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Artificial intelligence is dramatically reshaping scientific research and is coming to play an essential role in scientific and technological development by enhancing and accelerating discovery across multiple fields. This book dives into the interplay between artificial intelligence and the quantum sciences; the outcome of a collaborative effort from world-leading experts. After presenting the key concepts and foundations of machine learning, a subfield of artificial intelligence, its applications in quantum chemistry and physics are presented in an accessible way, enabling readers to engage with emerging literature on machine learning in science. By examining its state-of-the-art applications, readers will discover how machine learning is being applied within their own field and appreciate its broader impact on science and technology. This book is accessible to undergraduates and more advanced readers from physics, chemistry, engineering, and computer science. Online resources include Jupyter notebooks to expand and develop upon key topics introduced in the book.
Numerical investigations of convective flow and heat transfer in two different engineering applications, namely cross-corrugated channels for heat exchangers and rib-roughened channels for gas turbine blade cooling, using wall-modeled large eddy simulations (LES), are presented in this chapter. Mesh resolution requirements for LES, subgrid model dependence, and heat transfer and friction factor characteristics are investigated and compared with previously published experimental data. The LES computations form a coherent suite of monotonically behaving predictions, with all aspects of the results converging toward the predictions obtained on the finest grids. Various subgrid and Reynolds-averaged Navier–Stokes equations (RANS) models are compared to account for their reliability and efficiency in the prediction of hydraulic and thermal performances in the presence of complicated flow physics. Results indicate that subgrid models such as wall-adapting local eddy viscosity model (WALE) and localized dynamic kinetic energy model (LDKM) provide the most accurate results, within 201b of Nusselt number and Darcy’s friction factor, compared to selected RANS models, which presents up to 3501b deviation from experimental data. The conclusion is that both LES and RANS have their strengths and weaknesses, and the choice between them depends on the specific application requirements and available computational resources.
The safety of human-collaborative operations with robots depends on monitoring the external torque of the robot, in which there are toque sensor-based and torque sensor-free methods. Economically, the classic method for estimating joint external torque is the first-order momentum observer (MOB) based on a physic model without torque sensors. However, uncertainties in the dynamic model, which encompasses parameters identification error and joint friction, affect the torque estimation accuracy. To address this issue, this paper proposes using the backpropagation neural network (BPNN) method to estimate joint external torque without the delicate physical model by utilizing the powerful machine learning ability to handle the uncertainties of the MOB method and improve the accuracy of torque estimation. Using data obtained from the torque sensor to train the BPNN to build up a digital torque model, the trained BPNN can perceive force in practical applications without relying on the torque sensor. In the end, by contrast to the classic first-order MOB, the result demonstrates that BPNN achieves higher estimation accuracy compared to the MOB.
Substantial changes resulting from the interaction of environmental and dietary factors contribute to an increased risk of obesity, while their specific associations with obesity remain unclear. Identify inflammation-related dietary patterns (DPs) and explore their associations with obesity among urbanized Tibetan adults under significant environmental and dietary changes.Totally, 1826 subjects from the suburbs of Golmud City were enrolled in an open cohort study, of which 514 were followed up. Height, weight, and waist circumference were used to define overweight and obesity. DPs were derived using reduced rank regression with 41 food groups as predictors and hs-CRP and prognostic nutritional index as inflammatory response variables. Altitude was classified as high or ultra-high. Two DPs were extracted. DP-1 was characterized by having high consumptions of sugar-sweetened beverages, savory snacks, and poultry, and a low intake of tsamba. DP-2 had high intakes of poultry, pork, animal offal, and fruits, and a low intake of butter tea. Participants in the highest tertiles (T3) of DPs had increased risks of overweight and obesity (DP-1: OR=1.37, 95% CI: 1.07, 1.77; DP-2: OR=1.48, 95% CI: 1.18, 1.85) than those in the lowest tertiles (T1). Participants in T3 of DP-2 had an increased risk of central obesity (OR=2.25, 95% CI: 1.49, 3.39) than those in T1. The positive association of DP-1 with overweight and obesity was only significant at high altitudes, while no similar effect was observed for DP-2. Inflammation-related DPs were associated with increased risks of overweight and/or obesity.
