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Aiming at the sealing failure of a water quality monitoring system in a low-temperature environment, a double rubber O-ring sealing structure was designed, and its sealing performance at low temperatures was studied. Finite element software ANSYS constructed the sealing structure, and the change of sealing performance of rubber O-ring in the process of standard temperature installation and low temperature was studied by a two-dimensional axisymmetric model. The results show that the equivalent strain and stress of the sealing structure show an increasing trend during the installation process. With the effect of the medium pressure, the maximum contact stress of the rubber seal ring increases from 2.6285 MPa at 20 ℃ to 2.6657 MPa at 0 ℃. The contact width decreases gradually with the decrease in temperature. With the initial compression rate increase, the maximum contact stress increases significantly. The simulation results show that the double-layer rubber O-ring structure still has good sealing performance at low temperatures.

In the 1990s, China’s northeast including Liaoning, Jilin, and Heilongjiang provinces, the bastion of state-owned heavy industry, underwent a massive state-owned enterprise (SOE) reform engineered by Deng Xiaoping as part of the “Reform and Opening-up Policy,” which resulted in large-scale SOE bankruptcies and some 30 million blue-collar workers being laid off. 20 years after the reform, China’s northeast, once among the most urbanized regions in the country, has effectively become China’s “Rust Belt.” This article examines the cinematic representations of China’s Rust Belt, specifically in China’s northeast, arguing that cinema plays a crucial role in both capturing and interrogating the emergence of new urban spaces and urban subjects amidst the spatial and ideological reorientations of the reform era. It also investigates the ways in which cinematic representations, through a shifting “system of symbols,” mediate the contradictions in the production of urban spaces, cultural norms, and social identities.

Emotion Recognition in Conversations (ERC) has considerable prospects for developing empathetic machines. For multimodal ERC, it is vital to understand context and fuse modality information in conversations. Recent graph-based fusion methods generally aggregate multimodal information by exploring unimodal and cross-modal interactions in a graph. However, they accumulate redundant information at each layer, limiting the context understanding between modalities. In this paper, we propose a novel Multimodal Dynamic Fusion Network (MM-DFN) to recognize emotions by fully understanding multimodal conversational context. Specifically, we design a new graph-based dynamic fusion module to fuse multimodal contextual features in a conversation. The module reduces redundancy and enhances complementarity between modalities by capturing the dynamics of contextual information in different semantic spaces. Extensive experiments on two public benchmark datasets demonstrate the effectiveness and superiority of MM-DFN., Comment: Accepted by ICASSP 2022

Changes in microbial communities and drivers of their composition in different restoration approaches are largely unexplored. The aim of this study was to evaluate the effects of different ecosystem restoration approaches on bacterial community diversity and whether changes in soil physico-chemical properties are driving bacterial community dynamics. Soil samples were collected from restored lands covered with grass, coniferous forest, young conifer-broadleaf forest, mature conifer-broadleaf forest, and natural broad-leaved forest and bare land. The bacterial community was determined by 16S rDNA sequencing while soil physico-chemical properties were determined using standard methodologies. We found that the physico-chemical properties of degraded red soil were improved following re-vegetation. Soil bulk density and soil pH decreased while soil moisture content increased in restored sites compared to bare land. Soil organic carbon, total P, K, N, and available P and K contents were the highest in conifer-broadleaved forest soil. Soil bacterial community diversity significantly increased following restoration of degraded landscape, with Chloroflexi, Proteobacteria, Firmicutes, Cyanobacteria, WPS-2, Acidobacteria, Verrucomicrobia, Actinobacteria, and Bacteroidetes being dominant. The major bacteria phyla were positively correlated with soil chemical properties, but negatively correlated with soil physical properties and pH. It can be concluded that favorable changes in soil physico-chemical properties following restoration mediate bacterial community diversity, depending on vegetation cover types used to restore the degraded land.

