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Quantitative evaluation of rock dynamic disaster intensity is a challenging and difficult task in the field of earth science. In this article, the dynamic compression tests of granite under different impact velocities are carried out, and the energy evolution characteristics of the dynamic failure process of granite are analyzed. The dynamic fracture characteristics of granite were studied by using computed tomography and section scanning equipment. The results show that the energy dissipation and energy accumulation mechanism of granite under dynamic loading are fundamentally changed with the increase of impact disturbance strength, which leads to the transformation of the failure mode from the tension-type sheet crack under low-speed impact to the complex network crack coupled by tension and shear under high-speed impact. At the same time, the greater the impact velocity, the larger the macroscopic crack density, the more uneven the particle distribution on the fracture section, the greater the roughness, and the higher the rock mass fracture degree. In accordance with the results, the energy distribution ratio is proposed to quantitatively characterize the coupling effect of energy dissipation and energy accumulation in the dynamic failure process of granite and to reflect its dynamic failure intensity. The higher the energy distribution ratio, the stronger the energy coupling effect and the more intense the dynamic failure of the rock mass.

The marine biological functional products industry refers to the extraction of active ingredients from marine organisms, it is an important part of the marine biopharmaceutical industry to develop production activities with marine characteristics, such as biological materials, medical devices, dietary supplements, functional foods, daily necessities and agricultural products. In recent years, the research and industrialization of marine biological functional products have become a hot field, showing a sustained and rapid growth trend, which can not only promote the development of marine economy and health industry, moreover, it provides a new way to ensure human health, which is deeply matched with the requirements of efficient exploitation of marine resources and high-tech applications. The market prospects are broad and the growth potential is enormous. Shandong is a major province of marine industry, and has made great progress in the development of the marine biological functional products industry in recent years. However, the problems such as low conversion rate of scientific achievements, difficulty in financing, serious homogeneity of products, weak support system and unreasonable distribution of talents which restrict its high-quality development to a certain extent. In the future, we should take more focus on strengthening the innovation ability of enterprises, giving full play to the demonstration effect of industrial base agglomeration, formulating efficient financing measures, promoting the transformation of scientific achievements, and attracting high-end talents.

Abstract Threaded fasteners are one of the most commonly used connection methods for mechanical structures. Its primary function is to generate appropriate clamping forces and fasten the connected parts. An inappropriate preload can cause loosening, fatigue fracture, and other problems. This will affect the safety and reliability of mechanical equipment. The precise control of the preload has become a critical issue in mechanical assembly processes. Over the past few decades, various tightening measures and methods have been proposed to address this issue. However, many problems continue to exist with practical applications that have not been reviewed comprehensively and systematically. First, various control methods were summarized systematically, and their advantages and disadvantages in engineering applications were analyzed. Torque control is the most widely used tightening method owing to its simple operation and low cost. Therefore, the research on the torque control method was summarized systematically from three aspects: the torque–preload correlation formula, effective friction radius, and friction characteristics during tightening. In addition, the special circumstances that may increase preload uncertainty were discussed. Finally, based on a summary of the current research status, the prospects for future research were discussed. This study would aid researchers in extensively understanding the problems in preload control.

On-orbit processing is an important research direction in the real-time remote sensing detection of earth's surface anomalies (ESSA). However, existing methods cannot comprehensively utilize multi-dimensional remote sensing characteristics to detect multi-type ESSA simultaneously. Meanwhile, it is difficult to realize the comprehensive utilization of multi-dimensional remote sensing characteristics for the limited storage and computing resources on satellites. Therefore, this study proposed a detection method for multi-type ESSA based on multi-dimensional feature space. The proposed method first selected the remote sensing characteristics reflecting the basic earth's surface elements to construct a multi-dimensional feature space and proposed two comprehensive remote sensing characteristics. Then, these characteristics were used to build a prior knowledge base reflecting the normal earth's surface conditions. Finally, by comparing the real-time acquired data and prior knowledge base, this study completed ESSA detection. The validation results indicated that the proposed method can effectively detect multi-type ESSA with an accuracy of over 85%. Moreover, the proposed method simplifies the large and complex ESSA remote sensing characteristic system, which greatly reduces the complexity of ESSA detection methods and increases the possibility of on-orbit processing.

Plants produce diverse flavonoids for defense and stress resistance, most of which have health benefits and are widely used as food additives and medicines. Methylation of the free hydroxyl groups of flavonoids, catalyzed by S-adenosyl-l-methionine-dependent O-methyltransferases (OMTs), significantly affects their physicochemical properties and bioactivities. Soybeans (Glycine max) contain a rich pool of O-methylated flavonoids. However, the OMTs responsible for flavonoid methylation in G. max remain largely unknown. We screened the G. max genome and obtained 22 putative OMT-encoding genes that share a broad spectrum of amino acid identities (25–96%); among them, 19 OMTs were successfully cloned and heterologously expressed in Escherichia coli. We used the flavonoids containing the free 3, 5, 7, 8, 3′, 4′ hydroxyl group, such as flavones (luteolin and 7, 8-dihydroxyflavone), flavonols (kaempferol and quercetin), flavanones (naringenin and eriodictyol), isoflavonoids (daidzein and glycetein), and caffeic acid as substrates, and 15 OMTs were proven to catalyze at least one substrate. The methylation activities of these GmOMTs covered the 3, 7, 8, 3′, 4′- hydroxyl of flavonoids and 7, 4′- hydroxyl of isoflavonoids. The systematic characterization of G. max flavonoid OMTs provides insights into the biosynthesis of methylated flavonoids in soybeans and OMT bioparts for the production of methylated flavonoids via synthetic biology.

