The second pressure and acoustic virial coefficients of helium-4 and helium-3 are computed employing an accurate ab initio potential from the literature. The fully quantum-mechanical formulations are ...derived for second acoustic virial coefficient, which are not available in the literature. The uncertainty of our calculated values is quantified and evaluated based on the potential inaccuracy. For helium-4, our theoretical values are in excellent agreement with the best measurements and a recent ab initio calculation. Our estimated uncertainty is at least five times smaller than the previous best determination. For helium-3, systematic errors are detected for the widely accepted ab initio data and our new results are probably more reliable. The computed values of this work are given in the supplemental materials over a wide temperature range between 1 and 10 000 K, which are useful especially for primary temperature metrology.
Composition engineering of perovskite materials has been demonstrated to be important for high‐performance solar cells. Recently, the energy favorable hybridization of formamidinium (FA) and cesium ...(Cs) in three dimension lead halide perovskites has been attracting increasing attention due to its potential benefit on durability. Herein, we reported a simple and effective method to produce phase‐pure CsxFA1‐xPbI3 thin film via sequential introduction of cations, in which the FA cation was introduced by interdiffusion annealing in the presence of N‐methylimidazole (NMI). NMI was employed as an additive to slow down the crystallization and thus drive the formation of CsxFA1‐xPbI3 with micrometer grain size, which probably facilitate the charge dissociation and transportation in photovoltaic devices. More importantly, composition dependent phase‐segregation has been revealed and investigated for the first time during the phase‐pure mixed‐cation perovskites CsxFA1‐xPbI3. The present findings demonstrated that suppressing phase‐segregation of mixed‐cation perovskites by meticulous composition engineering is significant for further development of efficient photovoltaics. It also suggested that phase‐pure Cs0.15FA0.85PbI3 may be a promising candidate with superior phase‐durability, which performed an efficiency over 16% in planar perovskite solar cells.
An effective method to produce phase‐pure CsxFA1−xPbI3 thin film via sequential introduction of cations is reported. More importantly, composition‐dependent phase‐segregation is revealed and investigated for the first time during the phase‐pure mixed‐cation perovskites CsxFA1−xPbI3. The present findings demonstrate that suppressing phase‐segregation of mixed‐cation perovskites by meticulous composition engineering is significant for further development of efficient photovoltaics.
Abstract
For the current medical block chain, the access rights of electronic medical records and agent encryption are mainly controlled by permission contract. The way of protecting electronic ...medical records realizes the sharing of medical data, but neglects the management and protection of user identity. In this paper, this article studies the privacy protection technology of the blockchain, combined with the stealth address and zero-knowledge proof technology, and proposes a plan to weigh anonymity and security to protect the privacy of users in the medical blockchain.
Sensory perception is dramatically influenced by the context. Models of contextual neural surround effects in vision have mostly accounted for Primary Visual Cortex (V1) data, via nonlinear ...computations such as divisive normalization. However, surround effects are not well understood within a hierarchy, for neurons with more complex stimulus selectivity beyond V1. We utilized feedforward deep convolutional neural networks and developed a gradient-based technique to visualize the most suppressive and excitatory surround. We found that deep neural networks exhibited a key signature of surround effects in V1, highlighting center stimuli that visually stand out from the surround and suppressing responses when the surround stimulus is similar to the center. We found that in some neurons, especially in late layers, when the center stimulus was altered, the most suppressive surround surprisingly can follow the change. Through the visualization approach, we generalized previous understanding of surround effects to more complex stimuli, in ways that have not been revealed in visual cortices. In contrast, the suppression based on center surround similarity was not observed in an untrained network. We identified further successes and mismatches of the feedforward CNNs to the biology. Our results provide a testable hypothesis of surround effects in higher visual cortices, and the visualization approach could be adopted in future biological experimental designs.
Currently, many clinical trials have shown that inulin-type fructans (ITF) supplementation is associated with glycemic control; nevertheless, the results are inconclusive. The aim of this ...meta-analysis of randomized controlled trials was to assess the effects of ITF supplementation on glycemic control.
PubMed, EMBASE and the Cochrane Library were searched for eligible articles up to March 6, 2019. A random-effects model was used to analyze the pooled results, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was applied to assess the quality of evidence. The dose-response model was used to recommend the daily dose and duration for ITF supplementation.
Thirty-three trials involving 1346 participants were included. Overall, ITF supplementation could significantly reduce concentrations of fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), fasting insulin (FINS) and homeostasis model assessment-insulin resistance (HOMA-IR). In the prediabetes and type 2 diabetes (T2DM) population, a more significant reduction in FBG weighted mean difference (WMD): - 0.60 mmol/l; 95% CI - 0.71, - 0.48 mmol/l; high rate, HbA1c (WMD: - 0.58%; 95% CI - 0.83, - 0.32%; high rate), FINS (WMD: - 1.75 µU/ml; 95% CI - 2.87, - 0.63 µU/ml; low rate), and HOMA-IR (WMD: - 0.69; 95% CI - 1.10, - 0.28; low rate) were observed, and ITF supplementation with a daily dose of 10 g for a duration of 6 weeks and longer was recommended. Moreover, subgroup analyses suggested that the effects of glycemic control were significantly influenced by the sex of the subjects and the type and the method of intake of ITF.
