Burkefogh3678

Use of high-resolution mass spectrometry (HRMS) including a MS calibration method has enabled simultaneous identification and quantification of knowns/unknowns. This has expanded our knowledge about the existing sample relevant chemical space in a way beyond reconciliation with a quantification task. This is largely due to fact that reference standards are not always available to achieve quantitative analysis. In this scenario, a semi-quantitative approach can fill the gap and provide a rough estimation of concentration. This research aimed to develop and compare several semi-quantification approaches based on chemical similarity or properties. The ionization efficiency scale was created for several groups of natural products. Advanced modeling approach based on a support vector machine was conducted to learn from the experimental ionization efficiency and apply it to unknowns or suspected compounds to predict their ionization efficiency in electrospray ionization mode. The developed semi-quantification workflows could be useful in most HRMS based "omics" areas, especially in natural products discovery.Methanol aqueous phase reforming (MAPR) reaction under mild conditions is one of the most practical ways to generate hydrogen (H2), in which the liquid vaporization unit could be removed by the water phase reforming, making the structure of an in situ H2 production reactor more compact. In this work, the H2 production performances of the metal-free catalyst, N-doped carbon dots/g-C3N4 (NCDs/g-C3N4; CN-x) composites, was investigated for the MAPR reaction under low temperature and normal pressure. The optimized metal-free catalyst (NCDs/g-C3N4; CN-0.7) displays a H2 yield of 19.5 μmol g-1 h-1 at 80 °C. More importantly, a clear understanding on the effective MAPR reaction at low temperature and normal pressure was acquired from in situ diffuse reflectance FTIR spectroscopy and the transient photovoltage test. The introduction of NCDs leads to the localization of surface charge, which is beneficial to the selective adsorption and polarization activation of polar molecules on the catalyst surface. This work provides a new strategy for the carbon-based catalyst design of the MAPR reaction at low temperatures.Cellulose nanocrystals (CNCs) have been widely studied as fillers to form reinforced nanocomposites with a wide range of applications, including the biomedical field. Here, we evaluated the possibility to combine them with fibrinogen and obtain fibrin hydrogels with improved mechanical stability as potential cellular scaffolds. In diluted conditions at a neutral pH, it was evidenced that fibrinogen could adsorb on CNCs in a two-step process, favoring their alignment under flow. Composite hydrogels could be prepared from concentrated fibrinogen solutions and nanocrystals in amounts up to 0.3 wt %. CNCs induced a significant modification of the initial fibrin fibrillogenesis and final fibrin network structure, and storage moduli of all nanocomposites were larger than those of pure fibrin hydrogels. Moreover, optimal conditions were found that promoted muscle cell differentiation and formation of long myotubes. These results provide original insights into the interactions of CNCs with proteins with key physiological functions and offer new perspectives for the design of injectable fibrin-based formulations.Cu12Sb4S13 has aroused great interest because of its earth-abundant constituents and intrinsic low thermal conductivity. However, the applications of Cu12Sb4S13 are hindered by its poor thermoelectric performance. Herein, it is shown that Gd substitution not only causes a significant increase in both electrical conductivity σ and thermopower S but also leads to dramatic drop in lattice thermal conductivity κL. Consequently, large ZT reaches 0.94 at 749 K for Cu11.7Gd0.3Sb4S13, which is ∼41% higher than the ZT value of undoped sample. Rietveld refinements of XRD results show that accompanying inhibition of impurity phase Cu3SbS4, the number of Cu vacancies increases substantially with substituted content x (x ≤ 0.3), which leads to reduced κL owing to intensive phonon scattering by the point defects and increased σ arising from the charged defects (VCu'). Crucially, synchrotron radiation photoelectron spectroscopy reveals substantial increment of electronic density of states at Fermi level upon Gd substitution, which is proven, by our first-principle calculations, to originate from contribution of Gd 4f orbit, resulting in enhancement of S. Our study provides us with a new path to enhance thermoelectric performance of Cu12Sb4S13.Microsized SiOx has been vigorously investigated as an advanced anode material for next-generation lithium-ion batteries. However, its practical application is seriously hampered by its huge volume variation during the repeated (de)lithiation process, which destroys the microparticle structure and results in rapid capacity fading. Herein, we propose the usage of trans-difluoroethylene carbonate (DFEC) as an electrolyte additive to maintain the structural integrity of microsized SiOx with a uniform carbon layer (SiOx@C). this website Compared with ethylene carbonate and fluoroethylene carbonate, DFEC has lower lowest unoccupied molecular orbital energy and higher reduction potential, which is easily reduced and promotes the in situ formation of a more stable LiF-rich solid electrolyte interphase (SEI) on the surface of anode materials. The LiF-rich SEI exhibits enhanced mechanical rigidity and ionic conductivity, thus enabling the microsized SiOx@C anodes' excellent lithium storage stability and high average Coulombic efficiency.Polyacrylamide-based hydrogels are widely used as potential candidates for cartilage replacement. However, their bioapplicability is sternly hampered due to their limited mechanical strength and puncture resistance. In the present work, the strength of polyacrylamide (PAM) hydrogels