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In monomictic lakes, the potential intensification of hypolimnetic deoxygenation due to human activities and climate change threatens lake ecosystems and water quality. Understanding the trends and mechanisms of hypolimnetic deoxygenation would allow for the adaptive management of monomictic lakes. This study investigated the trends and drivers of hypolimnetic deoxygenation in Lake Fuxian (a monomictic lake in south-western China) over the past 150 years using paleolimnological evidence and historical records. Analysis of enrichment factors for molybdenum (Mo), uranium (U), and vanadium (V), and ratios of U/thorium (Th), pristane (Pr)/phytane (Ph), and total organic carbon (TOC)/total phosphorus (TP) in a dated sediment core indicated that the extent of hypolimnetic deoxygenation was relatively low before 1994 and increased substantially thereafter. Nutrient monitoring records and sediment n-alkane proxies indicated notable eutrophication of the lake since 1986 and a greater degree of human disturbance in the catchment between 1951 and 1967. Due to their asynchronous occurrence, eutrophication and catchment disturbance could not be the major drivers of hypolimnetic deoxygenation. Interestingly, climate records indicated that the local ambient temperature exhibited similar trends to that of hypolimnetic deoxygenation, including markedly higher temperatures after 1994. This implies that prolonged water column stratification due to climate warming could have promoted hypolimnetic deoxygenation by limiting oxygen exchange between the upper and lower water columns. In comparing the results with those of Lake Erhai, another monomictic lake with contrasting morphology and hydrology characteristics, we found that the low surface area/depth ratio and long water residence time in Lake Fuxian enable dissolved oxygen of the lake hypolimnion vulnerable to temperature over the lake.

Effective thermal management measures are of great significance for improving the reliability of relay protection equipment. Firstly, the paper establishes a temperature calculation function for components based on the thermal superposition model, calculates the minimum heat dissipation distance between components, and converts the functional coordination of components into coordinate constraints. An optimised layout scheme for components is obtained quickly based on the minimum heat dissipation distance and coordinate constraints. The finite element simulation results show that the optimized layout significantly improves the temperature of the components, with a maximum temperature reduction of 8.6%. Then a component overheating warning strategy is proposed based on state recognition. The life-accelerated decay ratio of the components is calculated by monitoring the operating temperature, and the allowable operating time and alarm signal of the components at a specific temperature are combined to reflect the components’ status accurately.

In recent years, the widespread dissemination of tampered text images on the Internet constitutes an important threat to the security of text images.However, the corresponding tampered text detection (TTD) methods have not been sufficiently explored.The TTD task aims to locate all text regions in an image while judging whether the text regions have been tampered with according to the authenticity of the texture.Thus, different from the general text detection task, TTD task further needs to perceive the fine-grained information for real-world and tampered text classification.TTD task has two main challenges.One the one hand, due to the high similarity in texture between real-world texts and tampered texts, TTD methods that only learn from RGB domain features have limited capability to distinguish these two-category texts well.On the other hand, as the different detecting difficulty exists in real-world texts and tampered texts, the network cannot well balance the learning process of the two-category texts, resulting in the imbalance detection performance between real-world and tampered texts.Compared with RGB domain features, the discontinuity of text texture in frequency domain can help the network to identify the authenticity of text instances.Accordingly, a new TTD method based on RGB and frequency information relationship modeling was proposed.The features in the RGB and frequency domains were extracted by independent feature extractors respectively.Thus, the identification ability of tampered texture can be enhanced by introducing frequency information during the texture perception.Then, a global RGB-frequency relationship module (GRM) was introduced to model the texture authenticity relationship between different text instances.GRM referred to the RGB-frequency features of other text instances in the same image to assist in judging the authenticity of the current text instance, which solved the problem of imbalanced detection performance.Furthermore, a new TTD dataset (Tampered-SROIE) was proposed to evaluate the effectiveness of proposed method, which contains 986 images (626 training images and 360 test images).By evaluating on the Tampered-SROIE, the proposed method obtains 95.97% and 96.80% in F-measure for real-world and tampered texts respectively and reduces the imbalanced detection accuracy by 1.13%.The proposed method will give new insights to the TTD community from the perspective of network structure and detection strategy.Tampered-SROIE also provides an evaluation benchmark for future TTD methods.

