Accurate prediction of heat conductivity of water by a neuroevolution potential

We propose an approach that can accurately predict the heat conductivity of liquid water. On the one hand, we develop an accurate machine-learned potential based on the neuroevolution-potential approach that can achieve quantum-mechanical accuracy at the cost of empirical force fields. On the other hand, we combine the Green-Kubo method and the spectral decomposition method within the homogeneous nonequilibrium molecular dynamics framework to account for the quantum-statistical effects of high-frequency vibrations. Excellent agreement with experiments under both isobaric and isochoric conditions within a wide range of temperatures is achieved using our approach.Comment: 8 pages, 7 figure

Trefoil Factor 3, Cholinesterase and Homocysteine: Potential Predictors for Parkinson\u27s Disease Dementia and Vascular Parkinsonism Dementia in Advanced Stage

Trefoil factor 3 (TFF3), cholinesterase activity (ChE activity) and homocysteine (Hcy) play critical roles in modulating recognition, learning and memory in neurodegenerative diseases, such as Parkinson\u27s disease dementia (PDD) and vascular parkinsonism with dementia (VPD). However, whether they can be used as reliable predictors to evaluate the severity and progression of PDD and VPD remains largely unknown. METHODS: We performed a cross-sectional study that included 92 patients with PDD, 82 patients with VPD and 80 healthy controls. Serum levels of TFF3, ChE activity and Hcy were measured. Several scales were used to rate the severity of PDD and VPD. Receivers operating characteristic (ROC) curves were applied to map the diagnostic accuracy of PDD and VPD patients compared to healthy subjects. RESULTS: Compared with healthy subjects, the serum levels of TFF3 and ChE activity were lower, while Hcy was higher in the PDD and VPD patients. These findings were especially prominent in male patients. The three biomarkers displayed differences between PDD and VPD sub-groups based on genders and UPDRS (III) scores\u27 distribution. Interestingly, these increased serum Hcy levels were significantly and inversely correlated with decreased TFF3/ChE activity levels. There were significant correlations between TFF3/ChE activity/Hcy levels and PDD/VPD severities, including motor dysfunction, declining cognition and mood/gastrointestinal symptoms. Additionally, ROC curves for the combination of TFF3, ChE activity and Hcy showed potential diagnostic value in discriminating PDD and VPD patients from healthy controls. CONCLUSIONS: Our findings suggest that serum TFF3, ChE activity and Hcy levels may underlie the pathophysiological mechanisms of PDD and VPD. As the race to find biomarkers or predictors for these diseases intensifies, a better understanding of the roles of TFF3, ChE activity and Hcy may yield insights into the pathogenesis of PDD and VPD

Sub-micrometer phonon mean free paths in metal-organic frameworks revealed by machine-learning molecular dynamics simulations

Metal-organic frameworks (MOFs) are a family of materials that have high porosity and structural tunability and hold great potential in various applications, many of which requiring a proper understanding of the thermal transport properties. Molecular dynamics (MD) simulations play an important role in characterizing the thermal transport properties of various materials. However, due to the complexity of the structures, it is difficult to construct accurate empirical interatomic potentials for reliable MD simulations of MOFs. To this end, we develop a set of accurate yet highly efficient machine-learned potentials for three typical MOFs, including MOF-5, HKUST-1, and ZIF-8, using the neuroevolution potential approach as implemented in the GPUMD package, and perform extensive MD simulations to study thermal transport in the three MOFs. Although the lattice thermal conductivity (LTC) values of the three MOFs are all predicted to be smaller than 1 $\rm{W/(m\ K)}$ at room temperature, the phonon mean free paths (MFPs) are found to reach the sub-micrometer scale in the low-frequency region. As a consequence, the apparent LTC only converges to the diffusive limit for micrometer single crystals, which means that the LTC is heavily reduced in nanocrystalline MOFs. The sub-micrometer phonon MFPs are also found to be correlated with a moderate temperature dependence of LTC between those in typical crystalline and amorphous materials. Both the large phonon MFPs and the moderate temperature dependence of LTC fundamentally change our understanding of thermal transport in MOFs.Comment: 12 pages, 9 figure

Blood Meal Acquisition Enhances Arbovirus Replication in Mosquitoes Through Activation of the GABAergic System

