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Phytochemical profiling, antioxidant potential, and UHPLC-HRMS analysis of Phlomis genus aerial parts for therapeutic applications
A size-dependent ideal solution model for liquid–solid phase equilibria prediction in aqueous organic solutions
Predictive synthesis of aqueous organic solutions with desired liquid–solid phase equilibria could drive progress in industrial chemistry, cryopreservation, and beyond, but is limited by the predictive power of current solution thermodynamics models. In particular, few analytical models enable accurate liquidus and eutectic prediction based only on bulk thermodynamic properties of the pure components, requiring instead either direct measurement or costly simulation of solution properties. In this work, we demonstrate that a simple modification to the canonical ideal solution theory accounting for the entropic effects of dissimilar molecule sizes can transform its predictive power. Incorporating a Flory-style entropy of mixing term that includes both the mole and volume fractions of each component, we derive size-dependent equations for the ideal chemical potential and liquidus temperature, and use them to predict the binary phase diagrams of water and 10 organic solutes of varying sizes. We show that size-dependent prediction outperforms the ideal model in all cases, reducing average error in the predicted liquidus temperature by 59% (to 5.6 K), eutectic temperature by 45% (to 9.7 K), and eutectic composition by 43% (to 4.7 mol%), as compared to experimental data. Furthermore, by retaining the ideal assumption that the enthalpy of mixing is zero, we demonstrate that, for aqueous organic solutions, much of the deviation from ideality that is typically attributed to molecular interactions may in fact be explained by simple entropic size effects. These results suggest an underappreciated dominance of mixing entropy in these solutions, and provide a simple approach to predicting their phase equilibria.
RETRACTED ARTICLE: Insight into molecular and mutational scrutiny of epilepsy associated gene Gabrg2 leading to novel computer-aided drug designing
Weak individual preferences stabilize culture
Outcomes in the cultural arena are due to many factors but are there general rules that can suggest what makes some cultural traits successful and others not? Research in cultural evolution theory distinguishes factors related to social influence (such as copying from the majority, or from certain individuals) from factors related to individual, nonsocially influenced, propensities such as evolved cognitive predispositions, or physical, biological, and environmental constraints. Here, we show, using analytical and individual-based models, that individual preferences, even when weak, determine the equilibrium point of cultural dynamics when acting together with nondirectional social influence in three out of four cases we study. The results have implications regarding the importance of keeping into account individual-level, nonsocial, factors, when studying cultural evolution, as well as regarding the interpretation of cross-cultural regularities, that must be expected, but can be product of weak directional forces, intensified by social influence.
Analysis of the characteristics of blasting seismic wave induced by explosive blasting with different coupling medium
Volumetric imaging of the 3D orientation of cellular structures with a polarized fluorescence light-sheet microscope
Polarized fluorescence microscopy is a valuable tool for measuring molecular orientations in biological samples, but techniques for recovering three-dimensional orientations and positions of fluorescent ensembles are limited. We report a polarized dual-view light-sheet system for determining the diffraction-limited three-dimensional distribution of the orientations and positions of ensembles of fluorescent dipoles that label biological structures. We share a set of visualization, histogram, and profiling tools for interpreting these positions and orientations. We model the distributions based on the polarization-dependent efficiency of excitation and detection of emitted fluorescence, using coarse-grained representations we call orientation distribution functions (ODFs). We apply ODFs to create physics-informed models of image formation with spatio-angular point-spread and transfer functions. We use theory and experiment to conclude that light-sheet tilting is a necessary part of our design for recovering all three-dimensional orientations. We use our system to extend known two-dimensional results to three dimensions in FM1-43-labeled giant unilamellar vesicles, fast-scarlet-labeled cellulose in xylem cells, and phalloidin-labeled actin in U2OS cells. Additionally, we observe phalloidin-labeled actin in mouse fibroblasts grown on grids of labeled nanowires and identify correlations between local actin alignment and global cell-scale orientation, indicating cellular coordination across length scales.