Abstract Taxol is a widely-applied anticancer drug that inhibits microtubule dynamics in actively replicating cells. Although a minimum 19-step biosynthetic pathway has been proposed and 16 enzymes likely involved have been characterized, stepwise biosynthetic reactions from the well-characterized di-oxygenated taxoids to Taxol tetracyclic core skeleton are yet to be elucidated. Here, we uncover the biosynthetic pathways for a few tri-oxygenated taxoids via confirming the critical reaction order of the second and third hydroxylation steps, unearth a taxoid 9α-hydroxylase catalyzing the fourth hydroxylation, and identify CYP725A55 catalyzing the oxetane ester formation via a cascade oxidation-concerted acyl rearrangement mechanism. After identifying a acetyltransferase catalyzing the formation of C7-OAc, the pathway producing the highly-oxygenated 1β-dehydroxybaccatin VI with the Taxol tetracyclic core skeleton is elucidated and its complete biosynthesis from taxa-4(20),11(12)-diene-5α-ol is achieved in an engineered yeast. These systematic studies lay the foundation for the complete elucidation of the biosynthetic pathway of Taxol.

ObjectiveTo evaluate the exposure levels and health risks of aflatoxins （AFT） in dried chili and chili powder sold in Shandong Province.MethodsAFT in chili and chili powder samples were determined using liquid chromatography-triple quadrupole mass spectrometry， and aflatoxin exposure was calculated using the point evaluation method.ResultsThe detection rate of AFTB1 was the highest in the 120 samples of dried chili and chili powder investigated， at 21.7% （26/120）. The proportion of samples exceeding the national standard limit was 8.3% （10/120）； the qualification rate was 91.7% （110/120）. The detection rate of AFTB2 was 19.2% （23/120）， that of AFTG1 was 5.0% （6/120）， and that of AFTG2 was 0.8% （1/120）. The detection rate of AFT in chili powder was significantly higher than that of dry chili samples （P

The March 2021 dust storm in China degraded air quality across a wide area of Asia. Atmospheric circulation and meteorological factors play an important role in the occurrence of dust storms. To understand whether decreasing or increasing these factors can mitigate dust storms, this study utilizes remote sensing imagery data from the Himawari-8/-9 satellites to understand spatial and temporal variations in China’s 2016–2023 dust storms. Our findings are as follows: (1) in 2016–2023, dust storms covered northern China, with Xinjiang, Inner Mongolia, Gansu, and Ningxia being high-frequency areas; (2) the origins of the dust storms are northwest of Mongolia and Xinjiang, with upper air masses originating from Siberia and concentrating in central-west Inner Mongolia and northern Gansu; (3) dew point temperature, wind speed, cloud cover, and atmospheric circulation are important determinants of the occurrences of dust storms. Analyzing trends and influential factors of dust storms is important as this provides a scientific basis for decision-making in dust storm management.

Texture features play an important role in the field of remote sensing classification. However, most existing methods lack a comprehensive consideration of spatial continuity, which makes them either destroy the spatial integrity of regular ground objects or fail to quantify the fragmentation degrees of irregular ground objects. These problems weak the ability of existing methods to distinguish ground objects with different fragmentation degrees. Therefore, this study proposed a new texture feature extraction method considering spatial continuity and gray diversity (SCGD). SCGD first connected all pixels in a neighborhood in series from end to end according to the row and column directions, and the diversities of the spatial continuity encoding in different directions were calculated by the Shannon index. Then, the Shannon index was used to calculate the gray diversity. Finally, SCGD calculated the weighted average of spatial continuity diversity and gray diversity to obtain the final texture feature values. Validation results indicated that SCGD can effectively distinguish ground objects with different fragmentation degrees, and its performance is better than that of traditional methods. As the spatial resolution decreases, its performance advantage becomes more obvious. Moreover, SCGD has great application potential in the field of ground object classification, and combining it with deep learning models will contribute to achieving the fine recognition of ground objects.

Objective To summarize the clinical characteristics of children with functional neurological disorder (FND) presented with motor symptoms. Methods and Results Total 18 children with FND mainly manifested by motor symptoms were admitted to Department of Pediatrics in Peking University Third Hospital from July 2017 to June 2023. The clinical phenotypes included 8 cases of myoclonus, 3 of tremor, 3 of myasthenia, 2 of dystonia, and 2 of psychogenic non⁃epileptic seizure (PNES). There was no overlap of movement disorder symptoms in all patients. Of the 8 cases with clonus, 5 showed bilateral symmetry myoclonus, and 3 involved only the right upper limb or right hand. Three cases of tremor presented with rapid tremor on one or both upper limbs or hands. Three patients with myasthenia showed weakness of both lower limbs and inability to walk. Of the 2 patients with dystonia, one had paroxysmal upper limb and trunk torsion postural abnormalities, and one had intermittent muscle tone and hip flexion of the lower limb. Two cases of PNES were characterized by gaze, neck tilt, limb extension and flexion tremors, and tapping. One case had mild abnormal EEG and repeated small chromosome fragments. Tirteen cases had mild symptoms and good prognosis after treatment. Five cases with severe symptoms combined with mental symptoms were transferred to Department of Psychiatry for further treatment. Conclusions The most common manifestations of children with FND presented with motor symptoms are myoclonus, tremor and myasthenia, which can be traced to related causes, and may be accompanied by a variety of other physical or psychiatric symptoms. Some children need to be referred to Department of Psychiatric for further treatment.