Loess, a geologic record of dust, is an optimal archive for exploring paleoclimate and the paleo-dust path from source to sink. The dust path for the Songnen Plain, NE China, during the last glacial period has not been established. To address this, 63 surface sediment samples from the Northeast China Sandy Lands, i.e., Onqin Daga Sandy Land (OD), Horqin Sandy Land (HQ), Hulun Buir Sandy Land (HL), and Songnen Sandy Land (SN), and six samples from the last glacial loess in the Harbin area were collected for elemental geochemical analysis of the <10 μm fraction to quantitatively reconstruct the dust pathway using a frequentist model. The results show that these sandy lands have a distinct geochemical composition due to a control from markedly different provenances. The quantitative results indicate that the dust contribution of the southwestern SN to the Harbin loess is as high as 50.4–77.2%, followed by the OD and HQ (3.3–34.8%), the northwestern SN (0–36.8%), and the HL (0–8%). Notably, the dust contribution to the Harbin loess began to change considerably after ~46–41 ka BP, with a significant increase from 1.1% to 41.2% from the northwestern direction. Some ecological safety strategies are proposed to address dust pollution in the Harbin area.
There is a lack of longitudinal data on the relationship between upward social comparison on social network sites (SNSs) and depression and its underlying mechanisms. Therefore, this study aimed to examine the relationship between upward social comparison on social network sites and depression and analyze the mediating effects of self-concept clarity and self-esteem in this relationship. We employed a two-wave longitudinal design among 1179 Chinese middle school students. The results indicated that : upward social comparison on SNSs predicted middle school students’ depression; Self-concept clarity and self-esteem sequentially mediated the relationship between upward social comparison on SNSs and middle school students’ subsequent depression. These results suggested that three types of interventions could be effectively used to decrease the risk of depression among middle school students.
The presence of dispersed-phase droplets can result in a notable increase in a system's drag. However, our understanding of the mechanism underlying this phenomenon remains limited. In this study, we use three-dimensional direct numerical simulations with a modified multi-marker volume-of-fluid method to investigate liquid–liquid two-phase turbulence in a Taylor–Couette geometry. The dispersed phase has the same density and viscosity as the continuous phase. The Reynolds number $Re\equiv r_i\omega _i d/\nu$ is fixed at 5200, the volume fraction of the dispersed phase is up to $40\,\%$, and the Weber number $We\equiv \rho u^2_\tau d/\sigma$ is approximately 8. It is found that the increase in the system's drag originates from the contribution of interfacial tension. Specifically, droplets experience significant deformation and stretching in the streamwise direction due to shear near the inner cylinder. Consequently, the rear end of the droplets lags behind the fore head. This causes opposing interfacial tension effects on the fore head and rear end of the droplets. For the fore head of the droplets, the effect of interfacial tension appears to act against the flow direction. For the rear end, the effect appears to act in the flow direction. The increase in the system's drag is attributed primarily to the effect of interfacial tension on the fore head of the droplets which leads to the hindering effect of the droplets on the surrounding continuous phase. This hindering effect disrupts the formation of high-speed streaks, favouring the formation of low-speed ones, which are generally associated with higher viscous stress and drag of the system. This study provides new insights into the mechanism of drag enhancement reported in our previous experiments.
Modern fluvial sediments provide important information about source-to-sink process and regional tectono-magmatic events in the source area, but many factors, e.g., chemical weathering, sedimentary cycles and source-rock types, can interfere with the establishment of the source-sink system. The Lalin River (LR) and the Jilin Songhua River (JSR) are two important tributaries of the Songhua River in the Songnen Plain in NE China. They have similar flow direction, topography and identical climate backgrounds, but have notably different parent-rock types in the headwater, which provides an opportunity to explore the influencing factors of river sediment composition. To this end, the point bar sediments in the two rivers were sampled for an analysis of geochemistry (including element and Sr-Nd isotopic ratios), heavy mineral and detrital zircon U-Pb dating. The results are indicative of the fact that the two rivers have the similar geochemical composition (e.g., elements and Sr isotopes) as well as chemical weathering (CIA = 51.41–57.60, CIW = 59.68–66.11, PIA = 51.95–60.23, WIP = 56.00–65.47, Rb/Sr = 0.38–0.42) and recycling (SiO2/Al2O3 = 5.79 and 5.03, ICV = 1.0 and 1.2, CIA/WIP = 0.81–1.03) characteristics, showing a major control of climate on the low-level weathering and recycling of the river sediments. However, there are significant differences in the detrital zircon U-Pb age (a significant Mesozoic age peak for the LR but an additional Precambrian peak for the JSR), Nd isotope ratio (−6.2812–8.5830 and −8.1149–10.2411 for the LR and the JSR, respectively) and to a certain extent heavy mineral composition (e.g., for the < 63 μm fraction, a dominance of hornblende and magnetite in the LR, but haematite-limonite in the JSR) in the two river sediments, indicating that source rocks largely control the composition of the river sediments. Some of the major tectono-magmatic events (e.g., crustal growth and cratonisation of the North China Craton, closure of the Paleo-Asian Ocean, subduction and rollback of the Paleo-Pacific plate) occurring in the eastern Songnen Plain are well documented in the JSR sediments but not in the LR, the difference of which is largely regulated by the source rocks in the source area.
