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Ironmaking and steelmaking process research on Chinese long ring pommel Dao in Han dynasty
Kallikrein-8 mediates furin-independent Activin-A precursor processing to stimulate tumor growth in melanoma
Abstract Receptor binding of TGF-β and related ligands such as Activin-A requires cleavage of a furin site in their dimeric precursor proteins. Melanoma cells cleave one Activin-A subunit independently of furin and related proprotein convertases, raising questions of how this half-processed intermediate is generated and whether it influences tumor growth. Here, an siRNA library screen for proteases mediating this furin-independent “hemicleavage” identifies kallikrein (Klk)-8. While a KLK8 cleavage site in proActivin-A overlaps with the furin recognition sequence, its exposure is limited and requires prior transient acidification. Therefore, only furin efficiently converts proActivin-A to fully mature form both in tumor cells and in cell-free cleavage assays. Moreover, knockdown of Klk8 in syngeneic melanoma grafts suppresses Activin-A induced tumor growth, demonstrating that cleavage by only furin is not sufficient. Besides elucidating how Activin-A processing is regulated, our findings show that KLK8 holds promise as a target to mitigate Activin-A induced tumor growth.
Assessment of organophosphate pesticides in soils and vegetables from agricultural areas of Delta Central District, Nigeria
Liver fibrosis negatively impacts in vivo gene transfer to murine hepatocytes
Author Correction: Overburden movement law in strip filling mining of upward mining faces
Broadband microwave-rate dark pulse microcombs in dissipation-engineered LiNbO3 microresonators
Anticancer activity of Weizmannia coagulans MZY531on H22 tumor-bearing mice by regulating inflammation, autophagy-dependent apoptosis, and gut microbiota
Backscattering-free edge states below all bands in two-dimensional auxetic media
Abstract Unidirectional and backscattering-free propagation of sound waves is of fundamental interest in physics and highly sought-after in engineering. Current strategies utilize topologically protected chiral edge modes in bandgaps, or complex mechanisms involving active constituents or nonlinearity. Here we propose passive, linear, one-way edge states based on spin-momentum locking of Rayleigh waves in two-dimensional media in the limit of vanishing bulk to shear modulus ratio, which provides perfect unidirectional and backscattering-free edge propagation that is immune to any edge roughness and has no limitation on its frequency (instead of residing in gaps between bulk bands). We further show that such modes are characterized by a topological winding number that protects the linear momentum of the wave along the edge. These passive and backscattering-free edge waves have the potential to enable phononic devices in the form of lattices or continua that work in previously inaccessible frequency ranges.
Establishment and validation of a simple and accurate qPCR detection method for Haemophilus parasuis
Abstract As an infectious disease that poses a significant threat to the rapidly growing pig breeding industry, the detection of Haemophilus parasuis (HPS) is often compromised by various interfering substances present in the test sample during quantitative real-time PCR (qPCR). The rapid detection of HPS is important for the isolation of infectious pigs and their treatment. We designed and optimized a rapid qPCR test to detect the INFB gene of HPS in clinical and environmental samples on pig farms. The method was evaluated for its specificity, sensitivity, repeatability, anti-interference capability, and its ability to detect HPS in clinical samples. The results indicated that the method was specific for the detection of HPS when evaluated against pathogens and intestinal probiotics found in pig farms. By using a seven-fold dilution series of the recombinant plasmid DNA in triplicate, it was determined that the lowest limit of detection (LOD) for this method was less than 10 copies/µL. The results of inter-batch and intra-batch repeatability tests showed that the coefficient of variation (CV) was consistently below 1%. Furthermore, the impact of 14 endogenous and exogenous interfering substances on the Ct values detected by the HPS qPCR was found to be less than 5% when compared to the Ct values obtained in the absence of interfering substances. A total of 248 clinical samples were analyzed using the HPS qPCR, commercial kits, and corresponding national standards, yielding positive rates of 9.27%, 6.05%, and 9.27%, respectively. Notably, the positive and negative percent agreement between the detection method developed in this research and the national standard was 100%. These findings demonstrate that the established detection method is suitable for epidemiological research on HPS and for diagnosing clinical samples containing interfering substances, thereby providing essential technical support for the prevention and control of HPS.