Abstract Micro-gyroscopes using micro-electro-mechanical system (MEMS) and micro-opto-electro-mechanical system (MOEMS) are the new-generation and recently well-developed gyroscopes produced by the combinations of the traditional gyroscope technology and MEMS/MOEMS technologies. According to the working principle and used materials, the newly-reported micro-gyroscopes in recent years include the silicon-based micromechanical vibratory gyroscope, hemispherical resonant gyroscope, piezoelectric vibratory gyroscope, suspended rotor gyroscope, microfluidic gyroscope, optical gyroscope, and atomic gyroscope. According to different sensitive structures, the silicon-based micromechanical vibratory gyroscope can also be divided into double frame type, tuning fork type, vibrating ring type, and nested ring type. For those micro-gyroscopes, in recent years, many emerging techniques are proposed and developed to enhance different aspects of performances, such as the sensitivity, angle random walk (ARW), bias instability (BI), and bandwidth. Therefore, this paper will firstly review the main performances and applications of those newly-developed MEMS/MOEMS gyroscopes, then comprehensively summarize and analyze the latest research progress of the micro-gyroscopes mentioned above, and finally discuss the future development trends of MEMS/MOEMS gyroscopes.

Increasing the proportion of clean energy is an inevitable trend of high-quality energy development. While enjoying the benefits of clean energy, traditional fossil energy enterprises face great challenges. In this study, coal power and photovoltaic power are selected as examples for analysis. Considering coal consumption, carbon emission, unit ramp conditions and photovoltaic abandonment, a comprehensive income model containing thermal power and photovoltaic power generation is proposed. The objective function of maximizing earnings is established and solved by genetic algorithm. The results show that the overall benefit will increase if the proportion of photovoltaic does not increase blindly. The unreasonable ratio of thermal and photovoltaic power and the imbalance of supply and consumption will lead to the decline of economic benefits and the increase of coal consumption and carbon emission. In the case of a high proportion of clean energy penetration, on the one hand, traditional power plants should be responsible for ensuring the instability of electricity output when the photovoltaic is weak, on the other hand, they need to give up some of the supply proportion when clean power is at a high output state. Therefore, while increasing the proportion of clean energy, it is necessary to improve the speed of load adjustment, the depth of peak regulation and the efficiency of low load work in traditional power plants to ensure the healthy development of new energy.

In order to overcome the difficulty of gas mining when coal mining depth increased, the adsorption and diffusion laws of CO2 molecules at different temperatures and pressures were simulated by using the simulation software Materials Studio; the relationship between CO2 mean square displacement and time was simulated based on molecular dynamics. The results showed that in the isothermal adsorption curves of 15 ℃, 25 ℃, 30 ℃ and 35 ℃, the adsorption capacity of CO2 decreased gradually when temperature increased. It showed that CO2 was conducive to geological storage at low temperatures; the values of self-diffusion coefficient, corrected diffusion coefficient and transfer diffusion coefficient of CO2 in coal increased when temperature and pressure increased. The maximum value was reached at 35 ℃ and 3.5 MPa.

Quality makers (Q-markers) are pivotal for the standardization of quality control for traditional Chinese medicine (TCM) drugs. However, it’s a great challenge to identify the Q-markers of TCM drugs especially for TCM formulas. This study was designed to provide a method to discover Q-markers of TCM formulas and applied to identify the Q-markers responsible for the anti-cholestatic effect of Danning tablet (DNT), a TCM formulae consisting with seven herbal ingredients. In this study, the anti-cholestatic effect of DNT was evaluated in mice with cholestasis induced by α-naphthyl isothiocyanate (ANIT). An untargeted metabolomic profiling were performed using serum and liver samples of mice. Xenobiotics derived from DNT and endogenous compounds responsible for the anti-cholestatic effect of DNT were screened by statistical analysis and the Q-markers of DNT were illustrated, followed by predicting the potential targets and mechanisms via network pharmacology study. DNT exhibited a protective effect against liver injury in mice with ANIT-induced cholestasis. Three endogenous compounds, namely taurochenodeoxycholic acid (TCDCA), taurocholic acid (TCA), and glycocholic acid (GCA), were identified as the endogenous markers responsible for the anti-cholestatic effect of DNT. By setting a cutoff value of the correlation co-efficient at 0.8, 6 promising Q-markers, including luteolin, kaempferol, apigenin, emodin, luteolin-7-glucoside, and 5,4′-dihydroxy-3,6,7,8,3′-pentamethoxyflavone, were screened out. These Q-markers were stably existed in DNT and predicted to be highly active in treating cholestasis. This study established a pipeline to screen out the potential Q-markers of TCM formulas and 6 key Q-markers responsible for the anti-cholestatic effect of DNT were identified.

Enhancing the ability to manage abnormal situations is important for improvement of the safety of nuclear power plants. It is necessary to investigate potential risks thoroughly in advance, and prepare countermeasures against the identified risks. In addition, in case of an occurrence of an abnormal situation, plant operators are required to recognize the plant situation promptly and select a suitable countermeasure. However, the human ability to perform it is limited because the number of such abnormal situations in actual nuclear power plants is indefinite. Due to the advent of AI, it becomes possible to compensate for such limitation, by learning abnormal situations and assessing the effectiveness of prepared countermeasures virtually. The present study aims to develop such an AI-based support system for the plant operators to deal with abnormal situations steadily. Although many previous studies about detection of anomalies have been conducted, few studies consider countermeasures, especially against unexperienced abnormal situations. This study develops a novel plant operator support system designed not only to estimate details of anomalies in a plant but also propose countermeasures adaptively by employing several AI technologies of deep neural network and reinforcement learning. A plant simulator is used to prepare training data for the AI system. The combination of the proposed AI-based system and the plant simulator makes it possible to identify abnormal situations unknown to operators and propose countermeasures. The design and performance of the proposed system is illustrated using High Temperature engineering Test Reactor (HTTR) operated in Japan Atomic Energy Agency.

