The single-walled carbon nanotubes (SWNTs) filled nanocomposite SWNT/epoxy resin composite with good uniformity, dispersion and alignment of SWNTs and with different SWNTs concentrations was produced ...by solution casting technique. Subsequently, the semidried mixture was stretched repeatedly along one direction at a large draw-ratio of 50 for 100 times at ambient atmosphere manually to achieve a good alignment and to promote dispersion of SWNTs in the composite matrix. Composite showed higher electrical conductivities and mechanical properties such as the Young’s modulus and tensile strength along the stretched direction than perpendicular to it, and the electrical property of composite rise with the increase of SWNT concentration. The percolation threshold value of electrical conductivity along the stretching direction is lower than the value perpendicular to the SWNTs orientation. In addition, the anisotropic electric and mechanical properties results, SEM micrograph and the polarized Raman spectra of the SWNT/epoxy composite reveal that SWNTs were well dispersed and aligned in the composites by the repeated stretching process.
The prediction of drug–target affinity (DTA) is a crucial step for drug screening and discovery. In this study, a new graph-based prediction model named SAG-DTA (self-attention graph drug–target ...affinity) was implemented. Unlike previous graph-based methods, the proposed model utilized self-attention mechanisms on the drug molecular graph to obtain effective representations of drugs for DTA prediction. Features of each atom node in the molecular graph were weighted using an attention score before being aggregated as molecule representation. Various self-attention scoring methods were compared in this study. In addition, two pooing architectures, namely, global and hierarchical architectures, were presented and evaluated on benchmark datasets. Results of comparative experiments on both regression and binary classification tasks showed that SAG-DTA was superior to previous sequence-based or other graph-based methods and exhibited good generalization ability.
Condition-based molecular generation can generate a large number of molecules with particular properties, expanding the virtual drug screening library, and accelerating the process of drug discovery. ...In this study, we combined a molecular graph structure and sequential representations using a generative pretrained transformer (GPT) architecture for generating molecules conditionally. The incorporation of graph structure information facilitated a better comprehension of molecular topological features, and the augmentation of a sequential contextual understanding of GPT architecture facilitated molecular generation. The experiments indicate that our model efficiently produces molecules with the desired properties, with valid and unique metrics that are close to 100%. Faced with the typical task of generating molecules based on a scaffold in drug discovery, our model is able to preserve scaffold information and generate molecules with low similarity and specified properties.
Phosphorus-containing polybutylene succinate (P-PBS) was prepared from the third monomer phenylphosphonic acid to improve the performance of biodegradable materials and endow plants with nutritional ...functions. The P-PBS/polylactic acid (PLA) composite was produced by blending P-PBS and PLA; its crystallization, thermodynamic, water vapor permeability, degradation, and plant nutrition properties were studied. Introducing phenylphosphoric acid destroyed the regularity of the PBS chain, decreased the crystallinity, and increased the polarity. With PLA, the composite crystallinity was further reduced. A certain intermolecular force combines P-PBS/PLA. When the P-PBS amount was 60%, the two-phase melting point was close, the two-phase compatibility was high, and the crystallinity was the lowest. Additionally, the molecular chain flexibility of the composite was the highest with the optimal thermal and mechanical properties. Furthermore, with 60% P-PBS, the composite material had the highest water vapor transmission rate for possessing the largest two-phase contact surface, which can be used as a mulching film. The composite was degraded in soil supernatant for 6 months, with a 60%–70% degradation rate. LC-MS identification revealed that the degradation products were succinic acid, butanediol, and phenylphosphonic acid oligomers, among which phosphorus-containing small molecules enhanced lettuce growth.
•Phosphorus-containing polybutylene succinate (P-PBS) was prepared.•The prepared P-PBS had improved biodegradability and nutrition functionality.•Optimized P-PBS composition gave high two-phase compatibility and low crystallinity.•Degradation composite products had P-containing molecules, aiding lettuce growth.
This study aimed to retrospectively analyze the perioperative and postoperative follow-up data of patients with super obesity who had undergone RYGB, SG, BPD/DS, and SADI-S. A retrospective ...observational study was conducted to analyze the perioperative and postoperative follow-up data of 60 patients with super obesity who had undergone bariatric surgery. A total of 34 men and 26 women were included in this study. The participants had an average preoperative BMI of 53.81 ± 3.25 kg/m
. The body weight and BMI of all four patient groups decreased significantly at 3, 6, and 12 months postoperatively compared with the preoperative values. Additionally, the TWL (%) and EWL (%) of all four groups increased gradually over the same period. Compared with the preoperative values, the systolic and diastolic blood pressure, glycosylated hemoglobin, uric acid, triglycerides, and total cholesterol decreased to varying degrees in the four groups 1 year postoperatively. RYGB, SG, BPD/DS, and SADI-S are all safe and effective in treating super obese patients and improving their metabolic diseases to a certain extent.
In order to find the optimum climb parameters for decreasing aircraft pollution emissions, we establish a calculation model of aircraft pollutant emissions to thoroughly examine the economy of ...aircraft operation and its impact on the environment, based on the International Civil Aviation Organization reference emission data and Boeing Method 2 which can calculate pollutant emissions in different flight phases by correcting the ICAO emission data. Firstly, we propose the concept of integrated flight cost considering the effect of emissions and establish its calculation model. Secondly, we establish the climb speed optimization models based on the traditional flight cost and integrated flight cost. Then, we analyze the effect of climb performance on the integrated flight cost. Next, we establish a combined optimization model of indicated airspeed and thrust using the genetic algorithm. The model simulation and result analysis are carried out using a wide-body aircraft. Finally, we analyze the effect of the optimization parameters and the sensitivity of the pollution index. The results show that the decrease in the flight speed and thrust effectively reduces the cost of pollutant emission during flight. The combination of (Vc, Tr) with the smallest integrated flight cost reduces the integrated flight cost by 1.28% and emission cost by 4.56%.