Publisher Correction: New local magnitude scales for Egypt
Experimental electronic structures of the Fe <sup>IV</sup> =O bond in S=1 heme vs. nonheme sites: Effect of the porphyrin ligand
High-valent Fe IV =O species are common intermediates in biological and artificial catalysts. Heme and nonheme S=1 Fe IV =O sites have been synthesized and studied for decades but little quantitative experimental comparison of their electronic structures has been available, due to the lack of direct methods focused on the iron. This study allows a rigorous determination of the electronic structure of a nonheme Fe IV =O center and its comparison to an Fe IV =O heme site using 1s2p resonant inelastic X-ray scattering (RIXS) and Fe L-edge X-ray absorption spectroscopy (XAS). Further, variable temperature magnetic circular dichroism (VT-MCD) of the ligand field transitions, combined with nuclear resonance vibrational spectroscopy of the two S=1 Fe IV =O systems show that the equatorial ligand field decreases from a nonheme to a heme Fe IV =O site. Alternatively, RIXS and Fe L-edge XAS combined with MCD show that the Fe d π orbitals are unperturbed in the Fe IV =O heme relative to the nonheme site because the strong axial Fe-O bond uncouples the Fe d π orbitals from the porphyrin π -system. As a consequence, the thermodynamics and kinetics of the H-atom abstraction reactions are actually very similar for heme compound II and nonheme Fe IV =O active sites.
Deep neural networks and fractional grey lag Goose optimization for music genre identification
A hormone-to-neuropeptide pathway inhibits sexual receptivity in immature <i>Drosophila</i> females
Newborns, typically asexual, undergo a process of sexual transition to reach sexual maturity, but the regulatory mechanism underlying this transition is not clear. Here, we studied how female sexual behavior is modulated during sexual transition by hormones and neuromodulators in Drosophila . We found that neuropeptide Leucokinin (LK) inhibits female receptivity specifically during a sexual transition period in immature females, but not in younger or mature females. Moreover, the steroid hormone ecdysone, which is mainly synthesized in the female ovary during sexual maturation, acts on LK neurons via the ecdysone receptor to suppress sexual receptivity. We further found that LK suppresses female receptivity through its receptor LKR in central pC1 neurons, a decision center for female sexual behavior. These findings reveal a hormone-to-neuropeptide pathway that specifically inhibits sexual behavior during sexual maturation in female Drosophila , shedding light on how hormones and neuromodulators coordinate sexual development and behaviors.
Discrete element simulation of buzz pollination in tomato
Quantum tunneling and its absence in deep wells and strong magnetic fields
We present results on quantum tunneling between deep potential wells, in the presence of a strong constant magnetic field. We construct a family of double-well potentials containing examples for which the low-energy eigenvalue splitting vanishes, and hence quantum tunneling is eliminated. Further, by deforming within this family, the magnetic ground state can be made to transition from symmetric to antisymmetric. However, for typical double wells in a certain regime, tunneling is not suppressed, and we provide a lower bound for the eigenvalue splitting.