Four energetic binders, polyglycidyl nitrate (PGN), poly(3-nitratomethyl-3-methyloxetane) (PNIMMO), poly(bis(azidomethyl)oxetane) (PBAMO), and glycidyl azide polymer (GAP) were, respectively, mixed with dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50), forming TKX-50-based polymer bonded explosives (PBXs). Interfacial forces (binding energies) under different temperatures, mechanical properties (tensile modulus, bulk modulus, shear modulus, and Poisson’s ratio), and moldability of TKX-50-based PBXs were investigated by employing molecular dynamics simulation, the energy characteristics of TKX-50-based PBXs were calculated by Chapman–Jouguet (C–J) detonated theory. Results show that temperature has little effect on the binding energies, but the binding energies between every energetic binder and each surface of TKX-50 are different and the order of combined ability between four energetic binders and TKX-50 decrease as follows: PNIMMO > PBAMO > PGN > GAP. Compared with TKX-50, the addition of four energetic binders makes the rigidity of TKX-50-based PBXs decrease and the plasticity improve, the plastic ability rank is in the order of PGN > PNIMMO > PBAMO > GAP. In addition, the moldability of TKX-50-based PBXs is obviously improved, the increasing order is PGN > PNIMMO > PBAMO > GAP. Finally, the detonation performances indicate that compared with common binder, the addition of the energetic binder makes TKX-50-based PBXs have higher energy under the same condition.

Knowledge of forest management types is key to sustainable forest restoration practices, forest biomass assessment, and carbon accounting. However, there are no available global forest-management maps because of the spectral similarity of different forest management types. As such, we applied random forest and change detection algorithms to generate annual maps of 6 forest management types at a spatial resolution of 250 m from 2001 to 2020 including naturally regenerated forest (unmanaged and managed), planted forest (rotation of >15 years and ≤15 years), oil palm plantation, and agroforestry. In general, validation results on a point scale show that the overall accuracy is 86.82% ± 9.14%, indicating that our annual maps accurately represent global spatiotemporal variations in forest management types. Furthermore, we estimated the annual biomass carbon stock of different forest management types. The net expanded areas of planted forest, oil palm plantation, and agroforestry offset 59.56% of the loss of forest area and 77.13% of the loss of biomass carbon stock due to the decrease in the naturally regenerated forest. The decrease of managed natural regeneration forests, the expansion of planted forests with a rotation period of more than 15 years, and agroforestry resulted from reforestation practices, while the expansion of planted forests with a rotation period of less than 15 years and oil palm plantations resulted from the removal of part of agroforestry. Moreover, the expansion of planted forests with a rotation of less than 15 years (72.73%) dominates the global expansion of planted forests, and China has contributed 42.20% of this expansion. Our results are beneficial for nature solution-based climate change mitigation.

In this article, we study the sharp profiles of positive solutions to the diffusive logistic equation. By employing parameters and analyzing the corresponding perturbation equations, we find the effects of boundary and spatial heterogeneity on the positive solutions. The main results exhibit the sharp effects between boundary conditions and linear/nonlinear spatial heterogeneities on positive solutions.

Zea mays (maize) is an important agricultural crop that produces a variety of valuable terpenoids, including several triterpenoids. However, no oxidosqualene cyclase (OSC) enzymes, which catalyze the first step in triterpenoid biosynthesis, have been identified in maize. Here, we identified a novel OSC (ZmOSC1) in maize using a combination of genomic mining and phylogenetic analyses. To functionally characterize the candidate OSC, we constructed a yeast strain that produced high levels of 2,3-oxidosqualene. When ZmOSC1 was expressed in this strain, three compounds were detected and identified as hop-17(21)-en-3-ol, hopenol B and simiarenol, respectively. For their biosynthesis, we proposed a potential cyclization mechanism catalyzed by ZmOSC1 via the generation of a dammarenyl cation, followed by sequential cationic ring expansion, cyclization, cationic migration and further proton elimination. This study discovered and characterized an OSC from maize for the first time, and laid a foundation to produce three bioactive pentacyclic triterpenes, hop-17(21)-en-3-ol, hopenol B and simiarenol, using synthetic biology approaches.

To cope with the energy crisis and environmental degradation, the new energy represented by wind and photovoltaic power generations have developed rapidly, which leads to a large number of power electronic converters being connected to the power grid. In this context, the power-electronic-based power system has become a trend. However, when wideband impedance mismatch happens between the power electronic converter and the connected power supply network, the wideband oscillation will occur in the system, which seriously endangers the safe and stable operation of the power system. To solve it, impedance identification is a key step to obtain the dq-frame impedance characteristics to analyze the power system stability. This article focuses on the power supply network and proposes an improved method to identify its dq-frame wide-band impedance by only one disturbance, which greatly simplifies the dq-frame wideband impedance identification process to improve the identification efficiency. It is of great significance for the safe and stable operation of the power-electronic-based power system.

Machine learning methods have been recognized as rapid methods for satellite-based aerosol retrievals but have not been widely applied in geostationary satellites. In this study, we developed a wide and deep learning model to retrieve the aerosol optical depth (AOD) using Himawari-8. Compared to traditional deep learning methods, we embedded a “wide” modeling component and tested the proposed model across China using independent training (2016–2018) and test (2019) datasets. The results showed that the “wide” model improves the accuracy and enhances model interpretability. The estimates exhibited better accuracy (R2 = 0.81, root-mean-square errors (RMSEs) = 0.19, and within the estimated error (EE) = 63%) than those of the deep-only models (R2 = 0.78, RMSE = 0.21, within the EE = 58%). In comparison with extreme gradient boosting (XGBoost) and Himawari-8 V2.1 AOD products, there were also significant improvements. In addition to higher accuracy, the interpretability of the proposed model was superior to that of the deep-only model. Compared with other seasons, higher contributions of spring to the AOD concentrations were interpreted. Based on the application of the wide and deep learning model, the near-real-time variation of the AOD over China could be captured with an ultrafine temporal resolution.

