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Abstract Since the 1950s, observations and climate models show an amplification of sea surface temperature (SST) seasonal cycle in response to global warming over most of the global oceans except for the Southern Ocean (SO), however the cause remains poorly understood. In this study, we analyzed observations, ocean reanalysis, and a set of historical and abruptly quadrupled CO2 simulations from the Coupled Model Intercomparison Project Phase 6 archive and found that the weakened SST seasonal cycle over the SO could be mainly attributed to the intensification of summertime westerly winds. Under the historical warming, the intensification of summertime westerly winds over the SO effectively deepens ocean mixed layer and damps surface warming, but this effect is considerably weaker in winter, thus weakening the SST seasonal cycle. This wind‐driven mechanism is further supported by our targeted coupled model experiments with the wind intensification effects being removed.

Marine heatwaves (MHWs) are a type of widespread, persistent, and extreme marine warming event that can cause serious harm to the global marine ecology and economy. This study provides a systematic analysis of the long-term trends of MHWs in the Eastern China Marginal Seas (ECMS) during summer spanning from 1982 to 2022, and occurrence mechanisms of extreme MHW events. The findings show that in the context of global warming, the frequency of summer MHWs in the ECMS has increased across most regions, with a higher rate along the coast of China. Areas exhibiting a rapid surge in duration predominantly reside in the southern Yellow Sea (SYS) and southern East China Sea (ECS, south of 28°N). In contrast, the long-term trends of mean and maximum intensities exhibit both increases and decreases: Rising trends primarily occur in the Bohai Sea (BS) and Yellow Sea (YS), whereas descending trends are detected in the northern ECS (north of 28°N). Influenced jointly by duration and mean intensity, cumulative intensity (CumInt) exhibits a notable positive growth off the Yangtze River Estuary, in the SYS and southern ECS. By employing the empirical orthogonal function, the spatio-temporal features of the first two modes of CumInt and their correlation with summer mean sea surface temperature (SST) and SST variance are further examined. The first mode of CumInt displays a positive anomalous pattern throughout the ECMS, with notable upward trend in the corresponding time series, and the rising trend is primarily influenced by summer mean SST warming. Moreover, both of the first two modes show notable interannual variability. Extreme MHW events in the SYS in 2016 and 2018 are examined using the mixed layer temperature equation. The results suggest that these extreme MHW events originate primarily from anomalous atmospheric forcing and oceanic vertical mixing. These processes involve an anomalous high-pressure system over the SYS splitting from the western Pacific subtropical high, augmented atmospheric stability, diminished wind speeds, intensified solar radiation, and reduced oceanic mixing, thereby leading to the accumulation of more heat near the sea surface and forming extreme MHW events.

Tetrahydrofurfuryl alcohol, a cost-effective biomass derivative, offers a sustainable path for synthesizing 1,5-pentanediol through hydrogenolysis. To develop the efficient production of 1,5-pentanediol from this alcohol, we have prepared a series of MgAl2O4-modified Pt/WOx/γ-Al2O3 catalysts with varying compositions via impregnation–calcination methods. The physicochemical properties of these catalysts were subsequently characterized using diverse techniques. Characterization revealed that magnesia–alumina spinel modification enhanced Pt particle dispersion, CO adsorption on Pt/WOx/γ-Al2O3, reduced Pt particle reduction temperature, diminished the acid content in the catalysts, and increased the surface oxygen vacancy concentration. These alterations appear to influence the catalyst performance, though other factors cannot be ruled out. Catalytic activity tests demonstrated that magnesia–alumina spinel modification improved tetrahydrofurfuryl alcohol hydrogenolysis activity and the 1,5-pentanediol selectivity of Pt/WOx/γ-Al2O3. Optimal performance was achieved at 12% magnesia–alumina spinel loading, with a tetrahydrofurfuryl alcohol conversion of 47.3% and 1,5-pentanediol selectivity of 88.4%.

This study utilized a three-dimensional ocean general circulation model to investigate the intensity, thickness, and width of the three-dimensional deep western boundary current (DWBC) in the South China Sea (SCS). The numerical results show that the DWBC begins near the inlet of the Luzon overflow, flows westward along the northern boundary, proceeds southward along the western boundary, and ultimately terminates at the southern boundary. The mean DWBC’s velocity, thickness, and width is 4.78 cm/s, 1645 m, and 140 km, respectively. Combined with the dynamic results, it is evident that the three-dimensional structure of the DWBC appears to have been visibly weakened after the closure of the deep Luzon overflow. Strong deep mixing has a significantly stronger, thicker, and wider effect on the intensity, thickness, and width of the DWBC. Both the bottom and lateral friction coefficients negatively impact the DWBC in the SCS.