Pogonatherum crinitum is a promising lead (Pb) hyperaccumulator due to its high Pb tolerance and accumulation ability. However, the mechanisms that support Pb accumulation and tolerance in P. crinitum are not yet clearly understood. An indoor hydroponic experiment was conducted by cultivating P. crinitum seedlings exposed to intermittent Pb stress for 60 days, divided into four stages (T1, T2, T3 and T4), with a 15-day duration per stage. The following concentrations of Pb were used: 0, 500, 0, 500 mg·l-1 and 0, 1000, 0, 1000 mg·l-1 ). Antioxidant enzyme activity, Pb concentration and subcellular distribution of Pb were measured at each of the above stages. The results showed that superoxide dismutase (SOD) activity in shoots, and SOD, peroxidase (POD) and malondialdehyde (MDA) activity in shoots and roots significantly increased from T1 (no Pb stress) to T2 (Pb stress) in both 500 mg·l-1 and 1000 mg·l-1 treatments; however, no significant difference was noted between stages T3 (no Pb stress) and T4 (Pb stress). There was no obvious effect of Pb stress on catalase (CAT) activity in shoots and roots among different stages. The Pb concentration in shoots was up to 5090.90 mg·kg-1 and 7573.57 mg·kg-1 , and the bioconcentration factor (BFC) was 10.18 and 7.57 for the 500 mg·l-1 and 1000 mg·l-1 treatments, respectively, which confirmed the Pb hyperaccumulator characteristics of P. crinitum. For plants under Pb stress, most of the Pb was fixed in the cell walls, with a smaller amount in leaves and root vacuoles. Both SOD and POD scavenging of reactive oxygen radicals and fixing and compartmentalisation of Pb in the cell wall might play important roles in detoxification of P. crinitum seedlings in response to Pb stress. There was no phased response of P. crinitum to intermittent Pb stress and the physiological response to Pb stress may be contiguous.

Background Under natural conditions, soil nutrients are heterogeneously distributed, and plants have developed adaptation strategies to efficiently forage patchily distributed nutrient. Most previous studies examined either patch strength or patch size separately and focused mainly on root morphological plasticity (increased root proliferation in nutrient-rich patch), thus the effects of both patch strength and size on morphological and physiological plasticity are not well understood. In this study, we examined the foraging strategy of Neyraudia reynaudiana (Kunth) Keng ex Hithc, a pioneer grass colonizing degraded sites, with respect to patch strength and size in heterogeneously distributed phosphorus (P), and how foraging patchily distributed P affects total plant biomass production. Plants were grown in sand-culture pots divided into ½, ¼, 1/6 compartments and full size and supplied with 0 + 0/30, 0 + 7.5/30 and 7.5 + 0/30 mg P/kg dry soil as KH2PO4 or 0 + 15/15, 0 + 18.5/ 18.5, 7.5 + 15/15 mg kg − 1 in the homogenous treatment. The first amount was the P concentration in the central region, and that the second amount was the P concentration in the outer parts of the pot. Results After 3 months of growth under experimental conditions, significantly (p Conclusion The result demonstrates that root morphological and physiological plasticity are important adaptive strategies for foraging patchily distributed P and the former is largely determined by patch strength and size. The results also establish that foraging patchily distributed P resulted in increased total plant biomass production compared to homogeneous P distribution.

Pogonatherum crinitum is a promising lead (Pb) hyperaccumulator; however, the effects of Pb contamination on P. crinitum rhizosphere soil enzymatic activities and microbial composition remain largely unexplored. Thus, an indoor experiment was conducted by cultivating P. crinitum seedlings and exposing them to four Pb concentrations (0, 1,000, 2000 and 3000 mg/kg Pb). Protease, urease, acid phosphatase and invertase activities were determined using standard methods while soil bacterial composition was determined by 16 S rDNA sequencing. The results showed that rhizosphere soil acid phosphatase activity significantly increased with increasing Pb concentration, while urease activity was significantly greater in rhizosphere soil contaminated with 1000 and 2000 mg/kg than in the control. There was a clear shift in bacterial composition during phytoremediation by P. crinitum. Compared to the control, Bacteroidetes was more abundant in all Pb-contaminated soils, Actinobacteria was more abundant in 1000 mg/kg Pb-treated soil, and Firmicutes was more abundant in 3000 mg/kg Pb-treated soil. Positive correlations were observed between dominant bacterial phyla and soil enzyme activities. Metabolic pathways, such as ABC transporter, quinine reductase, and ATP-binding protein were significantly increased in rhizosphere soil bacteria with Pb contamination. In conclusion, Pb contamination differentially influenced the activities of rhizosphere soil enzymes, specifically increasing acid phosphatase and urease activities, and alters the dominance of soil bacteria through up-regulation of genes related to some metabolic pathways. The strong correlations between dominant bacterial phyla and enzymatic activities suggest synergetic effects on the growth of P. crinitum during Pb contamination.

Additional file 1. Supplementary material.

