Alchemical and structural distribution based representation for improved QML

We introduce a representation of any atom in any chemical environment for the generation of efficient quantum machine learning (QML) models of common electronic ground-state properties. The representation is based on scaled distribution functions explicitly accounting for elemental and structural degrees of freedom. Resulting QML models afford very favorable learning curves for properties of out-of-sample systems including organic molecules, non-covalently bonded protein side-chains, (H$_2$O)$_{40}$-clusters, as well as diverse crystals. The elemental components help to lower the learning curves, and, through interpolation across the periodic table, even enable "alchemical extrapolation" to covalent bonding between elements not part of training, as evinced for single, double, and triple bonds among main-group elements

Oridonin nanosuspension was more effective than free oridonin on G2/M cell cycle arrest and apoptosis in the human pancreatic cancer PANC-1 cell line

Oridonin, a diterpenoid isolated from Rabdosia rubescencs, has been reported to have antitumor effects. However, low solubility has limited its clinical applications. Preparation of drugs in the form of nanosuspensions is an extensively utilized protocol. In this study, we investigated the anticancer activity of oridonin and oridonin nanosuspension on human pancreatic carcinoma PANC-1 cells. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to investigate the effect of oridonin on cell growth. Propidium iodide and Hoechst 33342 staining were used to detect morphologic changes. The percentage of apoptosis and cell cycle progression was determined by flow cytometric method staining with propidium iodide. Annexin V-fluorescein isothiocyanate (FITC)/PI staining was used to evaluate cell apoptosis by flow cytometry. Caspase-3 activity was measured by spectrophotometry. The apoptotic and cell cycle protein expression were determined by Western blot analysis. Both oridonin and oridonin nanosuspension induced apoptosis and G2/M phase cell cycle arrest, and the latter had a more significant cytotoxic effect. The ratio of Bcl-2/Bax protein expression was decreased and caspase- 3 activity was stimulated. The expression of cyclin B1 and p-cdc2 (T161) was suppressed. Our results showed that oridonin nanosuspension was more effective than free oridonin on G2/M cell cycle arrest and apoptosis in the human pancreatic cancer PANC-1 cell line

RbSn2(PO4)3, a NASICON-type phosphate

The title compound, rubidium ditin(IV) tris­(phosphate), RbSn2(PO4)3, belongs to the NASICON-type family of phosphates and crystallizes in the space group R . The structure is composed of PO4 tetra­hedra (1 symmetry) and two slightly distorted SnO6 octa­hedra, both with 3. symmetry, which are inter­linked through corner-sharing O atoms to form a 3 ∞[Sn2(PO4)3]− framework. The Rb+ cations are located on threefold inversion axes in the voids of this framework and exhibit a coordination number of 12. The crystal studied was twinned by merohedry with a component ratio of 0.503:0.497

Acceleration and displacement dynamic response laws of a shallow-buried bifurcated tunnel

In order to obtain the seismic dynamic laws of the acceleration and displacement of a shallow-buried bifurcated tunnel, the analysis of the numerical simulation was carried out by MIDAS-GTS/NX software. The results of the numerical simulation were verified by a shaking table model test. The results show that: (1) the numerical simulation and shaking table test coincide with each other in terms of variation law and peak value. The results of the numerical simulation are credible. (2) For different tunnel cross-section, the response of acceleration and displacement are significant difference. (3) The seismic response of the small distance tunnel (Section 6) is intense. The seismic response laws of the small distance tunnel are significant difference from other type tunnels. The seismic response of the measuring point at the middle rock column is intense. (4) Along the axis of the tunnel, the displacement of the tunnel firstly increases and then decreases. The displacement of the measuring point at the middle rock column is intense, which is in accordance with the law of the acceleration response. The seismic response laws of the tunnel are significantly affected by the middle rock column. The section structure size has a significant effect on the dynamic response of the tunnel

Convolutional neural network based on photoplethysmography signals for sleep apnea syndrome detection

IntroductionThe current method of monitoring sleep disorders is complex, time-consuming, and uncomfortable, although it can provide scientifc guidance to ensure worldwide sleep quality. This study aims to seek a comfortable and convenient method for identifying sleep apnea syndrome.MethodsIn this work, a one-dimensional convolutional neural network model was established. To classify this condition, the model was trained with the photoplethysmographic (PPG) signals of 20 healthy people and 39 sleep apnea syndrome (SAS) patients, and the influence of noise on the model was tested by anti-interference experiments.Results and DiscussionThe results showed that the accuracy of the model for SAS classifcation exceeds 90%, and it has some antiinterference ability. This paper provides a SAS detection method based on PPG signals, which is helpful for portable wearable detection