In order to explore the effects of different pretreatment methods (breaking skin, beating pulp, filtering, etc.) on the quality of blueberry powder, vacuum freeze-drying technology was used to prepare blueberry powder, and its physical properties, active components and antioxidant capacity were determined. Meanwhile, the main groups were analyzed by Fourier transform infrared spectroscopy. The results were as follows: The physical properties and antioxidant capacity of blueberry powder prepared by different pretreatment methods were different. Through infrared spectroscopy, the main groups of the three blueberry powders did not change significantly. The whole fruit powder (WP) had good dispersity and the highest contents of total phenol (5.48 mg/g) and anthocyanin (0.69 mg/g), and the strongest antioxidant capacity. Fruit pulp powder (PP) had the lowest water content (5.47%) and the highest solubility (71.38%). Fruit juice powder (JP) had the lowest average particle size (98.62 μm) and the highest glass transition temperature (43.71 ℃). Although WP had lower solubility, it had the strongest antioxidant capacity and could be used for processing nutritional fortifier. PP and JP had good physical properties and high solubility. Besides direct consumption, they could also be pressed for tablet processing or used as raw materials for further processing of solid drinks. The three kinds of blueberry powder had its own advantages and could be developed according to the actual situation.

The exploitation and construction of deep sea is a new direction for human development. In order to meet the national strategic development needs, it should be well planned in advance. Deep sea development is more dependent on the marine environment, and the demand for marine environment information is more urgent. This paper analyzed the fields in which the marine environmental service could play a role in the development and construction of deep sea and the corresponding service contents; from the aspects of navigation, hydrographic surveying and charting, and oceanographic survey, it analyzed the current status of the US and China's capabilities in deep sea marine environment support; then the gap between China and the United States in six aspects was analyzed; at last, some proposals were proposed from a disciplinary perspective.

In order to solve the problem of emergency decision-making with incomplete information and deal with the accident information in different time series at the scenes of major accidents, this paper proposes a method of sequential decision-making by utilizing the relevant knowledge of D-S evidence theory and game theory. Firstly, we took an oil tank fire accident as an example and sorted out historical cases and expert experiences to establish a logical relationship between key accident scenes and accident scene symptoms in the accident. Meanwhile, we applied the logistic regression analysis method to obtain the basic probability distribution of each key accident scene in the oil tank fire, and on this basis, we constructed an evidence set of the fire. Secondly, based on the D-S evidence theory, we effectively quantified the knowledge uncertainty and evidence uncertainty, with the incomplete and insufficient information taken as an evidence system of the development of key accident scenes to construct a situation prediction model of these accident scenes. Thirdly, based on the game theory, we viewed emergency decision-makers and major accidents as two sides of the game to compare and analyze accident states at different time points and solve the contradiction between loss costs of decision-making and information collection costs. Therefore, this paper has provided a solution for the optimization of accident schemes at different time stages, thus realizing the sequential decision-making at the scenes of major accidents. Furthermore, we combined the situation prediction model with sequential decision-making, with the basic steps described below: (1) We drew up an initial action plan in the case of an extreme lack of information; then, we (2) started to address the accident and constructed a framework of accident identification, (3) collected and dealt with the continuously added evidence information with the evolution of the accident, (4) calculated the confidence levels of key accident scenarios after evaluating different evidence and then predicted the accident state in the next stage, and (5) calculated the profit–loss ratio between the current decision-making scheme and the decision-making scheme of the next stage. Finally, we (6) repeated steps (3) to (5) until the accident completely vanished. We verified the feasibility of the proposed method with the explosion accident of the Zhangzhou P.X. project in Fujian on 6 April used as an example. Based on the D-S evidence theory, this method employs approximate reasoning on the incomplete and insufficient information obtained at the scenes of major accidents, thus realizing the situation prediction of key scenes of these accidents. Additionally, this method uses the game theory to solve the contradiction between decision-making loss costs and information collection costs, thus optimizing the decision-making schemes at different time stages of major accidents.