Mosquitoes are hematophagous insects that carry-on and transmit many human viruses. However, little information is available regarding the common mechanisms underlying the infection of mosquitoes by these viruses. In this study, we reveal that the hematophagous nature of mosquitoes contributes to arboviral infection after a blood meal, which suppresses antiviral innate immunity by activating the GABAergic pathway. dsRNA-mediated interruption of the GABA signaling and blockage of the GABAA receptor by the specific inhibitors both significantly impaired arbovirus replication. Consistently, inoculation of GABA enhanced arboviral infection, indicating that GABA signaling facilitates the arboviral infection of mosquitoes. The ingestion of blood by mosquitoes resulted in robust GABA production from glutamic acid derived from blood protein digestion. The oral introduction of glutamic acid increased virus acquisition by mosquitoes via activation of the GABAergic system. Our study reveals that blood meals enhance arbovirus replication in mosquitoes through activation of the GABAergic system

Cattle Mammary Bioreactor Generated by a Novel Procedure of Transgenic Cloning for Large-Scale Production of Functional Human Lactoferrin

Large-scale production of biopharmaceuticals by current bioreactor techniques is limited by low transgenic efficiency and low expression of foreign proteins. In general, a bacterial artificial chromosome (BAC) harboring most regulatory elements is capable of overcoming the limitations, but transferring BAC into donor cells is difficult. We describe here the use of cattle mammary bioreactor to produce functional recombinant human lactoferrin (rhLF) by a novel procedure of transgenic cloning, which employs microinjection to generate transgenic somatic cells as donor cells. Bovine fibroblast cells were co-microinjected for the first time with a 150-kb BAC carrying the human lactoferrin gene and a marker gene. The resulting transfection efficiency of up to 15.79×10−2 percent was notably higher than that of electroporation and lipofection. Following somatic cell nuclear transfer, we obtained two transgenic cows that secreted rhLF at high levels, 2.5 g/l and 3.4 g/l, respectively. The rhLF had a similar pattern of glycosylation and proteolytic susceptibility as the natural human counterpart. Biochemical analysis revealed that the iron-binding and releasing properties of rhLF were identical to that of native hLF. Importantly, an antibacterial experiment further demonstrated that rhLF was functional. Our results indicate that co-microinjection with a BAC and a marker gene into donor cells for somatic cell cloning indeed improves transgenic efficiency. Moreover, the cattle mammary bioreactors generated with this novel procedure produce functional rhLF on an industrial scale

Draft genome sequence of the mulberry tree Morus notabilis

Human utilization of the mulberry–silkworm interaction started at least 5,000 years ago and greatly influenced world history through the Silk Road. Complementing the silkworm genome sequence, here we describe the genome of a mulberry species Morus notabilis. In the 330-Mb genome assembly, we identify 128 Mb of repetitive sequences and 29,338 genes, 60.8% of which are supported by transcriptome sequencing. Mulberry gene sequences appear to evolve ~3 times faster than other Rosales, perhaps facilitating the species’ spread worldwide. The mulberry tree is among a few eudicots but several Rosales that have not preserved genome duplications in more than 100 million years; however, a neopolyploid series found in the mulberry tree and several others suggest that new duplications may confer benefits. Five predicted mulberry miRNAs are found in the haemolymph and silk glands of the silkworm, suggesting interactions at molecular levels in the plant–herbivore relationship. The identification and analyses of mulberry genes involved in diversifying selection, resistance and protease inhibitor expressed in the laticifers will accelerate the improvement of mulberry plants

Atomistic insights into the mechanical anisotropy and fragility of monolayer fullerene networks using quantum mechanical calculations and machine-learning molecular dynamics simulations

In this work, we comprehensively study the mechanical properties of the newly synthesised monolayer quasi-hexagonal-phase fullerene (qHPF) membrane [Nature \textbf{606}, 507-510 (2022)] under uniaxial tension by using quantum mechanical density-functional-theory (DFT) calculations and molecular dynamics (MD) simulations with a machine-learned neuroevolution potential (NEP). The elastic properties and fracture behaviours of monolayer qHPF are found to be strongly anisotropic due to the different properties between the inter-fullerene C-C single bonds and [2 + 2] cycloaddition bonds. Moreover, the tensile strength and fracture strain of monolayer qHPF are much smaller than those of any other existing two-dimensional (2D) carbon crystals. The very small tensile strength or fracture strain is ascribed to the inhomogeneous deformation of the stretched monolayer qHPF, which originates from the stiffness difference between the soft inter-fullerene bonds and the rigid intra-fullerene bonds. Compared with DFT calculations at the ground state, the NEP-based extensive MD simulations predict a much smaller tensile strength and fracture strain for monolayer qHPF due to their consideration of the effects of temperature and membrane size. Our work not only reveals the underlying mechanism of the fracture behaviours of monolayer fullerene networks from an atomistic perspective, but also shows the effectiveness and accuracy of the NEP approach in determining the mechanical properties of 2D materials in the realistic situations

Thermal transport in planar sp2-hybridized carbon allotropes: A comparative study of biphenylene network, pentaheptite and graphene