Our analyses confirmed that these four main glycemic indicators were significantly reduced by ITF supplementation, particularly in the prediabetes and T2DM population. Evidence supports that reasonable administration of ITF supplementation may have potential clinical value as an adjuvant therapy for prediabetes and T2DM management. Trial registration The trial was registered at PROSPERO as CRD42018115875 on November 23, 2018.
The immunotherapy efficacy on pancreatic cancer remains unsatisfactory. Therefore, it is still necessary to further clarify the pancreatic immune cell infiltration and search for immune-related ...prognostic indicators. We analyzed the 135 pancreatic cancer patients' data retrieved from the TCGA database for the immune cell infiltration, tumor microenvironment score and the correlation of the immune cells, followed by identification of prognostic immune clusters and genes clusters. The R language was used for the immune score calculation, and immune cells proportion related survival differences identification. The function of immune cells was verified through datasets in the GEO database and in vivo experiments. The results showed that M0 Macrophages had negative relations to CD8 + T cells and immune scores. There were differences in median survival in ICI clusters, gene clusters, and immune score groups (p < 0.05). M0 macrophages accounted for more than 9.8%, indicating a poor prognosis, while T cells accounted for more than 9.2%, indicating a good prognosis. In vivo results showed that M0 macrophages promote pancreatic cancer growth. Elimination of M0 macrophages may be a hopeful strategy against pancreatic cancer.
Coastal acoustic tomography (CAT) is a remote sensing technique that utilizes acoustic methodologies to measure the dynamic characteristics of the ocean in expansive marine domains. This approach ...leverages the speed of sound propagation to derive vital ocean parameters such as temperature and salinity by inversely estimating the acoustic ray speed during its traversal through the aquatic medium. Concurrently, analyzing the speed of different acoustic waves in their round-trip propagation enables the inverse estimation of dynamic hydrographic features, including flow velocity and directional attributes. An accurate forecasting of inversion answers in CAT rapidly contributes to a comprehensive analysis of the evolving ocean environment and its inherent characteristics. Graph neural network (GNN) is a new network architecture with strong spatial modeling and extraordinary generalization. We proposed a novel method: employing GraphSAGE to predict inversion answers in OAT, using experimental datasets collected at the Huangcai Reservoir for prediction. The results show an average error 0.01% for sound speed prediction and 0.29% for temperature predictions along each station pairwise. This adequately fulfills the real-time and exigent requirements for practical deployment.
Although sugar-sweetened beverage consumption has become an important and widespread concern, there are few studies on the association between sugar-sweetened beverage consumption frequency and ...muscle strength in Chinese adolescents. The objective of this study was to analyze the association between sugar-sweetened beverage consumption frequency and muscle strength in Chinese adolescents.
A stratified whole-group sampling method was used to survey 25,893 adolescents aged 13-15 years old in China for sugar-sweetened beverage consumption frequency and muscle strength for grip strength and standing long jump. The subjects' basic information, body mass index (BMI), and covariates were investigated. The association between sugar-sweetened beverage consumption frequency and muscle strength was analyzed by multivariate logisitc regression analysis.
The proportions of Chinese adolescents who consumed sugar-sweetened beverage ≥ 3 times/week, 1-2 times/week, and < 1 time/week were 12.23%, 52.79%, and 34.98%, respectively. The differences in sugar-sweetened beverage consumption frequency were statistically significant when compared across gender, parental education, duration of physical activity, snacks, and mode of commuting to school (χ
values = 228.570, 51.422, 275.552, 3165.656, 10.988, P < 0.01). Logistic regression analysis showed that overall Chinese adolescents with sugary drinks 1-2 times/week (OR = 1.207, 95% CI:1.132-1.287) and sugary drinks ≥ 3 times/week (OR = 1.771, 95% CI:1.611-1.947) were associated with lower muscle strength compared to sugary drinks < 1 time/week showed a positive association (P < 0.01). The same trend was found for boys and girls.
Chinese adolescents' sugar-sweetened beverage consumption is common, and high-frequency sugar-sweetened beverage consumption is associated with lower muscle strength. In the future, we should control the use of sugar-sweetened beverages and increase muscular strength training in Chinese adolescents to promote healthy growth.
Polymer membranes have been widely used in guided tissue regeneration (GTR) and guided bone regeneration (GBR). In this review, various commercially available membranes are described. Much attention ...is paid to the recent development of biodegradable polymers applied in GTR and GBR, and the important issues of biodegradable polymeric membranes, including their classification, latest experimental research and clinical applications, as well as their main challenges are addressed. Herein, natural polymers, synthetic polymers and their blends are all introduced. Pure polymer membranes are biodegradable and biocompatible, but they lack special properties such as antibacterial properties, osteoconductivity, and thus polymer membranes loaded with functional materials such as antibacterial agents and growth factors show many more advantages and have also been introduced in this review. Despite there still being complaints about polymer membranes, such as their low mechanical properties, uncontrollable degradation speed and some other drawbacks, these problems will undoubtedly be conquered and biodegradable polymers will have more applications in GTR and GBR.
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