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Netizens all over the world can search malicious websites by malicious long-tail keywords on search engines, but malicious websites are strictly prohibited by law in most countries, so the construction of short text classification models for detecting malicious long-tail keywords has become a key research topic of Natural Language Processing (NLP). Most of the short text classification models are for English, with the widespread use of Chinese, there is an urgent need to develop Chinese short text classification models to help Chinese search engines detect malicious long-tail keywords. Considering that malicious long-tail keywords often evade detection by using homophones that have the same pinyin, pinyin is added to solve the homophonic typos problem of Chinese short text. Considering the data sparsity problem of malicious long-tail keywords, pinyin and radicals are added to obtain more abundant features. Since there is no publicly available pre-trained pinyin and radical embedding models, the embedding vectors of Chinese words, radical and pinyin are trained through Word2Vec, and 492,345 individual word embedding vectors, 207,995 individual radical embedding vectors and 402,071 individual pinyin embedding vectors are obtained. In addition, the positional encoding and part-of-speech coefficient are added to them, and the TF-IDF and MI values are added to reflect the word frequency weight and the different importance of the same word in different documents. Then, two parallel co-attention networks are used to fuse features of words, pinyin, and radicals, BIGRU is used to extract temporal features, and CNN is used to extract local features. Multi-group comparative experiment results on two short text benchmark datasets and pornographic and gambling long-tail keywords show that the proposed model outperforms the state-of-the-art text classification model. [ABSTRACT FROM AUTHOR]

Nanofilms that can fast permeate solvents and accurately sieve molecules are of significant importance for separation. A promising strategy is to align the inner cavities of macrocycles into the channels within nanofilms, and control the channel size by selecting the macrocycles. However, the channels outside the macrocycles are ignored. Here, we prepare nanofilms with hydrophobic channels (cyclodextrin inner cavity) and hydrophilic channels (cyclodextrin outer space) through interfacial polymerization of azobenzene-4,4′-dicarbonyl dichloride and amino-functionalized β-cyclodextrin. By utilizing the significant geometric changes caused by the photoisomerization of azobenzene, nanofilms with adjustable hydrophilic channel sizes were obtained. Our nanofilms have high permeability to polar and non-polar solvents, and can distinguish molecules with almost the same molecular weight but different shapes. This work expands the development of next-generation nanofilms generated through interfacial polymerization by incorporating rational molecular design. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) present significant risks to human health owing to their carcinogenic, teratogenic, and mutagenic properties. The contamination of surface water with PAHs via runoff has become a prominent source of water pollution. While the capacity of bioretention systems to remove PAHs from runoff is recognized, the dynamics of PAH migration and degradation in these systems are not well-understood. This study aims to explain the migration and fate of PAHs in bioretention systems through a series of experiments and model simulations. This study constructed bioretention systems with three different media types and found that these systems achieved PAH load reductions exceeding 92%. Notably, naphthalene (NAP), fluoranthene (FLT), and pyrene (PYR) tended to accumulate in the media's upper layer, at depths of 10 to 40 cm. To further analyze the migration and fate of PAHs during multi-site rainfall events and across prolonged operation, we applied the HYDRUS-1D model under three distinct scenarios. The findings of this study indicated that NAP degraded in 40 d, whereas FLT and PYR showed incomplete degradation after 120 d. During continuous rainfall events, there was no clear pattern of PAH accumulation; however, FLT and PYR persisted in the bioretention systems. The combination of experimental and simulation findings highlights the inevitable accumulation of PAHs during extended use of bioretention systems. This research provides a theoretical basis for improving operational efficiency, advancing PAH degradation in bioretention systems, and reducing their toxicity. [ABSTRACT FROM AUTHOR]

Rain gardens play a key role in urban non-point source pollution control. The drainage type affects the infiltration processes of runoff pollutants. The soil properties and microbial community structures were studied to reveal the stability of the ecosystem in rain gardens with different drainage types under long-term operation. The results showed that the soil water content and total organic carbon in the drained rain gardens were always higher than that of the infiltrated ones. With the increase in running time, the contents of heavy metals in rain gardens showed significant accumulation phenomena, especially the contents of Zn and Pb in drained rain gardens were higher than that in infiltrated ones. The accumulation of pollutants resulted in lower microbial diversity in drained rain gardens than in infiltrated rain gardens, but the microbial community structures were the same in all rain gardens. The effects of drainage type on microbial community evolution were not significant, only the accumulation of heavy metals led to changes in the abundance of dominant microorganisms. There were differences in the soil environment of rain gardens with different drainage types. The long-term operation of rain gardens led to fluctuations in the soil ecosystem, while the internal micro-ecosystems of the drained rain gardens were in unstable states. [ABSTRACT FROM AUTHOR]