The biphenylene network with periodically arranged four-, six-, and eightmembered rings has been successfully synthesized in very recent experiments. This novel two-dimensional (2D) carbon allotrope has potentials in applications of lithium storage and carbon-based circuitry. Understanding the thermal transport properties of biphenylene network is of critical importance for the performance and reliability of its practical applications. To this end, the thermal transport in biphenylene network is comprehensively investigated in this paper with the aid of molecular dynamics simulations together with first-principles calculations. For the sake of comparison, the thermal conductivities of other 2D sp2-hybridized carbon allotropes including graphene and pentaheptite are also investigated using the same method. It is found that the thermal conductivities of biphenylene network and pentaheptite are, respectively, only about one-thirteenth and one-eighth of graphene. Through the analysis of phonon property, mechanical property and electron density distribution, it is demonstrated that the great reduction in the thermal conductivity of biphenylene network and pentaheptite arises from the decline in their structural symmetry, which leads to the decrease of phonon group velocity and the reduction of phonon mean free path

The value of the ACEF II score in Chinese patients with elective and non-elective cardiac surgery

Abstract Objective To evaluate the value of the ACEF II score in predicting postoperative hospital death and acute kidney injury requiring dialysis (AKI-D) in Chinese patients. Methods This retrospective study included adult patients who underwent cardiopulmonary bypass open heart surgery between January 2010 and December 2015 at Guangdong Provincial People’s Hospital. ACEF II was evaluated to predict in-hospital death and AKI-D using the Hosmer–Lemeshow goodness of fit test for calibration and area under the receiver operating characteristic (ROC) curve for discrimination in non-elective and elective cardiac surgery. Results A total of 9748 patients were included. Among them, 1080 underwent non-elective surgery, and 8615 underwent elective surgery. Mortality was 1.8% (177/9748). In elective surgery, the area under the ROC (AUC) of the ACEF II score was 0.704 (95% CI: 0.648–0.759), similar to the ACEF score of 0.709 (95% CI: 0.654–0.763). In non-elective surgery, the AUC of the ACEF II score was 0.725 (95% CI: 0.663–0.787), higher than the ACEF score (AUC = 0.625, 95% CI: 0.553–0.697). The incidence of AKI-D was 3.5% (345/9748). The AUC of the ACEF II score was 0.718 (95% CI: 0.687–0.749), higher than the ACEF score (AUC = 0.626, 95% CI: 0.594–0.658). Conclusion ACEF and ACEF II have poor discrimination ability in predicting AKI-D in non-elective surgery. The ACEF II and ACEF scores have the same ability to predict in-hospital death in elective cardiac surgery, and the ACEF II score is better in non-elective surgery. The ACEF II score can be used to assess the risk of AKI-D in elective surgery in Chinese adults

A novel molybdenum-based nanocrystal decorated ceramic membrane for organics degradation via catalytic wet air oxidation (CWAO) at ambient conditions

Catalytic wet air oxidation (CWAO), one of the best-known methods for water treatment, has been intensely investigated for dyes degradation. However, the extreme operation conditions as well as the recovery of suspended catalyst are economically unattractive. In the current work, a novel Mo-based nanocrystal decorated ceramic membrane (Mo/Al2O3) has been prepared and applied for organics degradation via CWAO at ambient conditions for the first time. The catalytic Mo/Al2O3 membranes were prepared by an in-situ hydrothermal followed by calcination method. Their physical and chemical properties were characterized by field emission scanning electron microscope (FESEM), X-rays diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS). The catalytic performance of Mo/Al2O3 membranes were evaluated via organics (safranine O and humic acid) degradation under a home-made membrane filtration system. The effects of calcination temperature, catalyst loading amount, and trans-membrane pressure (TMP) were systematically investigated. The stability and durability of the catalytic Mo/Al2O3 membrane were examined in a long-term filtration system. Results showed that the performance of Mo/Al2O3 membrane would decrease with increasing of calcination temperature as well as TMP. However, the catalyst loading amount was not a major effect on the removal of organics in the system. For one-time loading membrane calcined at 300 °C (1x-Mo/Al2O3 membrane@300), the removal efficiency could achieve higher than 90 % in 40 min in a recycled filtration system with an initial safranine O concentration of 10 mg L−1. The chemical quenching experiment as well as radical quantification verified the main reactive oxygen species were 1O2 and [rad]O2− in the system. The ROS generation mechanism was proposed via the characterization of the catalyst after reaction. The deliberate combination of CWAO and membrane separation represents a new strategy that offers exciting possibilities for water treatment under ambient conditions.Nanyang Technological UniversityFinancial support for this project is provided by the Ph.D. research scholarship from NTU