Fully ceramic microencapsulated (FCMTM) fuels, proposed as an accident tolerant fuel in light water reactors (LWRs), consists of tri-structural isotropic (TRISO) fuel particles and silicon-carbide ceramic matrix. To ensure the in-pile service safety with improving the fuel economy simultaneously, FCM fuels should be optimally designed. The effects of TRISO particle volume fraction, particle distribution pattern and irradiation conditions on the thermal–mechanical behavior in FCM fuel pellets are investigated via the self-developed code TMAIMF(Thermo-mechanical Analysis of Inert Matrix Fuels). The evolution results of temperature, deformation and stress fields with the increase of burnup indicates that (1) when the particle volume fraction increases from ∼ 15 % to ∼ 43 %, the central temperature gives a rise of ∼ 10 % at 19 % FIMA (fissions per initial heavy metal atoms); the radial size increment will be shortened; while, the maximum tensile stresses of each coating layer of the TRISO particles are slightly varied; (2) the results of temperature, deformation and maximum tensile stress have weak correlations with the fuel particle distribution pattern; (3) the integrity of FCM pellets can be maintained at high fission rate conditions and extended burnup levels; (4) the finite element models with the axial displacement constrained are representative, which can obtain more conservative analysis results than the free-end models. The numerical simulation results demonstrate that the TRISO-particle-based fuel pellets could be flexibly optimized to satisfy the demands of economy and safety.

Abstract Background Recaticimab (SHR-1209, a humanized monoclonal antibody against PCSK9) showed robust LDL-C reduction in healthy volunteers. This study aimed to further assess the efficacy and safety of recaticimab in patients with hypercholesterolemia. Methods In this randomized, double-blind, placebo-controlled phase 1b/2 trial, patients receiving stable dose of atorvastatin with an LDL-C level of 2.6 mmol/L or higher were randomized in a ratio of 5:1 to subcutaneous injections of recaticimab or placebo at different doses and schedules. Patients were recruited in the order of 75 mg every 4 weeks (75Q4W), 150Q8W, 300Q12W, 150Q4W, 300Q8W, and 450Q12W. The primary endpoint was percentage change in LDL-C from the baseline to end of treatment (i.e., at week 16 for Q4W and Q8W schedule and at week 24 for Q12W schedule). Results A total of 91 patients were enrolled and received recaticimab and 19 received placebo. The dose of background atorvastatin in all 110 patients was 10 or 20 mg/day. The main baseline LDL-C ranged from 3.360 to 3.759 mmol/L. The least-squares mean percentage reductions in LDL-C from baseline to end of treatment relative to placebo for recaticimab groups at different doses and schedules ranged from −48.37 to −59.51%. No serious treatment-emergent adverse events (TEAEs) occurred. The most common TEAEs included upper respiratory tract infection, increased alanine aminotransferase, increased blood glucose, and increased gamma-glutamyltransferase. Conclusion Recaticimab as add-on to moderate-intensity statin therapy significantly and substantially reduced the LDL-C level with an infrequent administration schedule (even given once every 12 weeks), compared with placebo. Trial registration ClinicalTrials.gov , number NCT03944109

Objective: Epileptic seizure prediction based on scalp electroencephalogram (EEG) is of great significance for improving the quality of life of patients with epilepsy. In recent years, a number of studies based on deep learning methods have been proposed to address this issue and achieve excellent performance. However, most studies on epileptic seizure prediction by EEG fail to take full advantage of temporal-spatial multi-scale features of EEG signals, while EEG signals carry information in multiple temporal and spatial scales. To this end, in this study, we proposed an end-to-end framework by using a temporal-spatial multi-scale convolutional neural network with dilated convolutions for patient-specific seizure prediction. Methods: Specifically, the model divides the EEG processing pipeline into two stages: the temporal multi-scale stage and the spatial multi-scale stage. In each stage, we firstly extract the multi-scale features along the corresponding dimension. A dilated convolution block is then conducted on these features to expand our model’s receptive fields further and systematically aggregate global information. Furthermore, we adopt a feature-weighted fusion strategy based on an attention mechanism to achieve better feature fusion and eliminate redundancy in the dilated convolution block. Results: The proposed model obtains an average sensitivity of 93.3%, an average false prediction rate of 0.007 per hour, and an average proportion of time-in-warning of 6.3% testing in 16 patients from the CHB-MIT dataset with the leave-one-out method. Conclusion: Our model achieves superior performance in comparison to state-of-the-art methods, providing a promising solution for EEG-based seizure prediction.

Abstract Background Genetic variations in key DNA repair genes may influence DNA repair capacity, DNA damage and breast carcinogenesis. The current study aimed to estimate the association of APEX1 and OGG1 polymorphisms with the risk of breast cancer development. Methods A total of 518 patients with histopathologically confirmed breast cancer and 921 region- and age-matched cancer-free controls were genotyped for the APEX1 polymorphisms rs3136817 and rs1130409 and the OGG1 polymorphisms rs1052133 and rs2072668 using a QuantStudio™ 12 K Flex Real-Time PCR System. Results The rs3136817 heterozygous TC genotype along with the rs3136817 dominant model (TC + CC) was strongly associated with breast cancer susceptibility (odds ratio [OR] = 0.670, 95% confidence interval [95% CI]: 0.513 - 0.873, P = 0.003; OR = 0.682, 95% CI: 0.526 - 0.883, P = 0.004, respectively). No significant associations were observed among rs1130409, rs1052133, rs2072668 and breast cancer risk. Furthermore, an allele combination analysis revealed that APEX1 haplotypes containing C-T (alleles rs3136817 and rs1130409) conferred a significantly lower risk (corrected P

