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Background: Due to the influence of external wind speed and their flight speed, the droplets sprayed by the plant protection Unmanned Aerial Vehicles (UAV) have serious drift and volatilization. Objective: The aim was to study the atomization characteristics of the fan-shaped atomizing nozzle of UAV under different inlet pressures and in different internal cavity diameters. Methods: Firstly, the Realizable k-ε turbulence model, DPM discrete phase model, and TAB breakup model are used to make a numerical simulation of the spray process of the nozzle. Then, the SIMPLE algorithm is used to obtain the droplet size distribution diagram of the nozzle atomization field. At last, the related test methods are used to study its atomization performance and the changes of atomization angle and droplet velocity under different inlet pressures and in different internal cavity diameters; the distribution of droplet size is also discussed. Results: The research results show that when the diameter of the internal cavity is the same, as the inlet pressure increases, the spray cone angle of the nozzle and the droplet velocity at the same distance from the nozzle increase. As the distance from the nozzle increases, the droplet velocity decreases gradually, the droplet size distribution moves to the direction of small diameter, and the droplets in the anti-drift droplet size area increase. Under the same inlet pressure, as the diameter of the internal cavity increases, the spray cone angle first increases and then decreases, and the droplet velocity at the same distance from the nozzle increases. As the distance from the nozzle increases, the droplet velocity decreases gradually, the droplet size distribution moves to the direction of large diameter, and the size of the large droplets increases, thereby, not meeting the condition of anti-drift volatilization effect. Conclusion: Under the parameters set in this study, i.e., when the inlet pressure was 0.6 MPa, and the internal cavity diameter was 2 mm, the best atomization result was obtained.

To solve the problems of cold start and data sparseness existing in traditional collaborative filtering recommendation algorithm, a collaborative filtering recommendation algorithm based on user attributes and item scoring is proposed. Firstly, we improve the credibility of user similarity and explore the potential interests of users, a new user rating similarity calculation method is constructed by introducing confidence, item popularity, and Pearson weighting. Secondly, we construct a user attribute similarity measurement method by introducing cultural distance, age attribute similarity, and user label similarity. Finally, user rating similarity and user attribute similarity are weighted to form a new similarity measurement model. Through simulation comparison between the collaborative filtering recommendation algorithm and the traditional recommendation algorithm, our results show that the collaborative filtering recommendation algorithm can effectively improve the accuracy of recommendations and the diversity of results and effectively alleviate the problem of data sparseness.

Evidence has demonstrated that Daphnetin has antiangiogenesis activity, indicating it might be a new multi-targeted medication for cancer therapy. Here, we aimed to reveal Daphnetin role in hepatocellular carcinoma (HCC) progression and the underlying mechanism. Huh7 and SK-HEP-1, two human HCC cell lines were used in this study. MTT （3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide）, colony formation, flow cytometry, and tumor-bearing experiments were applied to evaluate the effects of different concentrations of Daphnetin on cell viability, apoptosis, cell cycle, and in vivo tumor formation, respectively. Real-time PCR （Polymerase Chain Reaction）and western blotting were applied to measure the mRNA and protein levels of β-catenin. We observed that Daphnetin inhibited cell viability and tumorigenesis, promoted cell apoptosis, and induced a G1 phase arrest in a dose-dependent manner in both Huh7 and SK-HEP-1 cells, which were rescued by SKL2001, an activator of the Wnt/β-catenin signaling. Taken together, this study reveals that Daphnetin exerts an antitumor role in HCC through the inactivation of Wnt/β-catenin signaling.