Deformation properties of rock strata based on angular displacement and its hydrogeological significance
Cardiac effects of two hallucinogenic natural products, N,N-dimethyl-tryptamine and 5-methoxy-N,N-dimethyl-tryptamine
Abstract It is unclear whether hallucinogenic tryptamine derivatives namely N,N-dimethyl-tryptamine (DMT) and 5-methoxy-N,N-dimethyl-tryptamine (5-MeO-DMT) exert positive inotropic effects in the human heart. Therefore, we measured the inotropic effects of these drugs in isolated left and right atrial preparations of mice that overexpress human 5-HT4 receptors (5-HT4-TG) and preparations from wild type mice (WT). Moreover, we measured force of contraction in isolated right atrial preparations from adult patients, obtained in the process of open heart surgery due to severe coronary heart disease. DMT and 5-MeO-DMT augmented the force of contraction in isolated paced (1 Hz) left atrial preparations from 5-HT4-TG and raised the spontaneous beating rate of right atrial preparations from 5-HT4-TG. The drugs elevated force of contraction in paced (1 Hz) human right atrial muscle preparations. The maximum inotropic effects of DMT and 5-MeO-DMT were smaller at 10 µM (about 65%) than that of 1 µM 5-HT on the left atria from 5-HT4-TG. The maximum increase in the beating rate due to DMT and 5-MeO-DMT amounted 40 ± 5% of the effect of 5-HT on right atrial preparations from 5-HT4-TG (n = 5–6). DMT and 5-MeO-DMT were inactive in WT. The potency of 5-MeO-DMT to increase force of contraction could be increased by pre-treatment of human atrial preparations by the phosphodiesterase inhibitor cilostamide (1 µM). 5-MeO-DMT increased the phosphorylation state of phospholamban at serine 16 in isolated left atrial muscle strips of 5-HT4-TG. In summary, DMT and 5-MeO-DMT acted as partial agonists on human 5-HT4 receptors.
Entanglement transition in random rod packings
Random packings of stiff rods are self-supporting mechanical structures stabilized by long-range interactions induced by contacts. To understand the geometrical and topological complexity of the packings, we first deploy X-ray computerized tomography to unveil the structure of the packing. This allows us to directly visualize the spatial variations in density, orientational order, and the entanglement, a mesoscopic field that we define in terms of a local average crossing number, a measure of the topological complexity of the packing. We find that increasing the aspect ratio of the constituent rods in a packing leads to a proliferation of regions of strong entanglement that eventually percolate through the system and correlated with a sharp transition in the mechanical stability of the packing. To corroborate our experimental findings, we use numerical simulations of contacting elastic rods and characterize their stability to static and dynamic loadings. Our experiments and computations lead us to an entanglement phase diagram which we also populate using published experimental data from pneumatically tangled filaments, worm blobs, and bird nests along with additional numerical simulations using these datasets. Together, these show the regimes associated with mechanically stable entanglement as a function of the statistics of the packings and loading, with lessons for a range of systems from reconfigurable architectures and textiles to active morphable filamentous assemblies.
Development and synthesis of diffractaic acid analogs as potent inhibitors of colorectal cancer stem cell traits
STING-induced noncanonical autophagy regulates endolysosomal homeostasis
The cGAS–STING pathway mediates innate immune responses to cytosolic DNA. In addition to its well-established role in inducing inflammatory cytokines, activation of the cGAS–STING pathway also induces noncanonical autophagy, a process involving the conjugation of the ATG8 family of ubiquitin-like proteins to membranes of the endolysosomal system. The mechanisms and functions of STING-induced autophagy remain poorly understood. In this study, we demonstrated that STING activation induced formation of pH-elevated Golgi-derived vesicles that led to ATG16L1 and V-ATPase-dependent noncanonical autophagy. We showed that STING-induced noncanonical autophagy resulted in activation of the MiT/TFE family of transcription factors (TFEB, TFE3, and MITF), which regulate lysosome biogenesis. We found that lipidation of the ATG8 proteins, particularly GABARAPs, inhibited phosphorylation of MiT/TFE transcription factors by mTORC1. The lipidated GABARAPs bound to the Folliculin-interacting proteins (FNIPs), thereby sequestering the FNIP-folliculin protein complexes from activating mTORC1, resulting in dephosphorylation and nuclear translocation of MiT/TFE transcription factors. Furthermore, we found that STING-induced autophagy activated Leucine-rich repeat kinase 2 (LRRK2), a protein implicated in Parkinson’s disease, through GABARAPs lipidation. We further showed that STING-induced autophagy induced ALIX-mediated ESCRT machinery recruitment to mitigate endolysosomal perturbation. These results reveal the multifaceted functions of STING-induced noncanonical autophagy in regulating endolysosomal homeostasis.