Atomistic basis of opening and conduction in mammalian inward rectifier potassium (Kir2.2) channels

Potassium ion conduction through open potassium channels is essential to control of membrane potentials in all cells. To elucidate the open conformation and hence the mechanism of K+ ion conduction in the classic inward rectifier Kir2.2, we introduced a negative charge (G178D) at the crossing point of the inner helix bundle, the location of ligand-dependent gating. This forced open mutation generated channels that were active even in the complete absence of phosphatidylinositol-4,5-bisphosphate (PIP2), an otherwise essential ligand for Kir channel opening. Crystal structures were obtained at a resolution of 3.6 Å without PIP2 bound, or 2.8 Å in complex with PIP2. The latter revealed a slight widening at the helix bundle crossing (HBC) through backbone movement. MD simulations showed that subsequent spontaneous wetting of the pore through the HBC gate region allowed K+ ion movement across the HBC and conduction through the channel. Further simulations reveal atomistic details of the opening process and highlight the role of pore-lining acidic residues in K+ conduction through Kir2 channels

Genome-Wide Characterization of Endogenous Retroviruses in Bombyx mori Reveals the Relatives and Activity of env Genes

Endogenous retroviruses (ERVs) are retroviral sequences that remain fixed in the host genome, where they could play an important role. Some ERVs have been identified in insects and proven to have infectious properties. However, no information is available regarding Bombyx mori ERVs (BmERVs) to date. Here, we systematically identified 256 potential BmERVs in the silkworm genome via a whole-genome approach. BmERVs were relatively evenly distributed across each of the chromosomes and accounted for about 25% of the silkworm genome. All BmERVs were classified as young ERVs, with insertion times estimated to be less than 10 million years. Seven BmERVs possessing the env genes were identified. With the exception of the Orf133 Helicoverpa armigera nuclear polyhedrosis virus, the env sequences of BmERVs were distantly related to genes encoding F (Fa and Fb) and GP64 proteins from Group I and Group II NPVs. In addition, only the amino acid sequence of the BmERV-21 envelope protein shared a similar putative furin-like cleavage site and fusion peptide with Group II baculoviruses. All of the env genes in the seven BmERVs were verified to exist in the genome and be expressed in the midgut and fat bodies, which suggest that BmERVs might play an important role in the host biology

Mechanism of Subordinate Peak Skewing of FBG Sensor during Cracks Propagation Monitoring on Aluminum Alloy Structure

This study investigates the variety of the spectra features of fiber Bragg grating (FBG) around the crack tip during fatigue crack propagation. The study results reveal that the turning of the subordinate peak is significantly associated with crack lengths and corresponds to strain gradient along the FBG. Meanwhile, the strain distribution sensed by the FBG changes with the sensing section of the grating. FBG sensors could observe the monotonic plastic zone ahead of the fatigue crack tip. The cubic strain is distributed along the grating, with monotonic plastic zone propagation at the initial and terminal part of the grating, at approximately a 30% ratio of the entire grating. However, the monotonic plastic zone is sensed by the FBG, at ±15% bias of the grating center, with the quadratic strain gradient pattern along the grating. In particular, when the initial and terminal parts of the grating experience highly inhomogeneous strain distribution, the spectrum distortion occurs

Experimental study on acceleration response laws of shallow-buried bias tunnels with a small distance

Based on the similarity theory, a physical testing model with scale of 1:10 was designed and fabricated. The Wenchuan wave (WC-XZ), Darui artificial wave (DR-XZ) and Kobe wave (K-XZ) were adopted as excitation waves which was XZ directions (horizontal and vertical loading at the same time). A series of shaking table tests were carried out to study the effect of the types, directions and peaks acceleration of the seismic waves on the acceleration response laws of the shallow-buried bias tunnels with small distance. The results show that: (1) in the horizontal direction, the types of the seismic waves have a little effect on the acceleration response, but the law is opposite with Kobe wave being the most serious, followed by Darui artificial wave and Wenchuan wave in the vertical direction. (2) The existing slope has a significant effect on the acceleration response of the right hole which is different from that of the left hole. (3) The acceleration response of the tunnel in the vertical direction is more severe than that of the horizontal direction and the acceleration amplification factors in vertical direction are is generally 1.02-3.94 times that of the horizontal direction. (4) in the seismic design of tunnel, different seismic measures should be adopted in different directions. The results have a significant reference for the anti-seismic design of the tunnel