Pogonatherum crinitum (Thunb.) Kunth is a lead (Pb) tolerant, perennial grass and a hyperaccumulator of Pb based on field surveys and greenhouse experiments. However, only few attempts have been made to understand the response mechanisms of P. crinitum to high Pb concentrations. In this study, we measured leaf chlorophyll fluorescence, antioxidative enzyme activities, organic acid contents, and Pb concentrations of P. crinitum grown in soil containing four concentrations of Pb (0, 500, 1000, and 2500 mg kg−1, respectively) for a period of three months. Our results indicated that chlorophyll a and total chlorophyll concentrations were significantly lower in Pb treated plants compared to the control, while chlorophyll b concentrations were not significantly different from those in the control. Furthermore, Pb stress increased the photosystem II (PSII) maximum photochemical efficiency. The activities of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD), and organic acid contents such as oxalic and malic acids in roots were significantly increased by Pb treatments. Furthermore, the malondialdehyde content in leaves was significantly reduced by higher Pb concentration treatments. The Pb concentration was significantly increased by Pb treatments, and transfer coefficient exceeded 1 (Pb2500 treatment). These results suggest that increase in light use efficiency, scavenging reactive oxygen by strengthening anti-oxidative enzyme activity, and complexation of Pb with organic acids may play important roles in alleviating the toxicity of Pb in P. crinitum.

In this study, we subjected the root systems of eight Eucalyptus hybrids currently cultivated in southern China to heterogeneous phosphorus stress to provide a scientific basis for the selection of a highly phosphorus-efficient Eucalyptus variety. When the ability of these hybrids to locate phosphorus under different experimental conditions (phosphorus supply in a homogeneous or heterogeneous manner vs. no phosphorus supply) was compared, the main growth characteristics of Eucalyptus, such as plant height, diameter, dry mass, and phosphorus content, significantly improved when the phosphorus supply was increased from no phosphorus or heterogeneous phosphorus (half of the phosphorus amount) to homogeneous phosphorus. Across these three conditions, the growth traits of different Eucalyptus hybrids differed significantly, indicating different adaptabilities of the hybrids to various phosphorus conditions. The growth traits of the aboveground tissues of Eucalyptus under different phosphorus conditions were largely influenced by the morphology of the underground root system. In addition, the root morphology of Eucalyptus under heterogeneous phosphorus treatment suggested that there were two mechanisms for locating nutrients. Eucalyptus hybrids such as Urophylla 3229, Grandis 9, Guanglin 3, 201-2, and Dunn produced more roots proximal to the phosphorus supply; the other hybrids, Urophylla 3216, Grandis 5, and Guanglin 9, relied mainly on the growth of roots opposite the phosphorus supply to obtain adequate nutrients for growth. With these two strategies, a wide range of nutrients was obtained, root distribution was greater, more soil volume was covered, the contact area of the roots with soil phosphorus was increased, and the uptake of phosphorus by the root system was increased. These results demonstrate that Eucalyptus relies on changes to morphological characteristics of the root system to increase accessibility to phosphorus resources.

The aims of this study were to examine the adaptive mechanisms of Neyraudia reynaudiana, a pioneer species rapidly colonizing degraded sites, to heterogeneous phosphorus (P) distribution, and how foraging P distributed in patches affects whole-plant biomass and nutrient accumulation. Plants were grown in equally divided sand-culture boxes using different concentrations of P applied either heterogeneously (0/5, 0/15, 5/15, 0/30, and 15/30 mg KH2PO4 solution/kg dry soil) or homogeneously (2.5/2.5, 7.5/7.5, 10/10, 15/15, and 22.5/22.5 mg kg−1) to each of the split boxes. After 4 months of treatment applications, a significant (p

Restoration of acidic/highly contaminated sites is particularly challenging, and thus practitioners may require targeting stress tolerant species for restoration. Phytoremediation technology is efficient, eco-friendly and cost-effective, and one of the candidate species for phytoremediation of highly acidic mine wastelands is Neyraudia reynaudiana. However, the threshold of acidity above which it becomes inhibitory for emergence and establishment of the species as well as the effect on cellular structure are still unclear. In this study, we specifically aimed to understand how acid stress may affect early life stage processes such as seed germination, and seedling growth and cellular integrity. This was achieved by assessing germination capacity, germination potential and rate, biomass production and plasma membrane integrity in root tips after exposing seeds to a gradient of acid stress (pH 5.5, 4.5, 3.5 and control). The results showed that acid treatment with pH 3.5 adversely affected seed germination and seedling growth of N. reynaudiana, and severely damaged the root apex plasma membrane and the subcellular mitochondria and chloroplasts in the epicotyl. The germination potential and germination rate of seeds treated with acid solution with pH 4.5 were significantly higher by 23–29 % and 5–10 % than those of other acid stress treatments, while the effects of acid treatments with pH 4.5 and 5.5 on root growth and biomass of N. reynaudiana germinants were subtle. It can be concluded that N. reynaudiana tolerates acidity as low as pH 4.5 through maintaining plasma membrane integrity and subcellular structure. From phytoremediation viewpoint, sowing seeds of N. reynaudiana on acidic mine wastes with pH ≥ 4.5 would result in early establishment success.

