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(Fe4Cr4Ni)9C4 is a metal carbide mineral formed by combination of Fe, Cr and Ni with C. It occurs in a chromite deposit in the Luobusha ophiolite, Tibet. Based on the determination of its crystal structure, the empirical formula is (Fe4.12Cr3.84Ni0.96)8.92C3.70 and the simplified formula is (Fe4Cr4Ni)4C9. The mineral is hexagonal with a = 1.38392(2) nm, c = 0.44690(9) nm, pace group P63 m c, Z=6 and the calculated specific gravity Dx = 7.089 g/cm3. Fe, Cr and Ni occupy different crystallographic sites and their coordination numbers are approximately 12, forming an alternate stacking sequence of flat and puckered layers along the c axis. Some metallic atoms have a defect structure. The interatomic distances of Fe, Cr and Ni are 0.2525-0.2666 nm, and the distances between Fe, Cr, Ni and C are 0.1893-0.2169 nm. The coordination number of carbon is 6. It occurs in interstices of the metallic atoms Fe, Cr and Ni to form trigonalprismatically coordinated polyhedra. These coordination polyhedra are linked with each other via shared corners or shared edges into a new type of metal carbide structure.

The detection of samples at ultralow concentrations (one to ten copies in 100 μl) in biofluids is hampered by the orders-of-magnitude higher amounts of ‘background’ biomolecules. Here we report a molecular system, immobilized on a liquid-gated graphene field-effect transistor and consisting of an aptamer probe bound to a flexible single-stranded DNA cantilever linked to a self-assembled stiff tetrahedral double-stranded DNA structure, for the rapid and ultrasensitive electromechanical detection (down to one to two copies in 100 μl) of unamplified nucleic acids in biofluids, and also of ions, small molecules and proteins, as we show for Hg 2+ , adenosine 5′-triphosphate and thrombin. We implemented an electromechanical biosensor for the detection of SARS-CoV-2 into an integrated and portable prototype device, and show that it detected SARS-CoV-2 RNA in less than four minutes in all nasopharyngeal samples from 33 patients with COVID-19 (with cycle threshold values of 24.9–41.3) and in none of the 54 COVID-19-negative controls, without the need for RNA extraction or nucleic acid amplification. A self-assembled DNA-based system immobilized on a liquid-gated graphene field-effect transistor can electromechanically detect ultralow levels of unamplified ions, nucleic acids, small molecules and proteins in biofluids.

Cotton fibers are initiated from the epidermal cells of the ovule before or on the day of anthesis. Gossypium arboreum SMA-4 mutant contains recessive mutation (sma-4(ha)) and has the phenotypes of fibreless seeds and glabrous stems. In this study, fine mapping and alternative splicing analysis indicated a nucleotide substitution (AG → AC) at splicing site in a homeodomain-leucine zipper IV family gene (GaHD1) might cause gene A3S (Alternative 3′ splicing) mistake, suggested that GaHD1 was the candidate gene of sma-4(ha). Many genes related to the fiber initiation are identified to be differentially expressed in the mutant which could result in the blocked fiber initiation signals such as H2O2, or Ca in the mutant. Further comparative physiological analysis of H2O2 production and Ca2+ flux in the SMA-4 and wide type cotton confirmed that H2O2 and Ca were important fiber initiation signals and regulated by GaHD1. The in vitro ovule culture of the mutant with hormones recovered the fibered phenotype coupled with the restoration of these signals. Overexpressing of GaHD1 in Arabidopsis increased trichome densities on the sepal, leaf, and stem tissues while transient silencing of the GaHD1 gene in G. arboreum reduced the trichome densities. These phenotypes indicated that GaHD1 is the candidate gene of SMA-4 with a crucial role in acting upstream molecular switch of signal transductions for cotton trichome and fiber initiations.

Phage therapy is recognized as a promising alternative to antibiotics in treating pulmonary bacterial infections, however, its use has not been reported for treating secondary bacterial infections during virus pandemics such as coronavirus disease 2019 (COVID-19). We enrolled 4 patients hospitalized with critical COVID-19 and pulmonary carbapenem-resistant Acinetobacter baumannii (CRAB) infections to compassionate phage therapy (at 2 successive doses of 10 9 plaque-forming unit phages). All patients in our COVID-19-specific intensive care unit (ICU) with CRAB positive in bronchoalveolar lavage fluid or sputum samples were eligible for study inclusion if antibiotic treatment failed to eradicate their CRAB infections. While phage susceptibility testing revealed an identical profile of CRAB strains from these patients, treatment with a pre-optimized 2-phage cocktail was associated with reduced CRAB burdens. Our results suggest the potential of phages on rapid responses to secondary CRAB outbreak in COVID-19 patients.

Over the past decade, the large-scale spread of influenza viruses has posed an increasing burden on public health. The effective screening of influenza agents requires a fast, precise, on-site and easy-to-operate method. Unfortunately, current screening methods face challenges in speed and accuracy, especially in complex on-site settings. Here, this work develops a nucleoprotein antibody-modified graphene field-effect transistor (NPAb-GFET) for rapid and highly precise detection of influenza A viruses. The functionalized monoclonal antibodies capture influenza virus nucleoprotein within 100 × 10−9 s on the sensing surface. Therefore, the developed NPAb-GFET achieves an average response time of 72.1 s when detecting influenza A viruses in clinical samples. Furthermore, the testing of 106 throat swab samples exhibits an accuracy of 99.1%. This finding provides a valuable diagnostic tool for the control of influenza viruses, accelerating the population-wide control of other epidemics.