This study examined children at the onset of tic disorder (tics for less than 9 months: NT group), a population on which little research exists. Here, we investigate relationships between the baseline shape and volume of subcortical nuclei, diagnosis, and tic symptom outcomes.
Methods
187 children were assessed at baseline and a 12-month follow-up: 88 with NT, 60 tic-free healthy controls (HC), and 39 with chronic tic disorder/Tourette syndrome (TS), using T1-weighted MRI and total tic scores (TTS) from the Yale Global Tic Severity Scale to evaluate symptom change. Subcortical surface maps were generated using FreeSurfer-initialized large deformation diffeomorphic metric mapping. Linear regression models correlated baseline structural shapes with follow-up TTS while accounting for covariates, with relationships mapped onto structure surfaces.
Results
We found that the NT group had a larger right hippocampus compared to HC. Surface maps illustrate distinct patterns of inward deformation in the putamen and outward deformation in the thalamus for NT compared to controls. We also found patterns of outward deformation in almost all studied structures when comparing the TS group to controls. The NT group also showed consistent outward deformation compared to TS in the caudate, accumbens, putamen, and thalamus. Subsequent analyses including clinical symptoms revealed that a larger pallidum and thalamus at baseline correlated with less improvement of tic symptoms at follow-up.
Conclusion
These observations constitute some of the first prognostic biomarkers for tic disorders and suggest that these subregional shape and volume differences may be associated with the outcome of tic disorders.
Foodborne diseases are ongoing and significant public health concerns. This study analysed data obtained from the Foodborne Outbreaks Surveillance System of Wenzhou to comprehensively summarise the characteristics of foodborne outbreaks from 2012 to 2022. A total of 198 outbreaks were reported, resulting in 2,216 cases, 208 hospitalisations, and eight deaths over 11 years. The findings suggested that foodborne outbreaks were more prevalent in the third quarter, with most cases occurring in households (30.8%). Outbreaks were primarily associated with aquatic products (17.7%) as sources of contamination. The primary transmission pathways were accidental ingestion (20.2%) and multi-pathway transmission (12.1%). Microbiological aetiologies (46.0%), including Vibrio parahaemolyticus, Salmonella ssp., and Staphylococcus aureus, were identified as the main causes of foodborne outbreaks. Furthermore, mushroom toxins (75.0%), poisonous animals (12.5%), and poisonous plants (12.5%) were responsible for deaths from accidental ingestion. This study identified crucial settings and aetiologies that require the attention of both individuals and governments, thereby enabling the development of effective preventive measures to mitigate foodborne outbreaks, particularly in coastal cities.
This study aims to evaluate the impact of low-carbohydrate diet, balanced dietary guidance and pharmacotherapy on weight loss among individuals with overweight or obesity over a period of 3 months. The study involves 339 individuals with overweight or obesity and received weight loss treatment at the Department of Clinical Nutrition at the Second Affiliated Hospital of Zhejiang University, School of Medicine, between 1 January 2020 and 31 December 2023. The primary outcome is the percentage weight loss. Among the studied patients, the majority chose low-carbohydrate diet as their primary treatment (168 (49·56 %)), followed by balanced dietary guidance (139 (41·00 %)) and pharmacotherapy (32 (9·44 %)). The total percentage weight loss for patients who were followed up for 1 month, 2 months and 3 months was 4·98 (3·04, 6·29) %, 7·93 (5·42, 7·93) % and 10·71 (7·74, 13·83) %, respectively. Multivariable logistic regression analysis identified low-carbohydrate diet as an independent factor associated with percentage weight loss of ≥ 3 % and ≥ 5 % at 1 month (OR = 0·461, P < 0·05; OR = 0·349, P < 0·001). The results showed that a low-carbohydrate diet was an effective weight loss strategy in the short term. However, its long-term effects were comparable to those observed with balanced dietary guidance and pharmacotherapy.