Abstract Background Oral squamous cell carcinoma (OSCC) is one of the most common types of malignancy. Semaphorin 3F (SEMA3F) is highly conserved but present at a lower level in various cancers than in healthy tissues. While it has been reported that SEMA3F is involved in cancer cell proliferation, migration and invasion, its function in OSCC remains unknown. Methods The expression of SEMA3F in OSCC tissues and OSCC-derived cells was analyzed using qRT-PCR and western blotting. Using SAS and HSC2 cells, we also monitored the effect of SEMA3F on OSCC cell proliferation, migration and invasion using MTT, colony formation and transwell assays. The function of SEMA3F in OSCC tumor formation was also assessed in vivo. Results SEMA3F was significantly downregulated in OSCC tissues and OSCC-derived cells. SEMA3F shows growth inhibitory activity in SAS and HSC2 cells and may act as a tumor suppressor. It can inhibit the migration and invasion potential of OSCC cells. Our results also demonstrate that SEMA3F can suppress the growth of OSCC cells in vivo. Conclusions This study revealed that SEMA3F plays a role as a tumor suppressor in OSCC cell proliferation, migration and invasion. Our finding provides new insight into the progression of OSCC. Therapeutically, SEMA3F has some potential as a target for OSCC treatment, given sufficient future research.

Compressive Sensing (CS) has proved to be an effective theory in the field of image acquisition. However, in order to distinguish the difference between the measurement matrices, the CS imaging system needs to have a higher signal sampling accuracy. At the same time, affected by the noise of the light path and the circuit, the measurements finally obtained are noisy, which directly affects the imaging quality. We propose a dual-optical imaging system that uses the bidirectional reflection characteristics of digital micromirror devices (DMD) to simultaneously acquire CS measurements and images under the same viewing angle. Since deep neural networks have powerful modeling capabilities, we trained the filter network and the reconstruction network separately. The filter network is used to filter the noise in the measurements, and the reconstruction network is used to reconstruct the CS image. Experiments have proved that the method we proposed can filter the noise in the sampling process of the CS system, and can significantly improve the quality of image reconstruction under a variety of algorithms.

Our previous investigation found that Ginkgo extract EGb761 could attenuate the depressive-like behaviours induced by a single injection of lipopolysaccharide in mice. However, it has not been investigated whether EGb761 is effective on depressive-like behaviours induced by long-term light deprivation and whether its effects are associated with the inhibition of NF-κB-IL-6 signalling pathway. In this study, three groups (vehicle group, EGb761 low-dose group, and EGb761 high-dose group) of C57BL/6J male mice were exposed to constant darkness for four weeks. The control mice remained on a 12 : 12 light-dark cycle. Depressive-like behaviours were evaluated by tail suspension test (TST), forced swim test (FST), and sucrose preference test (SPT). Spontaneous locomotor activity was evaluated by open field test (OFT). Levels of IL-6, IL-6 mRNA, NF-κB p65, phospho-NF-κB p65, IκBα, and phospho-IκBαwere measured using Elisa, western blotting, or PCR assays. NF-κB p65 DNA binding activity was evaluated using Chemi Transcription Factor Assay Kit. Results showed long-term light deprivation prolonged the immobile time in TST and FST, shortened the latency to immobility in FST, reduced spontaneous locomotor activity in OFT, decreased sucrose preference in SPT, and increased levels of IL-6, IL-6 mRNA, NF-κB p65, phospho-NF-κB p65, and phospho-IκBα in hippocampal tissue. EGb761 dose-dependently reversed the changes of the above parameters induced by long-term light deprivation, without affecting spontaneous locomotor activity. We conclude that EGb761 could attenuate the depressive-like behaviours and inhibit the NF-κB-IL-6 signalling pathway in a light-deprivation-induced mouse model of depression.

The urban heat island effect caused by the rapid increase in urban anthropogenic heat has gradually become an important factor affecting the living environment of urban residents. Studying the temporal and spatial variation characteristics of urban anthropogenic heat is of great significance for urban planning and urban ecological service systems. In this study, the urban anthropogenic heat flux (AHF) in 2004, 2009, 2014, and 2020 in the central urban area of Guangzhou was retrieved based on Landsat data and the surface energy balance equation, and the temporal and spatial characteristics of different types of anthropogenic heat were explored by combining the transfer matrix and the migration of the gravity center. The results showed that: (1) The overall change trend of anthropogenic heat in the central urban area of Guangzhou was enhanced, and the degree of enhancement was related to the type of urban functional land. (2) Different types of anthropogenic heat had different characteristics in terms of area expansion and spatial changes. Low-value anthropogenic heat (zero-AHF zone, low-AHF zone, medium-AHF zone) changed drastically in terms of area expansion. High-value anthropogenic heat (medium-AHF zone, high-AHF zone) changed more drastically in space. The increase in urban population, rapid economic development, and increased industrial production activities have stimulated the emission of anthropogenic heat, which has a positive impact on the intensity of anthropogenic heat.