We examined natural and anthropogenic controls on terrestrial evapotranspiration (ET) changes from 1982 to 2010 using multiple estimates from remote sensing-based datasets and process-oriented land surface models. A significant increasing trend of ET in each hemisphere was consistently revealed by observationally-constrained data and multi-model ensembles that considered historic natural and anthropogenic drivers. The climate impacts were simulated to determine the spatiotemporal variations in ET. Globally, rising CO2 ranked second in these models after the predominant climatic influences, and yielded decreasing trends in canopy transpiration and ET, especially for tropical forests and high-latitude shrub land. Increasing nitrogen deposition slightly amplified global ET via enhanced plant growth. Land-use-induced ET responses, albeit with substantial uncertainties across the factorial analysis, were minor globally, but pronounced locally, particularly over regions with intensive land-cover changes. Our study highlights the importance of employing multi-stream ET and ET-component estimates to quantify the strengthening anthropogenic fingerprint in the global hydrologic cycle.

This review summarizes recent advances in leveraging natural products from Chinese medicine to modulate the nuclear factor kappa B (NF-[kappa]B) signaling pathway for the prevention and treatment of neurodegenerative diseases (NDDs), focusing specifically on Alzheimer's disease (AD), Parkinson's disease (PD), and Amyotrophic lateral sclerosis (ALS). NF-[kappa]B proteins regulate cellular biological activity by binding to promoter regions in the nucleus and transcribing various protein-coding genes. Emerging evidence indicates that NF-[kappa]B plays a pivotal role in driving key hallmarks of NDD progression, including neuroinflammation, oxidative stress, mitochondrial dysfunction, and dysregulation of the cell cycle. Natural products from Chinese medicine exert modulatory effects on NF-[kappa]B signaling through diverse pharmacological mechanisms, ultimately improving cognitive and motor impairments in preclinical NDDs models. The pleiotropic nature of natural products derived from traditional Chinese medicine (TCM)--which operate through subunit-specific modulation of NF-[kappa]B--underscores their potential as next-generation therapeutics. Investigating the intricate regulation of NF-[kappa]B by natural products from Chinese medicine will not only enrich our understanding of the pathogenesis of NDDs but also establish a theoretical foundation for the development of new therapeutic drugs for NDDs, providing innovative strategies for prevention and treatment. Keywords: Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, neuroinflammation, oxidative stress

This review summarizes recent advances in leveraging natural products from Chinese medicine to modulate the nuclear factor kappa B (NF-κB) signaling pathway for the prevention and treatment of neurodegenerative diseases (NDDs), focusing specifically on Alzheimer's disease (AD), Parkinson's disease (PD), and Amyotrophic lateral sclerosis (ALS). NF-κB proteins regulate cellular biological activity by binding to promoter regions in the nucleus and transcribing various protein-coding genes. Emerging evidence indicates that NF-κB plays a pivotal role in driving key hallmarks of NDD progression, including neuroinflammation, oxidative stress, mitochondrial dysfunction, and dysregulation of the cell cycle. Natural products from Chinese medicine exert modulatory effects on NF-κB signaling through diverse pharmacological mechanisms, ultimately improving cognitive and motor impairments in preclinical NDDs models. The pleiotropic nature of natural products derived from traditional Chinese medicine (TCM)-which operate through subunit-specific modulation of NF-κB-underscores their potential as next-generation therapeutics. Investigating the intricate regulation of NF-κB by natural products from Chinese medicine will not only enrich our understanding of the pathogenesis of NDDs but also establish a theoretical foundation for the development of new therapeutic drugs for NDDs, providing innovative strategies for prevention and treatment.

Neutral water splitting is attractive for its use of non-corrosive and environmentally friendly electrolytes. However, catalyst development for hydrogen and oxygen evolution remains a challenge under neutral conditions. Here we report a simple electrodeposition and reductive annealing procedure to produce a highly active Ni-Co-Cr metal/metal oxide heterostructured catalyst directly on Ni foam. The resulting electrocatalyst for hydrogen evolution reaction (HER) requires only 198 mV of overpotential to reach 100 mA/cm 2 in 1 M potassium phosphate (pH = 7.4) and can operate for at least two days without significant performance decay. Scanning transmission electron microscopy coupled with electron energy loss spectroscopy (STEM-EELS) imaging reveals a Ni-Co alloy core decorated with blended oxides layers of NiO, CoO and Cr 2 O 3 . The metal/metal oxide interfaces are suggested to be responsible for the high HER activity.

Dynamic remodeling of the actin cytoskeleton plays a central role in the elongation of cotton fibers, which are the most important natural fibers in the global textile industry. Here, a high-resolution mapping approach combined with comparative sequencing and a transgenic method revealed that a G65V substitution in the cotton actin Gh_D04G0865 (GhACT17D in the wild-type) is responsible for the Gossypium hirsutum Ligon lintless-1 (Li1) mutant (GhACT17DM). In the mutant GhACT17DM from Li1 plant, Gly65 is substituted with valine on the lip of the nucleotide-binding domain of GhACT17D, which probably affects the polymerization of F-actin. Over-expression of GhACT17DM, but not GhACT17D, driven by either a CaMV35 promoter or a fiber-specific promoter in cotton produced a Li1-like phenotype. Compared with the wild-type control, actin filaments in Li1 fibers showed higher growth and shrinkage rates, decreased filament skewness and parallelness, and increased filament density. Taken together, our results indicate that the incorporation of GhACT17DM during actin polymerization disrupts the establishment and dynamics of the actin cytoskeleton, resulting in defective fiber elongation and the overall dwarf and twisted phenotype of the Li1 mutant.