Fermented vegetable-based foods, renowned for their unique flavors and human health benefits, contain probiotic organisms with reported in vitro antioxidative effects. This study investigates the probiotic properties of Latilactobacillus sakei MS103 (L. sakei MS103) and its antioxidant activities using an in vitro oxidative stress model based on the hydrogen peroxide (H2O2)-induced oxidative damage of RAW 264.7 cells. L. sakei MS103 exhibited tolerance to extreme conditions (bile salts, low pH, lysozyme, H2O2), antibiotic sensitivity, and auto-aggregation ability. Moreover, L. sakei MS103 co-aggregated with pathogenic Porphyromonas gingivalis cells, inhibited P. gingivalis-induced biofilm formation, and exhibited robust hydrophobic and electrostatic properties that enabled it to strongly bind to gingival epithelial cells and HT-29 cells for enhanced antioxidant effects. Additionally, L. sakei MS103 exhibited other antioxidant properties, including ion-chelating capability and the ability to effectively scavenge superoxide anion free radicals, hydroxyl, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid, and 2,2-diphenyl-1-picrylhydrazyl. Furthermore, the addition of live or heat-killed L. sakei MS103 cells to H2O2-exposed RAW 264.7 cells alleviated oxidative stress, as reflected by reduced malondialdehyde levels, increased glutathione levels, and the up-regulated expression of four antioxidant-related genes (gshR2, gshR4, Gpx, and npx). These findings highlight L. sakei MS103 as a potential probiotic capable of inhibiting activities of P. gingivalis pathogenic bacteria and mitigating oxidative stress.

Objective: To explore the comprehensive quality characteristics of blueberries. Methods: 20 indexes including sensory morphology, nutritional function, free amino acids and volatile flavor substance content of six varieties of blueberries in Sichuan were detected by automatic amino acid analyzer and gas chromatography-mass spectrometry and other instruments. Furthermore, its comprehensive quality was evaluated by the principal component analysis and cluster analysis. Results: There were differences among different blueberry varieties. The single fruit weight (2.06 g) and transverse diameter (14.39 mm) of Brigita were the highest, while the gumminess (151.96 N) and total phenol content (1.64 mg/g) were the lowest; Mistry had the highest free amino acid content (453.72 mg/100 g), and the proportion of umami and sweet amino acids was higher; Emerald had the lowest free amino acid content (122.93 mg/100 g) and the least variety; Gardenblue had moderate hardness, its sugar-acid ratio (28.23), anthocyanin content (2.09 mg/g), total phenol content (5.78 mg/g) and flavor substances content (14.60 μg/g) were the highest. Conclusions: According to principal component analysis, the optimal variety was Gardenblue. Cluster analysis divided blueberries into three categories, suitable for fresh-eating varieties including Gardenblue and Legacy; suitable for both processing and fresh-eating varieties were Emerald, Brigitta and Misty; while Bluerain had outstanding processing advantages.

Abstract Background Spray-as-you-go (SAYGo) airway topical anesthesia and nerve block are common techniques used during awake tracheal intubation. However, their effects have not been described during double-lumen tube intubation. We report on a prospective randomized study that aimed to compare the intubation effects of SAYGo and nerve block patients undergoing thoracic surgery. Methods Sixty-six American Society of Anesthesiologists (ASA) physical status I and II patients were scheduled to undergo double-lumen tube (DLT) tracheal intubation for thoracic surgery. The patients were randomly assigned into control (Group C), ultrasound (Group U), and flexible intubation scope (Group F) groups with 22 cases in each group. Patients in Group C were induced with a standard anesthetic regimen. Patients in Groups U and F were treated with superior laryngeal nerve (SLN) block combined with transtracheal injection (TTI) and given a SAYGo airway topical anesthesia before intubation. Hemodynamic variables during intubation process were recorded as the primary outcome. Additional patient data were recorded including the occurrence of adverse events, the level of hoarseness, the occurrence of sore throats, memory function and the level of patient satisfaction with anesthesia. Results The blood pressure (BP) and heart rate (HR) of patients in group C was significantly increased 1 min after tracheal intubation (P

The oceanic bottom mixed layer (BML) plays an important role in transporting mass, heat, and momentum between the ocean interior and the bottom boundary. However, the spatial-temporal characteristics of the BML in the South China Sea (SCS) is not well understood. Using 514 full-depth temperature and salinity profiles collected during the time period from 2004 to 2018 and two particularly deployed hydrographic moorings, the temporal and spatial variations of the BML have been analyzed. The results show that the BML in the SCS exhibits significant inhomogeneity, with thickness and stability varying across different regions. Specifically, the BML is relatively thin and stable over the continental shelf and deep-sea regions, while it is thicker and less stable over the northern continental slope. The mean, median, and one standard deviation values of BML thickness over the entire SCS were found to be 73 m, 56 m, and 55 m, respectively. Further analysis reveals that energetic high-frequency dynamic processes, coupled with steep bottom topography, contribute to strong tidal dissipation and vertical mixing near the bottom over the continental slope, resulting in thicker BMLs. Conversely, dynamic processes in the deep ocean are less energetic and low-frequency, the topography is relatively smooth, and tidal dissipation and bottom vertical mixing are weaker, leading to a thinner BML. These findings enhance our understanding of the BML dynamics in the SCS and other marginal seas and provide insights to improve parameterizations of physical processes in ocean models.