was increased using titanium oxide (TiO2) and carbon nanotubes (CNTs) separately and a combination of TiO2 with CNTs in a PAM matrix, which was interlinked by the bonding between nanoparticles and polymers with the deployment of density functional theory (DFT) approach. The synergistic effect and strong interfacial bonding of TiO2 and CNT nanoparticles with PAM are attributed to high compressive strength, elastic modulus (>0.43 and 2.340 MPa, respectively), and puncture resistance (estimated using the needle insertion test) for the PAM-TiO2-CNT hydrogel. The PAM-TiO2-CNT composite hydrogel revealed a significant self-healing phenomenon along with a sign toward the bioactivity and cytocompatibility by forming the apatite crystals in simulated body fluid as well as showing a cell viability of ∼99%, respectively. Furthermore, for new insights on interfacial bonding and structural and electronic features involved in the hydrogels, DFT was used. The PAM-TiO2-CNT composite model, constructed by two interfaces (PAM-TiO2 and PAM-CNT), was stabilized by H-bonding and van der Waals-type interactions. Employing the NCI plot, HOMO-LUMO gap, and natural population analysis tools, the PAM-TiO2-CNT composite has been found to be most stable. Therefore, the prepared polyacrylamide hydrogels in combination with the TiO2 and CNT can be a remarkable nanocomposite hydrogel for cartilage repair applications.Nitric oxide synthases (NOS) are the major sources of nitric oxide (NO), a small bioactive molecule involved in the regulation of many cellular processes. One of the most prominent functions of NO is regulation of vasodilatation and thereby control of blood pressure. Most important for vascular tone is NOS3. Endothelial NOS3-generated NO diffuses into the vascular smooth muscle cells, activates the soluble guanylate cyclase resulting in enhanced cGMP concentrations and smooth muscle cell relaxation. However, more and more evidence exist that also NOS1 and NOS2 contribute to vascular function. We summarize the current knowledge about the regulation of NOS expression in the vasculature by transcriptional, post-transcriptional and post-translational mechanisms, in regard to inflammation and innate immune pathways.Recently, Up-frameshift protein 1 (UPF1) is reported to be downregulated in various cancers and its low expression is closely correlated with poor prognosis. UPF1 is well known as a master regulator of nonsense-mediated mRNA decay (NMD), which serves as a highly conserved mRNA surveillance process protecting cells from aberrant toxic transcripts. Due to dysfunction of UPF1, NMD fails to proceed, which contributes to tumor initiation and progression. This review shows a brief summary of the aberrant expression, functional roles and molecular mechanisms of UPF1 during tumorigenesis. Increasing evidence has indicated that UPF1 could serve as a potential biomarker for cancer diagnosis and treatment for future clinical applications in cancer.In 2020, a novel strain of coronavirus (COVID-19) has led to a significant morbidity and mortality worldwide. As of the date of this writing, a total of 116 M cases has been diagnosed worldwide leading to 2.5 M deaths. The number of mortalities is directly correlated with the rise of innate immune cells (especially macrophages) in the lungs that secrete inflammatory cytokines (IL-1β and IL-6) leading to the development of "Cytokine Storm Syndrome" (CSS), multi-organ-failure and death. Given that currently the treatment of this condition is rare and release of effective vaccine might be months away, here, we review the plants and their pharmacologically active-compounds as potential phytopharmaceuticals for the virus induced inflammatory response. Experimental validation of the effectiveness of these natural compounds to prevent or reduce the cytokine storm might be beneficial as an adjunct treatment of SARS-CoV-2.Circular RNAs are single-stranded RNAs which are closed by covalent bonds during splicing. Different from other RNAs, circular RNAs are well known due to their circular structure. In recent years, many researches were conducted to investigate the role of circular RNAs in multiple diseases. To better understand the structure of circular RNAs, we reviewed the biogenesis and related regulation at first. Mechanisms by which circular RNAs exert effects were summarized then. Due to the conserved and brain-specific characteristic, circular RNAs in brain were depicted next. At last, considering the high mortality rate and disability rate caused by stroke globally, we reviewed related articles and summarized the results of original articles. Circular RNAs are suggested to be involved in the pathogenesis of stroke as well as some other neurological diseases which provides new insights and potential targets in clinical application.Being polymorphic, deoxyribonucleic acid is worthy of raise a variety of structure like right-handed B to left-handed Z conformation. In left-handed contour of DNA consecutive nucleotides substitute between syn-arrangement and anti-arrangement, through the chain. 2D gel electrophoresis comprising d(PCpG)n of topo isomers of a plasmid inserts d(pCpG)n, in this 'n' ranges among 8 to 21, indicate the change of B-Z DNA. The high denseness of salt is required for conversion of B configuration d(CG)n toward Z configuration. The rate of B to Z transition is measured by "Cytosine Analogues" and "Fluorescence Spectroscopy". h-ZαADAR1 that a Z-DNA's binding domain, binds and stabilizes one part in Z configuration and therefore the remaining half in B deoxyribonucleic acid configuration. At halfway point, it creates B-Z junction. "Stacking" is the main reason for the B-Z DNA junction construction. Upregulation of ADAM-12, related with Z-DNA is said to a cause for cancer, arthritis, and hypertrophy. Z-DNA forming sequence (ZFS) conjointly generates massive - scale deletion in cells from mammals.