Single-crystal MoO3 micrometer to millimeter even centimeter belts were prepared via a novel route of oxidizing a discarded molybdenum disilicide heating element at 1000 °C for 3 h. The morphology and structure features, and growth mechanism of the products were evidently investigated by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results indicated that the powdery and fibrous products were typical α-MoO3 belt-like structures which size could develop from micrometer to several millimeter even centimeter in length and up to 0.5 mm in width. It should be formed preferentially along the [001] direction via layer by layer growth to form 1-D single MoO3 belts by vapor-solid mechanism. Thermal and luminescence properties of the products were revealed by thermogravimetric analysis and differential thermal analysis and photoluminescence spectra that the resultant α-MoO3 belts had good thermal stability and characteristics of luminescence with a central peak at 481 nm. The MoO3 belts are of good potential being applied to luminescent and high temperature devices.

Osteolysis is a serious complication of several chronic inflammatory diseases and is closely associated with a local chronic inflammatory reaction with a variety of causes. However, similarities exist in the mechanisms of their pathological processes. Inflammatory factors and oxidative stress-induced nuclear factor κB (NF-κB) and mitogen-activated protein kinases (MAPKs) signaling pathways play a center role in bone erosion. Dihydromyricetin (DMY) is a natural compound with anti-inflammatory and antioxidative effect, which are commonly used in chronic pharyngitis and alcohol use disorders. In the current study, we identified that DMY attenuated lipopolysaccharide (LPS)-induced oxidative stress through inhibiting the production of reactive oxygen species (ROS) and nitric oxide (NO), downregulated COX-2 and iNOS, and promoted the activity of the antioxidative system by activating superoxide dismutase (SOD) and Nrf2/HO-1 pathway. To further investigate the underlying mechanism, we found that DMY inhibits osteoclast (OC) differentiation and bone resorption activity through blocking the RANKL-induced activation of the NF-κB and MAPKs signaling pathways and then downregulated c-Fos and NFATc1, which is essential for OC differentiation. Furthermore, DMY inhibited LPS-induced osteolysis in vivo. Collectively, these results indicate that DMY might be a promising prophylactic antiosteoclastic/resorptive agent in preventing or treating bone lysis diseases.

This chapter explores the representation of time in the films of Hong Kong director Wong Kar-wai. Wong’s films display a strong fascination with temporality, its construction, deconstruction, fragmentation, reconstruction, projection, and retrospection. Memory, nostalgia, and amnesia are recurrent motifs in Wong’s films. His film art embodies the principles of the “time-image” in modern cinema, which is a cinema of fragmentation, self-reflexivity, paradox, double and multiple temporalities, non-linear narrative, and inconclusive endings. Using Gilles Deleuze’s concepts of “movement-image” and “time-image,” the chapter looks at various configurations of time in Wong Kai-wai’s films. It focuses especially on Wong’s informal trilogy: Days of Being Wild (1990), In the Mood for Love (2000), and 2046 (2004), in which Wong uses exemplary time-images to explore problems of time and memory in the changing geopolitical and psychosocial landscapes of Hong Kong, attempting to open up a space for its past to negotiate with its unknown future.

Experiments were conducted to examine the effects of different concentrations of Cd on the performance of the Cd accumulator Conyza canadensis. Cd accumulation in roots and leaves (roots>leaves) increased with increasing Cd concentration in soil. High Cd concentration inhibited plant growth, increased the membrane permeability of leaves, and caused a significant decline in plant height and chlorophyll [chlorophyll (Chl) a, Chl b, and total Chl] content. Leaf ultrastructural analysis of spongy mesophyllic cells revealed that excessive Cd concentrations cause adverse effects on the chloroplast and mitochondrion ultrastructures of C. canadensis. However, the activities of antioxidant enzymes, such as superoxide dismutase, catalase, peroxidase, total non-protein SH compounds, glutathione, and phytochelatin (PC) concentrations, showed an overall increase. Specifically, the increase in enzyme activities demonstrated that the antioxidant system may play an important role in eliminating or alleviating the toxicity of Cd in C. canadensis. Furthermore, results demonstrate that PC synthesis in plant cells is related to Cd concentration and that PC production levels in plants are related to the toxic effects caused by soil Cd level. These findings demonstrate the roles played by these compounds in supporting Cd tolerance in C. canadensis.