In this paper, the MnO2/three-dimensional carbon nanotubes-graphene nanocomposite was synthesized on Cu foil substrate by chemical vapor deposition and subsequent thermal decomposition of manganese ...acetyllacetonate precursors. The nanocomposite material was directly used as a binder-free electrode to investigate the supercapacitive performance. The results indicate that the appropriate defects and MnO2 nanoparticles are introduced simultaneously into the carbon nanotubes-graphene architecture in one-step. The specific capacitance of MnO2/three-dimensional carbon nanotubes-graphene/Cu electrode is up to 365 F g−1 at a current density of 1 A g−1 in 1.0 M Na2SO4 solution, which is 9 times higher than that of electrode without MnO2 modification. After 1000 cycles at 1 A g−1, the capacity retention is still maintained at 97.0%, suggesting potential applications in high-performance energy storage devices. The excellent electrochemical performances of nanocomposite electrode can be attributed to the significantly synergistic effects between the lasting electronic conductivity of three-dimensional carbon nanotubes-graphene/Cu with the appropriate defects and the pseudocapacitance of the MnO2 nanoparticles.
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•MnO2/3D CNTs-G/Cu was fabricated as a binder-free electrode using a facile method.•Defects and α-MnO2 was introduced simultaneously into the 3D CNTs-G/Cu in one-step.•The specific capacitance of MnO2/3D CNTs-G/Cu reached 365 F g−1 at 1 A g−1 current.•Synergistic effects of 3D CNTs-G/Cu lasting conductivity and MnO2 pseudocapacitance.
This study provides a 16.2-kyr record of mercury (Hg) deposition derived from a lacustrine sedimentary sequence in Dahu Swamp, eastern Nanling Mountains. Results indicate that changes in climatic ...conditions had a significant effect on Hg concentrations (Hg–C) and accumulation rates (Hg-AR). Multi-proxy records including dry density, grain size, geochemical elements, organic matter and pollen indicators were compared with Hg accumulation. The results revealed that the contributions of detrital input and atmospheric deposition were minor, and Hg accumulation in the sediments was closely related to changes in climatic conditions: relatively drier and colder climate would result in shrinkage of the lake water body thus favoring increased formation of organic-rich peat or gyttja and leading to enhanced absorption of Hg by organic matter and result in increases of Hg–C and Hg-AR in sediments, and vice versa. Our results indicate that variations of Hg accumulation in Dahu Swamp were greatly impacted by climate under the influences of solar insolation changes and shrinkage or expansion of ice sheets in high latitudes to the north. The results of this study provide an insight into the response of Hg accumulation to low latitude climate processes in the East Asian summer monsoon region.
In this study, a new approach using a novel ensemble classification algorithm based on ECG morphological features is proposed for accurate detection of heart ventricular and atrial abnormalities. ...First, the raw ECG signal is preprocessed and the main character waves are detected. Second, a combination of ECG morphological features is proposed and extracted from the selected ECG segments. The proposed feature set contains morphological parameters, morphological visual pattern of QRS complex, and principle components of the third level and fourth level of a four-level Sym8 wavelet-decomposed ECG waveform. Next, a novel ensemble classification algorithm, with the key idea of integrating the knowledge acquired by several popular classification algorithms for this task into an ensemble system, is proposed so that the accuracy and robustness over various arrhythmia types could be improved. Finally, the features are applied to the proposed ensemble classification algorithm for abnormality detection. The proposed approach achieved an overall accuracy of 98.68% when it was validated on fifteen heartbeat types from the MIT-BIH arrhythmia database (MITDB), according to the Association for Advancement of Medical Instrumentation (AAMI) standard. The classification accuracies of the six main types - normal beat (N), right bundled branch blocks beat (R), left bundled branch blocks beat (L), atrial premature beat (A), premature ventricular contractions beat (V), and paced beat (P) are 98.75%, 99.77%, 99.70%, 94.81%, 98.57%, and 99.94%, respectively. The proposed approach proves a solid result in comparison with component classification algorithms as well as recent peer works.
Inflammatory bowel disease (IBD) is an idiopathic and persistent inflammatory illness of the bowels, leading to a substantial burden on both society and patients due to its high incidence and ...recurrence. The pathogenesis of IBD is multifaceted, partly attributed to the imbalance of immune responses toward the gut microbiota. There is a correlation between the severity of the disease and the imbalance in the oral microbiota, which has been discovered in recent research highlighting the role of oral microbes in the development of IBD. In addition, various oral conditions, such as angular cheilitis and periodontitis, are common extraintestinal manifestations (EIMs) of IBD and are associated with the severity of colonic inflammation. However, it is still unclear exactly how the oral microbiota contributes to the pathogenesis of IBD. This review sheds light on the probable causal involvement of oral microbiota in intestinal inflammation by providing an overview of the evidence, developments, and future directions regarding the relationship between oral microbiota and IBD. Changes in the oral microbiota can serve as markers for IBD, aiding in early diagnosis and predicting disease progression. Promising advances in probiotic-mediated oral microbiome modification and antibiotic-targeted eradication of specific oral pathogens hold potential to prevent IBD recurrence.
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