Late Stenian to Tonian stratum of the Xihe and Jinxian groups, the Sangwon system, the Penglai Group, the Tumen Group, and the Huaibei and Langan groups located at the eastern margin of the North China Craton provide an excellent record of changes in sediment provenance related to the amalgamation and dispersal of Rodinia and therefore the paleogeographic position of the craton. To decipher their protosource changes over time, we evaluated 7510 U-Pb and 963 Lu-Hf analyses from 92 samples across the entire eastern North China Craton, of which 1746 U-Pb and 415 Lu-Hf analyses from 18 samples are newly reported here. The detrital zircon results indicate two stratigraphic intervals with internally consistent lithostratigraphy, event stratigraphy, biostratigraphy, depositional age, and detrital zircon age patterns: the late Stenian to early Tonian strata and the late Tonian strata, of which the former mainly consists of the Mesoproterozoic detrital zircons with juvenile Hf isotopic features and the latter’s detritus chiefly derived from the Neoarchean to late Paleoproterozoic basement of the North China Craton. In consideration of the paleomagnetic and geochronological data from the coeval strata in other cratons, the Mesoproterozoic detrital zircons of the late Stenian to early Tonian strata are interpreted to be derived from the Musgrave Province in central Australia during the Rodinia amalgamation, and the transition to the autochthonic protosources in the late Tonian possibly indicated the breakup of the North China Craton and North Australian Craton connection.

The direct growth of graphene at low temperature on the desired dielectric substrate by plasma en-hanced chemical vapor deposition (PECVD) is significant for its electronic and optoelectronic ap-plications. However, due...

To improve prognosis of cancer patients and determine the integrative value for analysis of disease-free survival prediction, a clinic investigation was performed involving with 146 non-small cell lung cancer (NSCLC) patients (83 men and 73 women; mean age: 60.24 years ± 8.637) with a history of surgery. Their computed tomography (CT) radiomics, clinical records, and tumor immune features were firstly obtained and analyzed in this study. Histology and immunohistochemistry were also performed to establish a multimodal nomogram through the fitting model and cross-validation. Finally, Z test and decision curve analysis (DCA) were performed to evaluate and compare the accuracy and difference of each model. In all, seven radiomics features were selected to construct the radiomics score model. The clinicopathological and immunological factors model, including T stage, N stage, microvascular invasion, smoking quantity, family history of cancer, and immunophenotyping. The C-index of the comprehensive nomogram model on the training set and test set was 0.8766 and 0.8426 respectively, which was better than that of the clinicopathological-radiomics model (Z test, P =0.041

The brain functional parcellation based on functional magnetic resonance imaging (fMRI) data is a research hotspot in the field of brain science. However, due to the large dimension and low signal-to-noise ratio of fMRI data, the majority of current parcellation methods are ill-equipped to handle it, exhibiting weak search capabilities and poor functional parcellation structures. To address the issues, this paper provides a novel brain functional parcellation method based on particle swarm optimization (PSO) with dynamic nonlinear inertia weight and population-topology selection strategy (called DPPSO). In DPPSO, a functional correlation matrix derived from preprocessed fMRI data is mapped into a low-dimensional space with spectral mapping. Then, DPPSO employs an enhanced PSO to search cluster centers that are encoded as particle positions, where a dynamic nonlinear inertia weight is adopted to balance the global search and the local search, and a population-topology selection strategy for individual historical optimal position in the speed update formula is employed to increase the diversity of particle swarms. Finally, a functional parcellation result is obtained by mapping the cluster labels of low-dimensional data to the corresponding voxels. The experimental results on real fMRI data demonstrate that DPPSO has a stronger search capability and achieves a more better functional parcellation in terms of spatial structures and functional consistency.

This paper describes a 3D finite element (FE) based method to calculate the proximity losses for magnetic components in power conversion system. The proximity loss is the main concern of copper loss which causes ac losses in the winding. The FE model is built based on the definitions of the geometries, meshes, materials, electric circuits, boundary conditions, load conditions, as well as the characteristics of the wire. The total proximity loss is the sum of the power losses of each element calculated with the power loss density function using the obtained nodal flux densities via finite element analysis (FEA) at the given load condition. Owing to a detailed model with all the geometric parameters and thus the flux leakage and end-winding effects can be considered, this FEA approach can predict the flux density more accurately. In addition, non-sinusoidal current is analyzed to calculate the actual power loss in current distortion condition. Experimental tests have been implemented to validate the method. The approach is capable of calculating the energy consumption in power converter for efficiency approvement and energy management.