In this thesis, four varieties of mangoes (Dahuang mango, Daqing mango, eagle-mouth mango, Tai mango), which were all out put in Panzhihua, were investigated as the research objects. The comprehensive evaluation of the four varieties of mangoes was carried out by measuring their various nutritional components combined with their volatile aroma components. In the meantime, the principal component analysis (PCA) was established on the nutritional components. The results showed that there were obvious differences in the quality of the four varieties of mangoes. The highest sugar-acid ratio and β-carotene content belonged to Dahuang mango, which were 16.47 and 4.06 mg/100 g, respectively. The highest water content, content of soluble sugar, titratable acid and total phenols belonged to eagle-mouth mango, which were 82.96%, 21.22%, 2.03% and 0.73 mg/g, respectively. The highest soluble protein content belonged to Tai mango, which was 7.83 mg/g, respectively. Principal component analysis (PCA) results showed that the mango evaluation system can be characterized by two principal components. The highest comprehensive score was eagle-mouth mango, the second was Tai mango, the third was Dahuang mango, and the fourth was Daqing mango. The proportions of terpenoids in the four varieties of mangoes from high to low were Dahuang mango, eagle-mouth mango, Tai mango and Daqing mango. This research provided a theoretical basis for the development of Panzhihua mango industry.

To address the issue of current garbage cleanup vessels being limited to performing garbage cleaning operations in the ocean, without the capability of transferring the garbage from the ocean to the land, this paper presents a spiral-propulsion amphibious intelligent robot for land garbage cleaning and sea garbage cleaning. The design solution is as follows. A mechanical structure based on a spiral drum is proposed. The interior of the spiral drum is hollow, providing buoyancy, allowing the robot to travel both on marshy, tidal flats and on the water surface, in conjunction with underwater thrusters. Additionally, a mechanical-arm shovel is designed, which achieves two-degrees-of-freedom movement through a spiral spline guide and servo, facilitating garbage collection. Our experimental results demonstrated that the robot exhibits excellent maneuverability in marine environments and on beach, marsh, and tidal flat areas, and that it collects garbage effectively.

Adenosine is an endogenous substance that regulates sleep homeostasis. It plays an important role in sleep induction under physiological condition. So far, the neural mechanisms underlying sleep-promoting effects of adenosine are not completely clear. Recent studies have shown that glutamatergic neurons in the paraventricular hypothalamic nucleus (PVH) play an important role in wakefulness. Using whole-cell patch-clamp, we found that adenosine can inhibit glutamatergic neurons in PVH. This inhibition is mainly achieved by activating adenosine type 1 receptors, thereby reducing hyperpolarization-activated cyclic nucleotide-gated cation channels. By recording electroencephalogram (EEG) and electromyography (EMG), it was found that local administration of adenosine type 1 receptor blocker in PVH could significantly reduce the NREM sleep. On the contrary, if adenosine was given, it could increase the NREM sleep. These results suggest that adenosine can promote sleep by reducing the excitability of PVH neurons. This findings reveal a novel mechanism of adenosine regulating sleep homeostasis.

Our study aimed to identify a design which would reduce cutting resistance during the harvesting of castor. This paper presents a theoretical study of the wave-type disc cutter, which plays an important role in castor harvesting. Based on the SPH–FEM coupling algorithm, a combined orthogonal rotation experiment was performed to study the effects of disc cutter thickness, edge angle, disc cutter rotation speed, and feeding speed on the maximum cutting force. The response surface method was used to achieve an optimal combination of all the test factors. Mathematical modeling of the maximum cutting force and influencing factors was utilized to obtain the optimal parameters for a cutting system consisting of wave-type disc cutters. The optimal results were obtained with a computer-simulated disc cutter rotation speed of 844.2–942.1 r/min, a feeding speed of 0.89–1.01 m/s, a disc cutter thickness of 2.71–3.15 mm, and an edge angle of 29.2–33.9°. Under these conditions, the maximum cutting force was less than 50 N. Finally, the experimental data and numerical computer simulation results were compared using cutting performance test verification. The analysis found that the test results and simulation results were largely consistent. Therefore, the simulation model was judged to be effective and reasonable.