The composition statistics of gynecological microscopic images play an important role in the diagnosis and treatment of gynecology. However, current methods mainly rely on manual analysis of microscopic images, which is time-consuming and subjective. Therefore, the purpose of this paper is to develop a gynecological microscopic image component statistics method based on optical medical equipment and medical intelligent system to improve the accuracy and efficiency of gynecological diagnosis. The method of combining optical medical equipment and medical intelligent system is used to realize the automatic analysis of gynecological microscopic images. A large number of gynecological microscopic image samples were collected, and image processing technology was used to preprocess the images. Then computer vision algorithm and machine learning method are used to extract and classify the image features. Finally, the new gynecological microscopic images were analyzed statistically according to the trained model. The experimental results show that the method presented in this paper has a good effect on the composition statistics of gynecological microscopic images. Compared with the traditional manual analysis method, this method can analyze gynecological microscopic images more quickly and accurately, and provide effective diagnostic results. [ABSTRACT FROM AUTHOR]

The rapid development of China's new urbanization has created favorable conditions for economic growth and social development. Urbanization includes population urbanization and land urbanization, among which land urbanization leads to land ecological security problems. At present, there is a lack of comprehensive understanding of land ecological security in China's new urbanization construction. This paper aims to fill the gap by systematically combing relevant literature on the connotation, status, and governance of land ecological security in China's new urbanization. Literature review shows that China's land ecological security is still at a low level, and the new urbanization construction has significant impacts on land ecological security. Land contamination is the most critical factor threatening land ecological security, and there are differences in the levels of land contamination and types of pollutants in different new urbanization construction forms. According to an example of land ecological security governance with enterprises as the main body and multiple subjects cooperating, the governance of land ecological security needs to integrate a variety of different subjects to coordinate governance. Future research directions should focus on the construction of land ecological security assessment index system, development of land contamination multi-level control technology, and construction of multi-subject collaborative governance model with "government-enterprise-social organization-residents." [ABSTRACT FROM AUTHOR]

Palmprint biometrics has a broad application prospect owing to non-intrusiveness, ease of image acquisition and stable textural pattern. Hand-crafted approaches are vulnerable to non-ideal palmprint images caused by uneven illumination, motion blur and noise contamination. Many researchers have designed excellent texture descriptors or/and advanced image pre-processing algorithms. Nevertheless, they are highly targeted at some specific data, less adaptable to the emerging data. In this paper, a semi-pretrained contactless palmprint recognition deep network is developed to achieve high accuracy and robustness. Semi-CPRN is composed of underlying network structure from ResNet-152 and the proposed assistant layers dedicated to high-performance palmprint recognition. The well-designed assistant layers enhance convolutional neural network to steadily extract the real palmprint features even from the degraded images without being deceived by the degradation factors. Besides, to better carry out the research on palmprint recognition in the open environment, we established a new contactless database HIT-NIST-V1 under natural scene. The comparative experiments on CASIA, IITD, PolyU3D/2D, Tongji and HIT-NIST-V1 illustrate that Semi-CPRN is comparable and superior to previously published state-of-the-art approaches. Simultaneously, CNN-based palmprint biometrics methods show significant robustness to motion blur, Gaussian noise, and salt and pepper noise. [ABSTRACT FROM AUTHOR]

Finger-vein has been used for automatic personal recognition systems for over a decade. Its size and characteristics against presentation attacks make it suitable for various commercial and governmental applications. As with other biometric traits, the majority of finger-vein recognition methods employ hand-crafted feature for image classification. Lately, there are some convolutional neural network (CNN) models are designed for finger-vein identification and verification. Whereas, the CNN-based approaches tend to set up increasing layers and more parameters, which incur equipment memory issue and algorithm execution speed issue. Besides, many researchers have made great efforts to enhance hand-crafted feature-based method by using image enhancement algorithms. Hence, it is significant to explore high-performance finger-vein recognition without image enhancement in deep learning world. In this work, two different dimension issues are investigated: lightweight CNN model, the effect of image enhancement on finger-vein biometrics in deep feature space. Transfer learning plays an important role in extracting informative and representative features by information transfer from the pre-trained network to a novice via fine-tuning. The experimental results on four benchmark databases HKPU, FV-USM, SDUMLA and UTFVP demonstrate the proposed lightweight model 'LightFVN' outperforms the existing published competition winners. Furthermore, image enhancement turns out not to be essential for CNN-based finger-vein biometrics. [ABSTRACT FROM AUTHOR]