Micro-gyroscopes based on the Coriolis principle are widely employed in inertial navigation, motion control, and vibration analysis applications. Conventional micro-gyroscopes often exhibit limitations, including elevated noise levels and suboptimal performance metrics. Conversely, the advent of cavity optomechanical system technology heralds an innovative approach to micro-gyroscope development. This method enhances the device’s capabilities, offering elevated sensitivity, augmented precision, and superior resolution. This paper presents our main contributions which include a novel dual-frame optomechanical gyroscope, a unique photonic crystal cavity design, and advanced numerical simulation and optimization methods. The proposed design utilizes an optical cavity formed between dual oscillating frames, whereby input rotation induces a measurable phase shift via optomechanical coupling. Actuation of the frames is achieved electrostatically via an interdigitated comb-drive design. Through theoretical modeling based on cavity optomechanics and finite element simulation, the operating principle and performance parameters are evaluated in detail. The results indicate an expected angular rate sensitivity of 22.8 mV/°/s and an angle random walk of 7.1 × 10−5 °/h1/2, representing superior precision to existing micro-electromechanical systems gyroscopes of comparable scale. Detailed analysis of the optomechanical transduction mechanism suggests this dual-frame approach could enable angular vibration detection with resolution exceeding state-of-the-art solutions.

A key missing enzyme in the plant Panax ginseng Rg2 and Re2 ginsenoside biosynthesis pathway is identified, and its expression is engineered in yeast for high-level production.

Lake nitrogen (N) removal, mainly resulting from bacterial denitrification that converts nitrate (NO _3 ^− ) to gaseous N (N _2 ), is important for lake water quality and eutrophication control. However, quantifying lake N removal is challenging due to the high background atmosphere N _2 concentration and the heavy burden of field surveys, leading to a decoupling of watershed N management and water quality improvement. Here, we developed and validated an innovative nonlinear model for lake N removal rate estimation by linking the N removal rates with remote sensing-derived variables (chlorophyll- a , chromophoric dissolved organic matter, and lake surface water temperature). The model was validated in shallow eutrophic Lake Taihu in the Yangtze River basin and at the global scale. Based on the new N removal model, we estimated that an annual average of 3.21 × 10 ^4 t N yr ^‒1 was removed in Lake Taihu from 2011 to 2020, accounting for 53%–66% of the total lake N loading. The remaining N loading after denitrification removal in Lake Taihu would be approximately 2.37 mg N l ^‒1 , and 0.79 × 10 ^4 t N y ^‒1 of lake N loading still needs to be removed to meet the target of class IV water quality (1.5 mg N l ^‒1 ). This is the first study linking lake N removal in sediment microcosm incubations with reach-scale remote sensing derived variables, providing timely-much insights into lake N removal. This approach can be easily applied in other lakes with satellite derived data, to better understand lake N budget, drivers of eutrophication control, and watershed N management.

In the twentieth century, China underwent huge social transformations, probably with equally great changes in education. Under the influence of the influx of Western learning in this period, traditional education models were challenged, and new schools, together with new educational concepts, started to come into being. Inside this process, the roles and images of intellectuals changed a lot as keen observers and active participants in social change. The paper compares two representative figures, Mr. Zhu from White Deer Plain and Ni Huanzhi from Ni Huanzhi, in efforts to comprehend the intellectuals in their various roles within the context of contemporary Chinese educational reforms. Mr. Zhu was a protector and promoter of traditional culture and thoughts, while Ni Huanzhi was an advocate for new cultures and ideas. Their divergent paths, and different roles in society, have been carved out by different life experiences. This paper also explores differences in positions in educational reforms, contributions toward educational progress, and strategies in the face of social changes. The significance of these preceding analyses is to assess their historical value with a view to drawing reflective lessons and insights that would enlighten contemporary educators.

Phytase efficiently hydrolyzes phytate to phosphate; thus, it is widely used to increase phosphorus availability in animal feeds and reduce phosphorus pollution through excretion. Phytase is easily inactivated during feed pelleting at high temperature, and sufficient thermostability of phytase is essential for industrial applications. In this study, directed evolution was performed to enhance phytase thermostability. Variants were initially expressed in Escherichia coli BL21 for screening, then in Pichia pastoris for characterization. Over 19,000 clones were generated from an error-prone Polymerase Chain Reaction (epPCR) library; 5 mutants (G10, D7, E3, F8, and F9) were obtained with approximately 9.6%, 10.6%, 11.5%, 11.6%, and 12.2% higher residual activities than the parent after treatment at 99°C for 60 min. Three of these mutants, D7, E3, and F8, exhibited 79.8%, 73.2%, and 92.6% increases in catalytic efficiency (kcat/Km), respectively. In addition, the specific activities of D7, E3, and F8 were 2.33-, 1.98-, and 2.02-fold higher than parental phytase; they were also higher than the activities of all known thermostable phytases. Sequence analysis revealed that all mutants were substituted at residue 75 and was confirmed that the substitution of cysteine at position 75 was the main contribution to the improvement of thermostability of mutants by saturation mutagenesis, indicating that this amino acid is crucial for the stability and catalytic efficiency of phytase. Docking structure analysis revealed that substitution of the C75 residue allowed the mutants to form additional hydrogen bonds in the active pocket, thereby facilitating binding to the substrate. In addition, we confirmed that the intrinsic C77-C108 disulfide bond in E. coli phytase is detrimental to its stability.

