, transforming growth factor β1 (TGF-β1) expression was significantly promoted by LILRB4 deficiency in hearts of mice after aortic banding (AB) surgery. AB-induced inflammation in cardiac tissues was accelerated by LILRB4 deletion through elevating nuclear factor κB (NF-κB) signaling pathway. Furthermore, apoptosis triggered by AB operation in heart tissues was markedly enhanced in LILRB4-KO mice through promoting Caspase-3 activation. Importantly, the in vitro study indicated that LILRB4 knockdown-promoted fibrosis; inflammation and apoptosis were largely via the NF-κB signaling. Therefore, the findings above identified LILRB4 might be a negative regulator of cardiac remodeling, illustrating that LILRB4 represented as a therapeutic target for the prevention of cardiac hypertrophy and heart failure.
•LILRB4 knockout accelerates cardiac hypertrophy induced by aortic banding in mice.•LILRB4 deficiency promotes inflammation and apoptosis in aortic banding-stimulated heart injury.•Suppression of LILRB4 accelerates cardiac fibrosis, inflammation and apoptosis by activation of NF-κB (p65) signaling.
Here, we report the first asymmetric total synthesis of (+)-talassimidine and (+)-talassamine, two hetidine-type C
-diterpenoid alkaloids. A highly regio- and diastereoselective 1,3-dipolar ...cycloaddition of an azomethine ylide yielded a chiral tetracyclic intermediate in high enantiopurity, thus providing the structural basis for asymmetric assembly of the hexacyclic hetidine skeleton. In this key step, the introduction of a single chiral center induces four new continuous chiral centers. Another key transformation is the dearomative cyclopropanation of the benzene ring and subsequent S
2-like ring opening of the resultant cyclopropane ring with water as a nucleophile, which not only establishes the B ring but also precisely installs the difficult-to-achieve equatorial C7-OH group.
Abstract
Background
Acer yangbiense is a newly described critically endangered endemic maple tree confined to Yangbi County in Yunnan Province in Southwest China. It was included in a programme for ...rescuing the most threatened species in China, focusing on “plant species with extremely small populations (PSESP)”.
Findings
We generated 64, 94, and 110 Gb of raw DNA sequences and obtained a chromosome-level genome assembly of A. yangbiense through a combination of Pacific Biosciences Single-molecule Real-time, Illumina HiSeq X, and Hi-C mapping, respectively. The final genome assembly is ∼666 Mb, with 13 chromosomes covering ∼97% of the genome and scaffold N50 sizes of 45 Mb. Further, BUSCO analysis recovered 95.5% complete BUSCO genes. The total number of repetitive elements account for 68.0% of the A. yangbiense genome. Genome annotation generated 28,320 protein-coding genes, assisted by a combination of prediction and transcriptome sequencing. In addition, a nearly 1:1 orthology ratio of dot plots of longer syntenic blocks revealed a similar evolutionary history between A. yangbiense and grape, indicating that the genome has not undergone a whole-genome duplication event after the core eudicot common hexaploidization.
Conclusion
Here, we report a high-quality de novo genome assembly of A. yangbiense, the first genome for the genus Acer and the family Aceraceae. This will provide fundamental conservation genomics resources, as well as representing a new high-quality reference genome for the economically important Acer lineage and the wider order of Sapindales.
Here, we report the first asymmetric total synthesis of (+)-talassimidine and (+)-talassamine, two hetidine-type C20-diterpenoid alkaloids. A highly regio- and diastereoselective 1,3-dipolar ...cycloaddition of an azomethine ylide yielded a chiral tetracyclic intermediate in high enantiopurity, thus providing the structural basis for asymmetric assembly of the hexacyclic hetidine skeleton. In this key step, the introduction of a single chiral center induces four new continuous chiral centers. Another key transformation is the dearomative cyclopropanation of the benzene ring and subsequent SN2-like ring opening of the resultant cyclopropane ring with water as a nucleophile, which not only establishes the B ring but also precisely installs the difficult-to-achieve equatorial C7–OH group.
Background
Main challenges for COVID-19 include the lack of a rapid diagnostic test, a suitable tool to monitor and predict a patient’s clinical course and an efficient way for data sharing among ...multicenters. We thus developed a novel artificial intelligence system based on deep learning (DL) and federated learning (FL) for the diagnosis, monitoring, and prediction of a patient’s clinical course.
Methods
CT imaging derived from 6 different multicenter cohorts were used for stepwise diagnostic algorithm to diagnose COVID-19, with or without clinical data. Patients with more than 3 consecutive CT images were trained for the monitoring algorithm. FL has been applied for decentralized refinement of independently built DL models.
Results
A total of 1,552,988 CT slices from 4804 patients were used. The model can diagnose COVID-19 based on CT alone with the AUC being 0.98 (95% CI 0.97–0.99), and outperforms the radiologist’s assessment. We have also successfully tested the incorporation of the DL diagnostic model with the FL framework. Its auto-segmentation analyses co-related well with those by radiologists and achieved a high Dice’s coefficient of 0.77. It can produce a predictive curve of a patient’s clinical course if serial CT assessments are available.
Interpretation
The system has high consistency in diagnosing COVID-19 based on CT, with or without clinical data. Alternatively, it can be implemented on a FL platform, which would potentially encourage the data sharing in the future. It also can produce an objective predictive curve of a patient’s clinical course for visualization.
Key Points
•
CoviDet could diagnose COVID-19 based on chest CT with high consistency; this outperformed the radiologist’s assessment. Its auto-segmentation analyses co-related well with those by radiologists and could potentially monitor and predict a patient’s clinical course if serial CT assessments are available. It can be integrated into the federated learning framework.
•
CoviDet can be used as an adjunct to aid clinicians with the CT diagnosis of COVID-19 and can potentially be used for disease monitoring; federated learning can potentially open opportunities for global collaboration.
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