The potential for toxic elements to contaminate soil has been extensively studied. Therefore, the development of cost-effective methods and materials to prevent toxic element residues in the soil from entering the food chain is of great significance. Industrial and agricultural wastes such as wood vinegar (WV), sodium humate (NaHA) and biochar (BC) were used as raw materials in this study. HA was obtained by acidizing NaHA with WV and then loaded onto BC, which successfully prepared a highly efficient modification agent for nickel-contaminated soil, namely biochar-humic acid material (BC-HA). The characteristics and parameters of BC-HA were obtained by FTIR, SEM, EDS, BET and XPS. The chemisorption of Ni(II) ions by BC-HA conforms to the quasi-second-order kinetic model. Ni(II) ions are distributed on the heterogeneous surface of BC-HA by multimolecular layer adsorption, which accords with the Freundlich isotherm model. WV promotes better binding of HA and BC by introducing more active sites, thus increasing the adsorption capacity of Ni(II) ions on BC-HA. Ni(II) ions in soil are anchored to BC-HA by physical and chemical adsorption, electrostatic interaction, ion exchange and synergy. [ABSTRACT FROM AUTHOR]

Novel thermoplastic polyurethane (TPU)/multi walled carbon nanotubes (MWCNTs) conductive nanocomposites were fabricated by direct solution compounding method for volatile organic compounds (VOCs) sensors applications. The results of field emission scanning electron microscopy (FESEM) and electrical conductivity test showed that MWCNTs formed ideal conductive networks in TPU matrix. The volume conductivity of TPU/MWCNTs nanocomposites increased from 10-12 to 10-4S/mm, and the percolation value was 4.76 wt%. The size parameters of MWCNTs did not show obvious effects on the formation of conductive networks based on our comparative investigation. XRD and FTIR tests showed that MWCNTs enhanced the short range ordered structure in amorphous region of TPU due to the physical entanglement. The characteristic stretching of TPU showed no obvious change because of weak chemical interaction between MWCNTs and TPU. Moreover, MWCNTs effectively enhanced the thermal stability of the nanocomposites, as verified by TG analysis. The gas sensing property tests showed that the gas sensing response of TPU/MWCNTs nanocomposites mainly came from the resistance changes due to the disconnection of conductive networks, as a result of VOCs adsorption-swelling effects. The prepared nanocomposites showed superior selectivity, especially to benzene vapor when compared with formaldehyde and other gases. The parameters and contents of MWCNTs have a certain influence on the gas sensing response speed and recovery ability of the nanocomposites. In addition, the prepared TPU/MWCNTs nanocomposites displayed excellent repeatability and fast response to the change of electrical resistance (in seconds) after cyclic exposure to VOCs and pure dry air. [ABSTRACT FROM AUTHOR]

Six bioretention filter columns were designed to study the effects of the bioretention system on surface runoff reduction through rainfall simulation water distribution experiments, and the relationship between the physicochemical properties of contaminated fillers and microbial community structure was analyzed. Results show that (1) the water volume and load reduction effect of traditional bioretention soil media (BSM) + 5% water treatment residue (WTR) was better than that of traditional bioretention soil media; (2) soil moisture content (SMC), carbon, nitrogen, phosphorus, Cd, and Cu increased after the water distribution test, while the change of Zn in the filter columns varied; (3) species richness decreased after the experiment. In terms of microbial community structure, the top 10 dominant phyla did not change. At the genus level, Arthrobacter replaced Sphingomonas as the most abundant flora after the experiment; (4) the effects of the physicochemical properties of contaminated fillers on microbial community structure in terms of pH were not clear, but total organic carbon(TOC), total phosphorus(TP), and SMC greatly influenced the microbial community structure, while the influence of heavy metals on the relative abundance at the phylum and genus levels was not uniform. [ABSTRACT FROM AUTHOR]

Correction to: I Scientific Reports i https://doi.org/10.1038/s41598-023-32502-x, published online 11 April 2023 The original version of this Article contained errors in Figure 7, where panel ( B a b ) was a duplication of panel ( B b b ). Graph: Figure 7EDS spectrum of (a) BC, BC-NaHA, BC-HA; (b) BC + Ni, BC-NaHA + Ni, BC-HA + Ni. [Extracted from the article]