With the continuous expansion of the power system scale, the requirements of the power system intelligence are getting higher and higher and the power grid fault diagnosis has been made to become the focus of the power system research. In this paper, the research field of power grid fault diagnosis is reviewed, and the data sources and characteristics and data preprocessing are analyzed. Moreover, the diagnosis mechanism, characteristics and deficiencies of various fault diagnosis methods, the improvement results and future research direction are reviewed in recent years, and the design of online diagnosis system architecture mode are established. A new type of power system fault monitoring and networking method is proposed which is more concise and reliable than the traditional scheme. The power system fault diagnosis strategy based on knowledge representation and the fault diagnosis model with distributed architecture is structured which showed the efficiency is effectively improved. Finally, the problems faced by the power system fault diagnosis under the background of regulatory big data are discussed, and the development direction of the power grid fault diagnosis under this new situation is deeply analyzed.

Objective To evaluate the immunogenicity, safety and lot-to-lot consistency of an inactivated enterovirus 71 (EV71) vaccine cultured in bioreactors with different specifications after full immunization. Methods A randomized, double-blind trial was performed in 3,000 children aged 6 ~ 35 months with six vaccine batches, which were prepared in 40 L and 150 L bioreactors for three consecutive batches respectively. Children were immunized on day 0 and 28, serum samples were collected on day 0 and 56, and neutralizing antibody titers were determined by the microcytopathic method. Immediate reactions were recorded within 30 min, local and systemic symptoms were recorded within 0 ~ 28 days, and serious adverse events were recorded within 6 months. Results After immunization with two doses of the inactivated EV71 vaccine, the neutralizing antibody GMT was 825.52 ± 4.09, and the positive conversion rate was 96.18%, with no significant difference. The 95% CI of the serum neutralizing antibody GMT ratio between the two groups after immunization with the three vaccine batches produced in the 150 L and 40 L bioreactors ranged from .67 ~ 1.5. The overall incidence of adverse reactions, mainly grade 1 reactions, for all 6 batches from 0 to 28 days after vaccination was 49.62%, with no significant difference (p = .8736). The incidence of systemic adverse reactions, primarily fever and diarrhea, was 45.14%; the incidence of local adverse reactions, primarily erythema and tenderness, was 9.43%. Conclusion The EV71 vaccine was highly immunogenic and safe in children aged 6–35 months, and 6 consecutive batches produced by the two bioreactors with different specifications were consistent.

Abstract Background This study was to evaluate the diagnostic significance of Magnetic Resonance Imaging (MRI) in distinguishing temporomandibular disorders (TMD). Methods A total of 684 patients with TMD were included in the study. Diagnosis for TMD was conducted according to the international criteria. Two professional radiologists were selected for professional training, and the Kappa values were compared for the diagnosis results to determine the consistency of the diagnosis. Then MRI images of these 684 patients were analyzed and the diagnosis results were obtained. Results MRI can be used for the diagnosis of TMD. There were significantly more females (518 cases) than males (166 cases) with TMD; Disc displacement with/without reduction is more common in the youth group, with the majority aged 20–30 years. The highest incidence of temporomandibular joint osteoarthrosis is in the 60-year-old age group, followed by the 70-year-old age group. Conclusions Bilateral temporomandibular joint MRI can clearly show their changes; there are significantly more female with TMD than male; osteoarthritis has a significant correlation with age.

C64H44Br4N8O8Zn2, monoclinic, P21/c (No. 14), a = 6.6263(5) Å, b = 24.355(2) Å, c = 18.2418(15) Å, β = 96.433(2)°, V = 2925.4(4) Å3, Z = 2, Rgt(F) = 0.0400, wRref(F2) = 0.1302, T = 296(2) K.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), represents a significant global human health threat. The most effective way to end the pandemic is through timely vaccination. In this study, the receptor-binding domains (RBDs) of Spike protein of the initial strain of SARS-CoV-2 and its variants, B.1.1.7 (Alpha), B.1.351 (Beta), and B.1.617.1 (Kappa), were successfully displayed on the surface of a Saccharomyces cerevisiae strain for development as a vaccine candidate. To rapidly express the recombinant protein and avoid the need for expensive galactose as an inducer, the gal80 gene of S. cerevisiae was knocked out, and the conventional 72-h culture period was thus successfully shortened to 24 h. Mice vaccinated against variant B.1.617.1 showed robust humoral and cellular immune responses. Moreover, the antiserum in the B.1.671.1 group had neutralizing activity against wild-type RBD and high binding titers against RBD mutants of variants B.1.351 and B.1.1.7. Double deglycosylation at N331Q and N343Q resulted in marked reduction of the affinity of RBD binding to angiotensin converting enzyme 2 (ACE2) and escaped antibody neutralization. This study demonstrates that yeast surface display technology can provide an alternative approach to rapid large-scale preparation of promising SARS-CoV-2 vaccine candidates at low cost.

Ginsenoside Compound K (CK) has been recognized as a major functional component that is absorbed into the systemic circulation after oral administration of ginseng. CK demonstrates diverse bioactivities. A phase I clinical study indicated that CK was a potential candidate for arthritis therapy. However, a phase II clinical study was suspended because of the high cost associated with the present CK manufacturing approach, which is based on the traditional planting-extracting-biotransforming process. We previously elucidated the complete CK biosynthetic pathway and realized for the first time de novo biosynthesis of CK from glucose by engineered yeast. However, CK production was not sufficient for industrial application. Here, we systematically engineered Saccharomyces cerevisiae to achieve high titer production of CK from glucose using a previously constructed protopanaxadiol (PPD)-producing chassis, optimizing UGTPg1 expression, improving UDP-glucose biosynthesis, and tuning down UDP-glucose consumption. Our final engineered yeast strain produced CK with a titer of 5.74 g/L in fed-batch fermentation, which represents the highest CK production in microbes reported to date. Once scaled-up, this high titer de novo microbial biosynthesis platform will enable a robust and stable supply of CK, thus facilitating study and medical application of CK.