Figure S1: Cathodoluminescence images of all the analyzed detrital zircon grains from the Penglai Group in this study. Figure S2: Cathodoluminescence images of all the analyzed detrital zircon grains from the Tumen Group in this study. Figure S3: Cathodoluminescence images of all the analyzed detrital zircon grains from the Huaibei Group in this study. Figure S4: Probability density plots of single sample of the Penglai Group in this study. Figure S5: Probability density plots of single sample of the Tumen Group in this study. Figure S6: Probability density plots of single sample of the Huaibei Group in this study. Figure S7: εHf(t) versus age for detrital zircon of the individual sample in this study. Table S1: LA-ICPMS detrital zircon U–Pb dating results. Table S2: MC-LA-ICPMS detrital zircon Lu-Hf isotopic results. Table S3: Detrital zircon U-Pb age summary of the samples from the late Mesoproterozoic to early Neoproterozoic strta in the eastern North China Craton.

The Wuhe Complex in the Bengbu area of the Jiao–Liao–Ji Belt, southeast North China Craton, contains garnet-bearing mafic granulites that have undergone high-pressure (HP) and ultrahigh-temperature (UHT) metamorphism. These granulites also experienced partial melting and occur as lenses within marbles. Petrographic observations and quantitative phase equilibria modeling reveal clockwise P–T paths, involving an inferred HP stage followed by decompressional, medium-pressure, granulite-facies metamorphism and subsequent cooling. The HP assemblage of garnet + clinopyroxene + plagioclase + K-feldspar ± amphibole ± quartz ± rutile indicates P–T conditions of 840–980 °C and 12–17 kbar. This was followed by post-peak, near-isothermal decompression with the development of orthopyroxene + clinopyroxene + plagioclase + K-feldspar + garnet + amphibole + ilmenite at 850–960 °C and 7–10 kbar, resulting in the development of orthopyroxene rims on resorbed garnet. Pyroxene and ternary feldspar thermometry yielded high temperatures of ~1150 °C and 1055–1087 °C at 10 kbar, respectively, which constrain the minimum crystallization temperatures of the igneous protoliths. The host and lamellae of the pyroxene and ternary feldspar are relict magmatic minerals/textures that survived metamorphism due to the silica-undersaturated bulk-rock conditions. Zr-in-rutile thermometry yielded temperatures of ~935 °C and 800 °C, with the former being consistent with the predicted peak metamorphic temperatures. Small amounts of melts (up to 5%) were generated during decompression of the Bengbu mafic granulites. The generated partial melts were mainly (quartz) monzonite at 900–920 °C, and the silica contents of the melts were controlled by the quartz stability field in P–T pseudosections. The partial melts were enriched in Na and strongly depleted in Fe–Mg at the peak pressure of ~14 kbar and 920 °C, and later evolved to Fe–Mg-rich and high-K compositions during decompression. The melt compositions in the studied rocks are similar when the pressures reached ~9 kbar. The modal proportion of amphibole increased as the melt H2O content decreased at lower pressures, indicating that the limited H2O remaining in the host rocks was consumed to produce amphibole. U–Pb geochronology of zircon containing inclusions of clinopyroxene, plagioclase, and apatite constrains the timing of metamorphism to 1930–1840 Ma, as is the case for HP granulites from Shandong, Liaoning, and southern Jilin in the central and northeastern Jiao–Liao–Ji Belt. The Wuhe HP–UHT mafic granulites were ultimately sourced from upwelling asthenosphere-derived magma at ~2.1 Ga, which intruded and crystallized at shallower depths. The igneous protoliths were then buried to middle–lower crustal levels and experienced HP–UHT granulite-facies metamorphism and partial melting at 1.95–1.90 Ga related to continental subduction and overthickening. The HP–UHT mafic granulites were rapidly exhumed at ~1.85 Ga and generated small volumes of (quartz) monzonite during decompression. The newly discovered Paleoproterozoic HP–UHT mafic granulites associated with partial melting suggest that the continent materials were deeply subducted to the lower crustal levels and that additional heating was not involved. The finding of the HP–UHT granulites, together with the widespread distributions of the granulite-facies metamorphic rocks and the determination of the clockwise P–T–t paths, reveal that the Paleoproterozoic Jiao–Liao–Ji orogenic belt extends at least 1000 km, starting from southern Jilin, passing through the southeastern Liaoning and Jiaobei terranes, and elongating to the Bengbu area in Anhui.