Single-step laser-printed integrated sulfur cathode toward high-performance lithium–sulfur batteries
The m6A reader IGF2BP3 promotes HCC progression by enhancing MCM10 stability
Variation in wood density across South American tropical forests
Abstract Wood density is a critical control on tree biomass, so poor understanding of its spatial variation can lead to large and systematic errors in forest biomass estimates and carbon maps. The need to understand how and why wood density varies is especially critical in tropical America where forests have exceptional species diversity and spatial turnover in composition. As tree identity and forest composition are challenging to estimate remotely, ground surveys are essential to know the wood density of trees, whether measured directly or inferred from their identity. Here, we assemble an extensive dataset of variation in wood density across the most forested and tree-diverse continent, examine how it relates to spatial and environmental variables, and use these relationships to predict spatial variation in wood density over tropical and sub-tropical South America. Our analysis refines previously identified east-west Amazon gradients in wood density, improves them by revealing fine-scale variation, and extends predictions into Andean, dry, and Atlantic forests. The results halve biomass prediction errors compared to a naïve scenario with no knowledge of spatial variation in wood density. Our findings will help improve remote sensing-based estimates of aboveground biomass carbon stocks across tropical South America.
Prevalence of extrapulmonary tuberculosis and factors influencing successful treatment outcomes among notified cases in South India
Photoisomerization-mediated tunable pore size in metal organic frameworks for U(VI)/V(V) selective separation
Impact of temperature changes on the microstructure and mechanical characteristics of AISI 304 submerged in 5% HCl solution
Soft-matter-induced orderings in a solid-state van der Waals heterostructure
Abstract Deoxyribose nucleic acid (DNA), a type of soft matter, is often considered a promising building block to fabricate and investigate hybrid heterostructures with exotic functionalities. However, at this stage, investigations on DNA-enabled nanoelectronics have been largely limited to zero-dimensional (0D) and/or one-dimensional (1D) structures. Exploring their potential in higher dimensions, particularly in combination with hard matter solids such as van der Waals (vdW) two-dimensional (2D) materials, has proven challenging. Here, we show that 2D tessellations of DNA origami thin films, with a lateral size over 10 μm, can function as a sufficiently stiff substrate (Young’s modulus of ~4 GPa). We further demonstrate a two-dimensional soft-hard interface of matter (2D-SHIM), in which vdW layers are coupled to the 2D tessellations of DNA origami. In such 2D-SHIM, the DNA film can then serve as a superlattice due to its sub-100 nm sized pitch of the self-assemblies, which modulates the electronic states of the hybrid system. Our findings open up promising possibilities for manipulating the electronic properties in hard matter using soft matter as a super-structural tuning knob, which may find applications in next generation nanoelectronics.
Constraints of weathering intensity in different climate zones on coal accumulation environment
Abstract There are currently multiple hypotheses regarding coal accumulation models, each with certain limitations in applicability. This article investigates the relationship between modern sedimentation, soil and climate to analyze the distribution of coal across different geological periods, aiming to explain the coal accumulation environment within a unified theoretical framework. The research concludes that the intensity of weathering in various climate zones is a determining factor influencing coal formation, which also affects the distribution of two other climate-sensitive sedimentary deposits - evaporite and bauxite. These three types of sedimentary minerals can be considered as paleoclimatic indicators: cold and humid, warm and dry, and hot and humid. Furthermore, the impact of temperature on the mineralization of organic matter is significantly greater than that of redox conditions; in general, the mineralization of organic matter in high-temperature environments at mid-to-low latitudes exceeds productivity, resulting in low carbon sequestration rates. The conclusion drawn is that the optimal environment for peat or coal enrichment exists in a cold-humid climate zone characterized by low primary productivity, rather than in a tropical zone with high primary productivity. Additionally, the latitudinal shifts of cold temperate climate-controlled coal distribution, and the sediment types in these three climate zones sufficiently constrain coal-forming environments.
DNA lesions can frequently precede DNA:RNA hybrid accumulation
Abstract While DNA:RNA hybrids contribute to multiple genomic transactions, their unscheduled formation is a recognized source of DNA lesions. Here, through a suite of systematic screens, we rather observed that a wide range of yeast mutant situations primarily triggering DNA damage actually leads to hybrid accumulation. Focusing on Okazaki fragment processing, we establish that genic hybrids can actually form as a consequence of replication-born discontinuities such as unprocessed flaps or unligated Okazaki fragments. Strikingly, such “post-lesion” DNA:RNA hybrids neither detectably contribute to genetic instability, nor disturb gene expression, as opposed to “pre-lesion” hybrids formed upon defective mRNA biogenesis, e.g., in THO complex mutants. Post-lesion hybrids similarly arise in distinct genomic instability situations, triggered by pharmacological or genetic manipulation of DNA-dependent processes, both in yeast and human cells. Altogether, our data establish that the accumulation of transcription-born DNA:RNA hybrids can occur as a consequence of various types of natural or pathological DNA lesions, yet do not necessarily aggravate their genotoxicity.