How fish communities change with eutrophication in temperate lakes is well documented, while only a few studies are available from subtropical lakes. We investigate the fish community structure in 36 lakes located in the Yangtze River basin, covering a wide nutrient gradient. We found that fish species richness and total fish catch per unit effort (CPUE) increased significantly with chlorophyll a (Chla). Among the different feeding types, the proportion of zooplanktivores increased significantly with Chla, while the percentage of omnibenthivores showed no obvious changes; the CPUE of piscivorous Culter spp. increased with Chla, while their proportion of total catch decreased pronouncedly. Based on the index of relative importance (IRI), the most important and dominant fish species was the zooplanktivorous Sijiao (Toxabramis swinhonis), followed by the omniplanktivorous sharpbelly (Hemiculter leucisculus) and the omnibenthivorous crucian carp (Carassius carassius), a small-sized species belonging to the Cyprinidae family. The CPUE of these three species increased significantly with Chla. The focus has, so far, been directed at large fish, but as emphasized by our results, the abundant small fish species were dominant in our subtropical study lakes even in terms of biomass, and, accordingly, we recommend that more attention be paid to the population dynamics of these species in the future.

Eutrophication of lakes often results in dominance of cyanobacteria, which may potentially lead to serious blooms and toxic water. However, cyanobacterial detritus may act as an important carbon source for aquatic organisms. Using stable isotope carbon (13C) as a tracer, we assessed the carbon transfer from cyanobacteria to pelagic and benthic consumers in a 28-day outdoor mesocosm (~130 L) labelling experiment established in Lake Taihu, China, during a Microcystis aeruginosa bloom. The different organisms were labelled differently after addition of the labelled Microcystis detritus to the water. δ13C of particulate organic matter and of cladoceran zooplankton peaked earlier than for larger invertebrate consumers. Among the pelagic species, Daphnia similis had the highest Δδ13C, while the two snail species Radix swinhoei and Bellamya aeruginosa had lower but similar Δδ13C. The bivalves showed relatively modest changes in δ13C. The δ13C of Anodonta woodiana and Unio douglasiae showed a marginal though not significant increase, while a marked increase occurred for Arconaia lanceolate peaking on day 20, and Corbicula fluminea a slight increase peaking on day 9. Our results suggest that carbon from cyanobacteria can be incorporated by pelagic and some benthic consumers and eventually be transferred to higher trophic levels. Cyanobacterial carbon may, therefore, be considered an important carbon source supporting the entire food web during blooms, even if the cyanobacteria are not consumed directly.

The near space airships usually have a large volume. when the airship leave the boathouse, it is influenced by the near surface wind significantly, and the attitude of the airship will change, and the risk of the experiment will be increase. In this paper, the dynamics method is used to analyse the force in the mooring rope and the attitude of the airship with nosecone constraint. The kinetic equation is established. A typical near space airship is choose as an example. The Runge- Kutta method is used to solve the dynamic equation. According to calculation result, the change law of the force in the mooring rope and the attitude of the airship is given, which can provide reference for the near space airship experiment. For the airport in this paper, the force in the mooring rope near the tail in the windward side is bigger than the others. The stronger rope should be used in design.

Evolution of resistance by insects threatens the continued success of pest control using insecticidal crystal (Cry) proteins from the bacterium Bacillus thuringiensis (Bt) in sprays and transgenic plants. In this study, laboratory selection with Cry1Ac yielded five strains of cotton bollworm, Helicoverpa armigera, with resistance ratios at the median lethal concentration (LC50) of activated Cry1Ac ranging from 22 to 1700. Reduced activity and reduced transcription of an alkaline phosphatase protein that binds Cry1Ac was associated with resistance to Cry1Ac in the four most resistant strains. A Cry1Ac-binding fragment of alkaline phosphatase from H. armigera (HaALP1f) was not toxic by itself, but it increased mortality caused by Cry1Ac in a susceptible strain and in all five resistant strains. Although synergism of Bt toxins against susceptible insects by toxin-binding fragments of cadherin and aminopeptidase N has been reported previously, the results here provide the first evidence of synergism of a Bt toxin by a toxin-binding fragment of alkaline phosphatase. The results here also provide the first evidence of synergism of a Bt toxin by any toxin-binding peptide against resistant insects.