The intermittency and unpredictability are the obstacles to absorb all wind power. The combined heat and power (CHP) system has been widely utilized as a heat and electricity source, and the heating load limits the regulatory capacity of CHP to reduce curtailed wind power. This study proposes an optimization model of an integrated power and heating network system to fully utilize curtailed wind power. The thermal inertia in the primary heating network, thermal comfort of end-users, and electric boiler in the secondary heating network are included in multiple scenarios to analyze different operation strategies. The simulation results show that considering the heating network, the inertia and thermal comfort of end-users could reduce the curtailed wind power ratio from 15% to 9%. Adding a peak-shaving electric boiler on the user side can increase the system electric load and reduce the curtailed wind power, while reducing the heat output of the CHP unit during the peak and low periods of the heat load at night. Moreover, there is less than 1% of the curtailed wind power ratio if the peak-shaving capacity ratio is higher than 10%, which means the application recommendations of installed electric boiler capacity are obtained to increase enough flexibility of the power and heating network system.

The Xinfengjiang reservoir in Guangdong Province, is one of the large reservoirs that have triggered earthquakes of magnitude greater than 6. Numerous earthquakes have occurred since the impoundment of the reservoir, making it one of the most active seismic zones in south China. In 2015, a set of deep-hole resistivity anomalies was observed in the Heping geoelectric station in Dongyuan county, located near the Xinfengjiang reservoir. After a field investigation, we found that a planned well drilling construction of new measuring channels was being carried out during that corresponding period of time. After careful comparison and analysis on the basis of the collected raw data, we had a reason to believe that drilling construction, rather than the inducement of the Xinfengjiang reservoir, was the main culprit for those unusual georesistivity values. So as to verify the above conjecture, we constructed a series of 3D finite element models based on the geological and hydrological information around Heping station and analyzed the drilling disturbances, respectively. Some significant conclusions were finally drawn according to the precise numerical simulation. This study gives a good example by combining numerical simulation with engineering practice as a way to understand the root cause of georesistivity anomalies in reality.

Lung cancer is one of the most fatal malignant tumors in the world. Overcoming this disease is difficult due to its late diagnosis and relapse after treatment. Minimal residual disease (MRD) is described as the presence of free circulating tumor cells or other tumor cell derivatives in the biological fluid of patients without any clinical symptoms of cancer and negative imaging examination after the treatment of primary tumors. It has been widely discussed in the medical community as a bridge to solid tumor recurrence. Radiology, serology (carcinoembryonic antigen), and other clinical diagnosis and treatment methods widely used to monitor the progression of disease recurrence have obvious time-limited and -specific defects. Furthermore, as most samples of traditional liquid biopsies come from patients’ blood (including plasma and serum), the low concentration of tumor markers in blood samples limits the ability of these liquid biopsies in the early detection of cancer recurrence. The use of non-blood-derived fluid biopsy in monitoring the status of MRD and further improving the postoperative individualized treatment of patients with lung cancer is gradually ushering in the dawn of hope. This paper reviews the progress of several non-blood-derived fluid samples (urine, saliva, sputum, and pleural effusion) in detecting MRD in lung cancer as well as selecting the accurate treatment for it.

BACKGROUND China is the largest importer of copper concentrate in the world. Studying the mineralogical characteristics of copper concentrates imported from different origins can be used to support the origin analysis and solid waste identification of copper concentrates. OBJECTIVES To investigate the elemental composition and mineral assemblage characteristics of imported copper concentrates from different mining areas, and to discuss the mineralogical differences of copper concentrates of different genetic types. METHODS The copper concentrates imported from different mining areas were comprehensively analyzed by X-ray fluorescence spectrometry (XRF), X-ray powder diffraction (XRD) and polarized microscopy (PM). RESULTS X-ray fluorescence spectroscopy analysis showed that the main elements of the copper concentrates were Cu, Fe, S, O with minor Zn, Si, Al, Mg, Ca, Pb. X-ray powder diffraction phase analysis showed that the main phase of the copper concentrate sample was chalcopyrite, followed by pyrite and sphalerite. Polarization microscope showed that the content of chalcopyrite in copper concentrates was between 88% and 98%, and it was found that chalcopyrite was associated with sphalerite, pyrite and pyrrhotite, and that sphalerite was associated with bornite, arsenotetrahedrite. Chalcopyrite, arsenotetrahedrite and bornite form intergrowths. Combining the analysis of different genetic types of copper concentrates, samples of porphyry, skarn and VMS deposits were composed of chalcopyrite, pyrite and sphalerite with respective special minerals of biotite, weddellite and lead anglesite. The main minerals of the IOCG deposit samples were chalcopyrite, pyrrhotite and talc. CONCLUSIONS Through the combination of XRF, XRD and PM, the elemental content and phase composition of copper concentrate samples were characterized. The mineralogical characteristics of copper concentrate samples from different origins have been more comprehensively analyzed, which is of great significance for risk identification and control of imported copper concentrates.

The non-isothermal reaction kinetics of cyanate ester system was investigated by dynamic differential scanning calorimetry (DSC). The analysis of non-isothermal data was carried out by using the model-fitting Kissinger, Flynn-Wall-Ozawa, and Crane methods. The results indicate that the apparent activation energy of the curing reaction is 101.3 kJ·mol-1 and 99.4 kJ·mol-1calculated from Kissinger and Flynn-Wall-Ozawa models, respectively. The reaction sequence of the adhesive is 0.92 calculated from Crane model. In addition, the relationship of the curing degree with the curing temperature and the curing time is established. The curing parameters are obtained by adopting "T-β" and "t-β" extrapolation, and the strength test proves the validity of the curing parameters designed in this paper. These results constitute a theoretical basis for the curing and application of the cyanate ester adhesives.