The AIMTB rapid test assay is an emerging test, which adopted a fluorescence immunochromatographic assay to measure interferon-γ (IFN-γ) production following stimulation of effector memory T cells in whole blood by mycobacterial proteins. The aim of this article was to explore the ability of AIMTB rapid test assay in detecting Mycobacterium tuberculosis (MTB) infection compared with the widely applied QuantiFERON-TB Gold Plus (QFT-Plus) test among rural doctors in China. In total, 511 participants were included in the survey. The concordance between the QFT-Plus test and the AIMTB rapid test assay was 94.47% with a Cohen’s kappa coefficient (κ) of 0.84 (95% CI, 0.79–0.90). Improved concordance between the two tests was observed in males and in participants with 26 or more years of service as rural doctors. The quantitative values of the QFT-Plus test was higher in individuals with a result of QFT-Plus-/AIMTB+ as compared to those with a result of QFT-Plus-/AIMTB- (p < 0.001). Overall, our study found that there was an excellent consistency between the AIMTB rapid test assay and the QFT-Plus test in a Chinese population. As the AIMTB rapid test assay is fast and easy to operate, it has the potential to improve latent tuberculosis infection testing and treatment at the community level in resource-limited settings.
Growing evidence indicates a link between diet and depression risk. We aimed to examine the association between an inflammatory diet index and depression utilising extensive data from UK biobank cohort. The energy-adjusted dietary inflammation index (E-DII) was calculated to quantify the potential of daily diet, with twenty-seven food parameters utilised. The E-DII scores were classified into two categories (low v. high) based on median value. To mitigate bias and ensure comparability of participant characteristics, propensity score matching was employed. To ascertain the robustness of these associations, sensitivity analyses were conducted. Subgroup analyses were performed to evaluate the consistency of these associations within different subpopulations. Totally, 152 853 participants entered the primary analyses with a mean age of 56·11 (sd 7·98) years. Employing both univariate and multivariate logistic regression models, adjustments were made for varying degrees of confounding factors (socio-demographics, lifestyle factors, common chronic medical conditions including type 2 diabetes and hypertension). Results consistently revealed a noteworthy positive correlation between E-DII and depression. In the context of propensity score matching, participants displaying higher E-DII scores exhibited an increased likelihood of experiencing incident depression (OR = 1·12, 95 % CI: 1·05, 1·19; P = 0·000316). Subgroup analysis results demonstrated variations in these associations across diverse subpopulations. The E-value for the point-estimate OR calculated from the propensity score matching dataset was 1·48. Excluding individuals diagnosed with type 2 diabetes or hypertension, the findings consistently aligned with the positive association in the primary analysis. These findings suggested that consumption of a diet with higher pro-inflammatory potential might associated with an increase of future depression risk.
The tension distribution problem of cable-driven parallel robots is inevitable in real-time control. Currently, iterative algorithms or geometric algorithms are commonly used to solve this problem. Iterative algorithms are difficult to improve in real-time performance, and the tension obtained by geometric algorithms may not be continuous. In this paper, a novel tension distribution method for four-cable, 3-DOF cable-driven parallel robots is proposed based on the wave equation. The tension calculated by this method is continuous and differentiable, without the need for iterative computation or geometric centroid calculations, thus exhibiting good real-time performance. Furthermore, the feasibility and rationality of this algorithm are theoretically proven. Finally, the real-time performance and continuity of cable tension are analyzed through a specific numerical example.
Although numerous neuroimaging studies have depicted neural alterations in individuals with obsessive–compulsive disorder (OCD), a psychiatric disorder characterized by intrusive cognitions and repetitive behaviors, the molecular mechanisms connecting brain structural changes and gene expression remain poorly understood.
Methods
This study combined the Allen Human Brain Atlas dataset with neuroimaging data from the Meta-Analysis (ENIGMA) consortium and independent cohorts. Later, partial least squares regression and enrichment analysis were performed to probe the correlation between transcription and cortical thickness variation among adults with OCD.