Statherian through Tonian strata of the Langshan–Zha’ertai–Bayan Obo–Huade rift zone (LZBH) at the northern margin of the North China Craton provide an excellent record of changes in sediment provenance related to the supercontinent dispersal and amalgamation. During the late Paleoproterozoic to early Neoproterozoic, the LZBH developed over the Yinshan Block and was flanked by the Khondalite Belt to the south, the Trans–North China Orogen and Yanliao rift zone to the east, ultimately preserving a >7000-m-sequence of fluvial, marginal marine, and offshore marine sediments. In order to decipher the influence of these tectonic features on sediment delivery to the area, we evaluated 4955 U-Pb and 1616 Lu-Hf analyses from 66 samples across the entire LZBH, of which 1002 U-Pb and 271 Lu-Hf analyses from 12 samples are newly reported herein. The detrital zircon results indicate three stratigraphic intervals with internally consistent age peaks: (1) Changcheng to lower Jixian system (Statherian–lower Calymmian), (2) upper Jixian system (upper Calymmian), and (3) Qingbaikou system (Tonian). Statistical analysis of the detrital zircon results reveals two distinct changes in sediment provenance. The first transition, between the lower and upper Calymmian, reflects a provenance change from the basement of the Yinshan Block and the Khondalite Belt to a mixed signature, indicating derivation from both basement and Statherian rift-related magmatic products. Such a transition implies establishment of east–west drainage systems traversing the Paleoproterozoic Trans–North China Orogen caused by continued rifting since Statherian and pre-magmatic uplift during breakup of the North China Craton from the Columbia supercontinent. The second transition is indicated by the presence of Mesoproterozoic detrital zircons with juvenile Hf isotopic features since Tonian time and the up-section and northward increase of Mesoproterozoic detrital zircons. Their provenance is interpreted to be the Fennoscandian shield by a pancontinental drainage system related to aggregation of the Rodinia supercontinent. Thus, the detrital zircon spectra in the LZBH document the transition from initial unroofing of local uplifted basement of the Yinshan Block and Khondalite Belt to the distant Yanliao rift zone, then to the more distant Fennoscandian shield.

Objective To explore the correlation between radiomic features and the pathology of pure ground-glass opacities (pGGOs), we established a radiomics model for predicting the pathological subtypes of minimally invasive adenocarcinoma (MIA) and precursor lesions. Methods: CT images of 1521 patients with lung adenocarcinoma or precursor lesions appearing as pGGOs on CT in our hospital (The Third Affiliated Hospital of Sun Yat-sen University) from January 2015 to March 2021 were analyzed retrospectively and selected based on inclusion and exclusion criteria. pGGOs were divided into an atypical adenomatous hyperplasia (AAH)/adenocarcinoma in situ (AIS) group and an MIA group. Radiomic features were extracted from the original and preprocessed images of the region of interest. ANOVA and least absolute shrinkage and selection operator feature selection algorithm were used for feature selection. Logistic regression algorithm was used to construct radiomics prediction model. Receiver operating characteristic curves were used to evaluate the classification efficiency. Results 129 pGGOs were included. 2107 radiomic features were extracted from each region of interest. 18 radiomic features were eventually selected for model construction. The area under the curve of the radiomics model was 0.884 [95% confidence interval (CI), 0.818–0.949] in the training set and 0.872 (95% CI, 0.756–0.988) in the test set, with a sensitivity of 72.73%, specificity of 88.24% and accuracy of 79.47%. The decision curve indicated that the model had a high net benefit rate. Conclusion The prediction model for pathological subtypes of MIA and precursor lesions in pGGOs demonstrated a high diagnostic accuracy. Advances in knowledge: We focused on lesions appearing as pGGOs on CT and revealed the differences in radiomic features between MIA and precursor lesions. We constructed a radiomics prediction model and improved the diagnostic accuracy for the pathology of MIA and precursor lesions.