Plantations of eucalypts as short-rotation tree crops are rapidly expanding in tropical and sub-tropical regions, including southern China, where the soils are acidic and available phosphorus (P) is limited. We investigated seedling growth, dry matter accumulation, and the dynamics of photosynthetic rate and chlorophyll content of seven Eucalyptus species/hybrids (E. dunnii, E. grandis, E. grandis × E. camaldulensis, E. urophylla × E. camaldulensis, E. urophylla × E. tereticornis, E. grandis × E. tereticornis, E. urophylla × E. grandis) in response to different levels of P supply (0, 6, 12 and 18 mg·kg−1 KH2PO4). The photosynthetic rate and the chlorophyll content significantly declined as the P supply declined in almost a linear fashion for all species as the P stress period extended. In the absence of P supply, height growth of seedlings of all species was significantly impaired, while root collar diameter growth and whole plant dry matter accumulation was not affected by the level of P supply in most of the species. Significant inter-species variations in growth, dry matter accumulation and photosynthetic rate in response to P supply were detected. Eucalyptus dunnii had the lowest growth performance across all levels of P supply while E. Urophylla × E. tereticornis showed superior growth performance. From a practical point of view, E. Urophylla × E. tereticornis is suggested as a candidate hybrid for planting on slightly P-deficient sites in southern China while E. dunnii, being a slow-growing species, is not suitable for short-rotation plantation. On plantation sites where severe P deficiency exists, P fertilization needs to be considered to boost rapid growth of seedlings so as to meet the management objectives of short-rotation plantation.

Reserved capacity for emergent demands plays an important role in medical resource management. In this case, it is crucial to accurately predict the amount of emergent demands in each day for the purpose of management. Based on the data from West China Hospital of Sichuan University, this research applied Artificial Neural Networks (ANNs) in forecasting emergent demand for Computed Tomography (CT) innovatively and accurately; besides, it explored how the network structure and forecasting lead time, affect prediction performance of the networks. The empirical experiments suggested that the performance of ANNs is acceptable (average error is around 15, error ratio: 8.6%) and stable, therefore it lays the foundation for forecasting emergent demands with Artificial Neural Networks of more complex structure, and has a positive meaning for the management of emergent demands in large medical institutions.

Surgery cancellation has a greatly negative impact on both hospital and patient. A commonly used method for improving this problem is analyzing cancellation reasons through statistical analysis, while the improvement is inefficient. Based on surgery data from the hospital information system (HIS) of West China Hospital (WCH), we proposed to use machine learning methods include Random forests (RF), Bagging, Boosting and Bayesian additive regression trees (BART) to predict surgery cancellation. The experimental result shows that the Boosting with Over-sampling performed well in prediction accuracy (Sensitive: 0.5234, Specific: 0.8105, Accuracy: 0.7651 and AUC: 0.6670). And our research also points out the latent causes for surgery cancellation. It's useful for hospital managers.

Telescopes in polarization lidar often modify the input polarization of the return signal, such that the telescope may significantly impact the depolarization estimates of aerosol and introduce error to the polarization lidar measurements. The error cannot be corrected by a traditional calibration constant. We present a method to correct the polarization effect of the telescope. We analyze the polarization effect of a telescope on the basis of the Mueller formalism, and introduce an algorithm for correcting the depolarization parameter of aerosol. A Newton telescope and a Cassegrain telescope are often chosen as the receiver in lidar. Their polarization models are established, and the Mueller matrices are calculated. The components of these matrices are dependent on wavelength, incident angle of the incoming light, and surface properties. The polarization impact of the telescope in lidar can be calibrated by a parameter, and the effects of different telescopes are discussed. The polarization crosstalk induced by the Newton telescope is obvious. The depolarization parameters change greatly with coating and wavelength, and they are calculated and presented. Whereas the crosstalk of a Cassegrain telescope is much smaller, the error can reach the level of 10−3 and can be negligible. The method presented in this paper could also be upgraded by taking into account all of the optical devices instead of only the telescope.