Results
The cortical map of case-control differences in cortical thickness was spatially correlated with cortical expression of a weighted combination of genes enriched for neurobiologically relevant ontology terms preferentially expressed across different cell types and cortical layers. These genes were specifically expressed in brain tissue, spanning all cortical developmental stages. Protein–protein interaction analysis revealed that these genes coded a network of proteins encompassing various highly interactive hubs.
Conclusions
The study findings bridge the gap between neural structure and transcriptome data in OCD, fostering an integrative understanding of the potential biological mechanisms.
This study aims to explore the concept of future orientation, which encompasses individuals’ thoughts about the future, goal-setting, planning, response to challenges and behavioural adjustments in evolving situations. Often viewed as a psychological resource, future orientation is believed to be developed from psychological resilience. The study investigates the curvilinear relationship between childhood maltreatment and future orientation while examining the moderating effects of genotype.
Methods
A total of 14,675 Chinese adults self-reported their experiences of childhood maltreatment and their future orientation. The influence of genetic polymorphism was evaluated through genome-wide interaction studies (GWIS; genome-wide association study [GWAS] using gene × environment interaction) and a candidate genes approach.
Results
Both GWAS and candidate genes analyses consistently indicated that rs4498771 and its linked single-nucleotide polymorphisms, located in the intergenic area surrounding CSF3R, significantly interacted with early trauma to influence future orientation. Nonlinear regression analyses identified a quadratic or cubic association between future orientation and childhood maltreatment across some genotypes. Specifically, as levels of childhood maltreatment increased, future orientation declined for all genotypes. However, upon reaching a certain threshold, future orientation exhibited a rebound in individuals with specific genotypes.
Conclusions
The findings suggest that individuals with certain genotypes exhibit greater resilience to childhood maltreatment. Based on these results, we propose a new threshold model of stress-related growth.
The discovery that blazars dominate the extra-galactic $\gamma$-ray sky is a triumph in the Fermi era. However, the exact location of $\gamma$-ray emission region still remains in debate. Low-synchrotron-peaked blazars (LSPs) are estimated to produce high-energy radiation through the external Compton process, thus their emission regions are closely related to the external photon fields. We employed the seed factor approach proposed by Georganopoulos et al. It directly matches the observed seed factor of each LSP with the characteristic seed factors of external photon fields to locate the $\gamma$-ray emission region. A sample of 1 138 LSPs with peak frequencies and peak luminosities was adopted to plot a histogram distribution of observed seed factors. We also collected some spectral energy distributions (SEDs) of historical flare states to investigate the variation of $\gamma$-ray emission region. Those SEDs were fitted by both quadratic and cubic functions using the Markov-chain Monte Carlo method. Furthermore, we derived some physical parameters of blazars and compared them with the constraint of internal $\gamma\gamma$-absorption. We find that dusty torus dominates the soft photon fields of LSPs and most $\gamma$-ray emission regions of LSPs are located at 1–10 pc. The soft photon fields could also transition from dusty torus to broad line region and cosmic microwave background in different flare states. Our results suggest that the cubic function is better than the quadratic function to fit the SEDs.
The Chinese Loess Plateau (CLP), recognized as the world's largest loess plateau, has been a subject of ongoing debate regarding the continuity of its sedimentary loess sequence due to its intricate depositional environment. In this study, we conducted dating on a 9.8-m-long Malan loess core obtained from the Sanmen Gorge in the southern CLP using optically stimulated luminescence (OSL). The OSL dates indicate loess deposition between 52.4 and 11.3 ka, with no apparent hiatus on a millennial scale, and a sedimentation rate (SR) exhibiting six distinct episodes. Additionally, a comprehensive review of 613 OSL ages from 18 sections at 14 sites across the CLP was conducted. The results reveal loess deposition at most sites shows no apparent hiatus on a millennial scale over the past 60 ka, except for two specific locations. High SR episodes during Marine Isotope Stage (MIS) 3 across the CLP were attributed to heightened dust emissions from the source region and an enhanced dust deposition efficiency, while MIS 2 deposits were influenced by an intensified East Asian winter monsoon. Low SR episodes during MIS 1 at most sites were likely associated with reduced atmospheric transportation and pedogenesis. Spatially heterogeneous SR variations across the CLP might be influenced by local depositional environments.