As a key heat-dissipating and electrical interconnecting component in high-temperature power modules, die-attach and substrate-attach layers play an important role in effectively reducing the thermal resistance and improving the long-term reliability. Traditional substrate-attach materials limit the high-temperature applications of packaging modules due to their high thermal resistance and high-temperature reliability. To solve the above deficiency, a copper foam-silver composite was proposed in this paper, which was prepared by mixing copper foam solid skeleton with micron silver paste. According to the results of thermogravimetric analysis (TGA) of silver paste, the preheating process was determined and sintered at 270°C and 10MPa. The influence of different preparation technology on the quality of sintered joint was investigated. The morphology characteristics and distribution of sintered silver in the copper foam were observed by scanning electron microscope (SEM). The results show that the sintered silver of group C samples can be uniformly filled into the solid skeleton of copper foam, and the densification degree is high, without cracks, delamination, and holes. The shear strength can reach 55MPa.

Microwave Assisted Ignition (MAI) is a promising technology to optimize the lean combustion characteristics of internal combustion engines. This research investigated the effects of microwave pulse waveform and delay time on energy coupling and ignition enhancement by using a power diagnostic with high time-resolution. The pulse width ranged from 80 to 200 μs and the corresponding peak power was adjusted between 1000 and 400 W to keep the incident energy of microwave pulse constant. Results showed that a high power and short width pulse waveform was conducive to the microwave energy absorption. The coupled energy generally decreased with delay time. There was a significant ignition enhancement with only 6-7 mJ energy coupled into the flame kernel, which was approximately 1/5 of total spark energy. Moreover, the ignition enhancement was well correlated with the coupled energy, suggesting that ignition enhancement was determined by coupled energy via electron collision reactions. Finally, the main influencing factor of coupled energy was the energy coupling pattern which changed from none-coupling to saturated coupling. A high pulse power and short delay time facilitated this change. This study revealed the saturated coupling pattern independent of waveform and delay time, which is caused by a stable electron number density due to the cut-off effect.

Due to the complexity and uncertainty of customer demand behavior, it was often difficult to obtain satisfactory recommendation results by using the existing online commodity recommendation systems. Therefore, a network commodity intelligent recommendation model based on feature selection and deep belief network was proposed. Based on the basic structure and function of the existing recommendation systems, this paper expounded the interaction process between customers, e-commerce platforms, enterprises, and the recommendation system. By analyzing the internal relationship between customer demand and commodity recommendation, the relationship model between customer demand and commodity recommendation was established. After analyzing the characteristics of customers’ demand for goods, a data mining method was used to classify the characteristics of customers’ demand behavior, and a feature selection method based on deep belief network (DBN) was proposed to obtain the main information conducive to commodity recommendation. Finally, an e-commerce commodity recommendation algorithm based on feature selection and deep belief network was proposed. The experimental results showed that the network commodity recommendation model proposed in this paper can not only provide customers with satisfactory recommendation results but also has better performance than other traditional recommendation models. The recommendation model proposed in this paper can support different e-commerce website recommendation systems.

Graphene oxide (GO) has superior molecular sieving abilities due to its unimpeded two-dimensional (2D) nano-channels and nacre-like lamellar structure. However, it remains a huge challenge to fully exploit its unmatched features to construct a GO-based membrane on a large scale for excellent screening performance. Here, we display a facile, ultrafast and environmentally friendly strategy to design an ultrathin (graphene/graphene oxide@polyetherimide) GR/GO@PEI composite membrane under the collective effects of a hydrophilic PEI molecular-bridge and an ordered GR/GO laminar structure. Excitingly, this composite membrane presents extraordinary structural stability, even when transferred to any given substrate, regardless of its chemical components, structure, or specification. Furthermore, this membrane shows high permeance of up to 191 L m−2 h−1 bar−1 and over 99% rejection of Congo red, far superior to the majority of GO-based separation membranes reported so far. In addition, it can withstand several types of physical damage and chemical corrosion, as well as being further able to realize the purification of actual, complex, multi-component, domestic sewage. This work will open the door to developing scalable 2D lamellar membranes with ultrafast and precise separation channels for practical water purification.