This study theoretically analyzed the cutting process of castor and determined the structural parameters of the key component of the castor disc-cutting device, aiming to obtain the optimal operation parameter combination and reduce the cutting resistance and power consumption during the harvesting process. The effects of the cutting-disc thickness, cutting-disc rotational speed, feeding speed, and edge angle on the cutting power consumption were studied using an orthogonal rotation combination experiment. The response surface method was used to optimize the parameters, and the mathematical relationship model between the cutting power consumption and each factor was established to determine the optimal parameter combination for disc cutting. The simulation results showed that the optimal combination of cutting parameters was cutting-disc thickness of 3 mm, cutting-disc rotational speed of 550 r/min, feeding speed of 0.6 m/s, and edge angle of 20°. Under these conditions, the cutting power consumption was 1.20375 J. The test results were basically consistent with the model prediction results. Therefore, this study provided a theoretical basis and reference for the design and improvement of castor harvesters.

We compare the vortex evolutions of eyewall replacement cycles (ERCs) between the sea-surface and the free-atmosphere levels and investigate the asymmetric structure of concentric eyewalls (CEs) by examining a combination of aircraft observations and surface wind fields derived from C-band spaceborne synthetic aperture radar (SAR) images during Hurricane Irma (2017) from 4 September 2017 to 8 September 2017. A total of 116 radial wind profiles measured by an aircraft were collected and showed that ERCs occur at both the sea-surface and the free-atmosphere levels. The outer eyewall was shown to form at the free atmospheric level (~3 km) with a narrow structure at the sea-surface level and an outward tilt with height in the cross-section. In our study, four ERC events were determined from wind profile parameters fitted by a modified Rankine vortex model, which was validated by 328 radial legs collected from six hurricanes. The outer eyewall did not replace the inner eyewall at the sea-surface level in the third ERC, due to the maintenance of a short duration and intense original eyewall. Additionally, Irma’s intensity weakened during the fourth ERC rather than re-intensified, because of the generation of a third wind maximum outside the secondary eyewall. Comparisons of five SAR-derived surface wind fields in Irma and another two hurricane cases illustrated that the location of the secondary eyewall generation is a key point in the interpretation of anomaly intensity changes in the fourth ERC.

Based on the satellite observed sea surface temperature (SST), the recovery of SST cooling induced by the tropical cyclones (TCs) over the northwestern Pacific Ocean is investigated. The results show that the passage of a TC induces a mean maximum cooling in the SST of roughly −1.25 °C. It was also found that most of this cooling (~87%) is typically erased within 30 days of TC passage. This recovery time depends upon the degree of cooling, with stronger (weaker) SST cooling corresponding to longer (shorter) recovery time. Further analyses show that the mixed layer depth (MLD) and the upper layer thermocline temperature gradient (UTTG) also play an important role in the SST response to TCs. The maximum cooling increases ~0.1 °C for every 7 m decrease in the MLD or every 0.04 °C/m increase in the UTTG. The combined effects of MLD and TC intensity and translation speed on the SST response are also discussed.

We analyze the projected sea level rise (SLR) for the 21st century for the China Seas (the Bohai Sea, Yellow Sea, East China Sea, and South China Sea) using the Coupled Model Intercomparison Project Phase 5 dataset. We find that the projected SLR over the shallow continental shelves of the China Seas is nearly the same as the global mean sea level change in all future emission scenarios, with a magnitude of 43.6 cm (20.8–67.7 cm, 90% confidence interval) in RCP2.6 and 74.5 cm (41.7–112.8 cm, 90% confidence interval) in RCP8.5 by the year 2100 relative to 1986–2005. We further analyze the causes of SLR and find that more than 90% of the total projected SLR over the continental shelves of the China Seas will result from mass contributions and only a minor contribution will result from local steric height adjustments. This increase in water mass over the continental shelves is not only caused by the loss of land ice, but also from the change in sterodynamic, which tends to push water mass onto the continental shelves from the open oceans.

Recent years have witnessed the great success of image super-resolution based on deep learning. However, it is hard to adapt a well-trained deep model for a specific image for further improvement. Since the internal repetition of patterns is widely observed in visual entities, internal self-similarity is expected to help improve image super-resolution. In this paper, we focus on exploiting a complementary relation between external and internal example-based super-resolution methods. Specifically, we first develop a basic network learning external prior from large scale training data and then learn the internal prior from the given low-resolution image for task adaptation. By simply embedding a few additional layers into a pre-trained deep neural network, the image-adaptive super-resolution method exploits the internal prior for a specific image, and the external prior from a well-trained super-resolution model. We achieve 0.18 dB PSNR improvements over the basic network’s results on standard datasets. Extensive experiments under image super-resolution tasks demonstrate that the proposed method is flexible and can be integrated with lightweight networks. The proposed method boosts the performance for images with repetitive structures, and it improves the accuracy of the reconstructed image of the lightweight model.