Virtual machine placement has great potential to significantly improve the efficiency of resource utilization in a cloud center. Focusing on CPU and memory resource, this paper presents SOWO—a discrete particle swarm optimization-based workload optimization approach to minimize the number of active physical machines in virtual machine placement. The experiment results show the usability and superiority of SOWO. Compared with the OpenStack native scheduler, SOWO decreases the physical machine consumption by at least 50% and increases the memory utilization of physical machine by more than two times. [ABSTRACT FROM AUTHOR]

Landscape pathology is a research approach that can provide validation of the effectiveness of regional controls of forest disease at a landscape scale. In this paper, we analyzed the effects of stand features, management approaches, and geographical locations on poplar canker disease incidence (DI) and disease severity index (DSI) of individual trees at a 10 km × 10 km mesoscale landscape in Qingfeng County, China. DI varied significantly with stand age, tree densities, and the degree of canopy closure. DI in stands younger than 4 years old was significantly lower than that in the stands over 6 years old and reached the highest value at a stand age of 8-10 years. Overall, DI was positively correlated with stand age, stand density, and the degree of canopy closure. DI was significantly lower in agro-forest stand patches than in other three patch types, i.e. isolated patch, pure stand patch, and mixed stand patch. Poplar plantations distributed around and near to villages exhibited significantly higher DI mainly due to human activities and herbivores. Fragmentation or connectivity in this mesoscale landscape seemed not impact disease occurrence. DSI was not significantly correlated with stand density, but varied significantly with tree varieties and trees ages. DSI was highest in stands of 10-12 year trees for all poplar varieties we studied here. Plantation density and plantation age were thus critical factors in determining DI and DSI. A logistic predictive model of disease occurrence was developed for the study area, considering varieties, age, height, density, canopy cover, stand types, patch types, management status, and stand geographical locations. Our study here shows that adjustment of stand density by thinning at different plantation ages is an effective approach controlling the occurrence canker disease in short-rotation poplar plantations at the landscape scale. [ABSTRACT FROM AUTHOR]

Site-directed mutagenesis is a very important technique in molecular biological researches. We have developed a new method for long distance multiple-site plasmid mutation by one-step PCR using non-overlap primers. These primers were carefully designed and contained desired mutations in the middle of the primers flanked with 18-25 bp of correct sequence. One pair of the primers was able to generate a short megaprimer. Decreases in the concentrations of these primers increased efficiency of the multiple-site plasmid mutation. All of the mutant PCRs were performed at a common annealing temperature at 55 °C. This method could be widely used in all multiple-site plasmid mutations. [ABSTRACT FROM AUTHOR]

Clinical reports have found that with the improvement of treatment, most septic patients are able to survive the severe systemic inflammatory response and to enter the immunoparalysis stage. Considering that immunoparalysis leads to numerous deaths of clinical sepsis patients, alleviation of the occurrence and development of immunoparalysis has become a top priority in the treatment of sepsis. In our study, we investigate the effects of oroxylin A on sepsis in cecal ligation and puncture (CLP) mice. We find that the 60 h + 84 h (30 mg/kg) injection scheme of oroxylin A induce the production of pro-inflammatory factors, and further significantly improves the survival of CLP mice during the middle or late stages of sepsis. Mechanistically, C/EBP-homologous protein (CHOP) is upregulated and plays anti-inflammatory roles to facilitate the development of immunoparalysis in CLP mice. Oroxylin A induces the transcription of E3 ligase F-box only protein 15 gene (fbxo15), and activated FBXO15 protein binds to CHOP and further mediates the degradation of CHOP through the proteasome pathway, which eventually relieves the immunoparalysis of CLP mice. Taken together, these findings suggest oroxylin A relieves the immunoparalysis of CLP mice by degrading CHOP through interacting with FBXO15. [ABSTRACT FROM AUTHOR]

A new thiophene acetylene, named 2,2-dimethyl-4-[5′-(prop-1-ynyl)-2,2′-bithiophen-5-yl]-1,3-dioxolane ( 1), was isolated from the roots of Echinops spinosus, and the structure was elucidated on the basis of oneand two-dimensional NMR (including H, C NMR, DEPT, H-H COSY, HSQC, and HMBC). [ABSTRACT FROM AUTHOR]