The Langshan area is located in the northeastern margin of the Alxa block, which is the westernmost part of the North China Craton (NCC). The Langshan Group has been divided into four formations, of which the 1st formation deposited in the period of 1.83–1.66 Ga, the 2nd and 3rd formations formed between 1.16 Ga and 0.80 Ga and the 4th formation deposited after 1.17 Ga, whereas part of the previously believed Neoarchean Alxa “Group” deposited in the period of 1.65 Ga and 1.37 Ga. U-Pb ages of detrital zircons from the Langshan Group and the early Mesoproterozoic Alxa “Group” yielded age peaks of 2.51–2.48 Ga, 2.38–2.33 Ga, 1.89–1.81 Ga, 1.79–1.62 Ga, 1.58–1.56, 1.36–1.31 and 1.18–1.17 Ga. The late Neoarchean to middle Paleoproterozoic detrital zircons are mainly documented in the 1st formation and are derived from the ca. 2.5 Ga Guyang, Xi Ulanbulang and Beidashan granitoids, ca.1.9 Ga Xuwujia, Halaqin igneous rocks and the S-type granites, and the ca. 2.32 Ga Bayanwulashan orthogneisses. The late Paleoproterozoic (1.79–1.62 Ga) detrital zircons with negative eHf(t) values in the Alxa “Group” are interpreted to be sourced from the coeval rift-related granitic plutons and volcanic rocks in the northern NCC. On the other way, the late Paleoproterozoic to Mesoproterozoic detrital zircons with positive eHf(t) values from the upper Langshan Group probably sourced from the Fennoscandian shield of the Baltica craton. Based on the similarities in the stratigraphic sequence and detrital zircon age patterns of the Changcheng, Jixian and Qingbaikou systems, we infer that the Alxa Block was still an integrated part of the NCC in the early Neoproterozoic time.

In the southern zone of the Paleoproterozoic Jiao-Liao-Ji Belt (JLJB), North China Craton (NCC), abundant granitic leucosomes are widespread within migmatites as irregular layers, lenses, and blocks. They are parallel to or as cross-cut foliations in the host rocks on various scales, and show distinct evidence of migmatization in the formation of these centimeter- to decimeter-scale segregations. The migmatites extend at least 1100 km in length, spreading over the whole JLJB, from the Ji’an Group in south Jilin, through the South Liaohe Group in Liaodong Peninsula, to the Jingshan Group in Jiaodong Peninsula, rather than as sporadic outcrops limited to the Jiaobei Terrane as reported in previous studies. The granitic leucosomes are comprised mainly of quartz, K-feldspar, and antiperthitic plagioclase (albite), with secondary minerals of garnet, biotite, zircon, etc. They are enriched in SiO 2 (74.65–75.54 wt%), Al 2 O 3 (13.25–14.87 wt%), and K 2 O + Na 2 O (8.19–8.95 wt%), but have a lower TiO 2 + Fe 2 O 3 + FeO + MgO + MnO content (0.42–1.34 wt%). The major element components are similar to those of granitic leucosomes of pelitic granulites in typical orogenic belts around the world. A combined study of whole-rock geochemistry, mineral inclusions, cathodoluminescence (CL) images, and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb dates of zircons revealed the nature and timing of partial melting of the host pelitic granulites. All dated anatectic zircons from various granitic leucosomes display magmatic zones with distinct cores and rims, and contain mineral inclusions of Qtz + Kfs + Ab ± Ap in both domains. Both the cores and rims exhibit unusually high U and Th contents, and anomalously low Th/U ratios (