Gut microbiota plays an important role in metabolic homeostasis. Previous studies demonstrated that ginsenoside Rb1 might improve obesity-induced metabolic disorders through regulating glucose and lipid metabolism in the liver and adipose tissues. Due to low bioavailability and enrichment in the intestinal tract of Rb1, we hypothesized that modulation of the gut microbiota might account for its pharmacological effects as well. Here, we show that oral administration of Rb1 significantly decreased serum LDL-c, TG, insulin, and insulin resistance index (HOMA-IR) in mice with a high-fat diet (HFD). Dynamic profiling of the gut microbiota showed that this metabolic improvement was accompanied by restoring of relative abundance of some key bacterial genera. In addition, the free fatty acids profiles in feces were significantly different between the HFD-fed mice with or without Rb1. The content of eight long-chain fatty acids (LCFAs) was significantly increased in mice with Rb1, which was positively correlated with the increase of Akkermansia and Parasuttereller, and negatively correlated with the decrease of Oscillibacter and Intestinimonas. Among these eight increased LCFAs, eicosapentaenoic acid (EPA), octadecenoic acids, and myristic acid were positively correlated with metabolic improvement. Furthermore, the colonic expression of the free fatty acid receptors 4 (Ffar4) gene was significantly upregulated after Rb1 treatment, in response to a notable increase of LCFA in feces. These findings suggested that Rb1 likely modulated the gut microbiota and intestinal free fatty acids profiles, which should be beneficial for the improvement of metabolic disorders in HFD-fed mice. This study provides a novel mechanism of Rb1 for the treatment of metabolic disorders induced by obesity, which may provide a therapeutic avenue for the development of new nutraceutical-based remedies for treating metabolic diseases, such as hyperlipidemia, insulin resistance, and type 2 diabetes.

Objective This study aimed to investigate health-promoting lifestyle status and associated risk factors in patients with polycystic ovary syndrome (PCOS).Design Cross-sectional study.Setting This study was conducted at a tertiary hospital in Guizhou, China from December 2020 to June 2021.Participants A total of 366 participants (18–45 years) diagnosed with PCOS were recruited from the outpatient departments.Measures Sociodemographic characteristics were collected, and health-promoting behaviours were measured using the Health-Promoting Lifestyle Profile scale. Anxiety status was measured using the Zung’s Self-Rating Anxiety Scale, depression status using the Zung’s Self-Rating Depression Scale and self-efficacy using the Managing Chronic Disease 6-Item Scale. Multiple stepwise linear regression was conducted to assess the risk factors associated with the health-promoting behaviours of the study participants.Results The participants had a poor health-promoting behaviours (88.54±17.44). The highest score in all dimensions was spiritual growth (16.68±4.98), while physical activity (12.71±2.68) was the lowest. Multiple regression analysis revealed that the main factors influencing the development and maintenance of health-promoting behaviours among participants were education (B=10.788, p

Tree-based machine learning and deep learning approaches are widely applied in ozone (O3) retrieval, but they cannot achieve high accuracy and interpretability simultaneously. To overcome this limitation, a tree-based ensemble deep learning model, named semi-SILDM, was proposed for O3 prediction at both national (5 km) and urban scales (250 m) in China. The Moderate Resolution Imaging Spectroradiometer (MODIS) Top of Atmosphere (TOA) measurements were first investigated through significant linear and nonlinear relationships with surface O3. To examine the actual predictive ability of the semi-SIDLM, time-based validation was employed to divide data chronologically by year into training (2018), validation (2017), and test data (2019). The semi-SIDLM predicted O3 in 2019 showed a coefficient of determination (R2) of 0.71 (0.69) and a Root Mean Square Error (RMSE) of 21.88 (26.59) µg/m3 at the national (urban) scale in China. In addition to its high accuracy, the semi-SIDLM has interpretability for retrieval results, which indicates the strong influence of the Fangshan and Tongzhou districts on the principle O3 Beijing urban area; the temporal characteristics reveal the higher contributions of May–July to O3 pollution compared to other months. The proposed model of this study will benefit further studies on O3 monitoring and deepen the understanding of its spatiotemporal characteristics.

Growing demand for water desalination promoted the vigorous development of reverse osmosis (RO) membrane. How to effectively remove boron from seawater is the key problem to be solved by RO membrane. It is important to select suitable membrane materials for experimental design before complicated and expensive experimental attempts. In this paper, we demonstrate that pore chemistry plays a key role in boron removal capability of RO membranes via nonequilibrium molecular dynamics simulations. This study shows that the introduction of hydroxyl (-OH) groups into the Covalent organic frameworks (COFs) pore allows for better boron removal without changing water permeability. The optimal boron rejection of AB-COF membranes is 76.67%, and that of ATFG-COF membranes with hydroxyl groups can achieve 90%. This is caused by the hydrophilic pore of ATFG-COF that will preferentially adsorb water molecules to prevent the passage of boric acid molecules through membrane zone. Additionally, -OH groups on the pore will also adsorb a part of boric acid in the membranes, reducing the amount of boric acid entering into the permeate side. The results obtained in this paper can provide guidance for the rational design of RO membranes to achieve more efficient boron removal.

C13H9ClO2, monoclinic, P21 (No. 4), a = 6.5465(9) Å, b = 8.0647(11) Å, c = 10.8476(15) Å, β = 105.591(3)°, V = 551.63(13) Å3, Z = 2, Rgt(F) = 0.0532, wRref(F2) = 0.1507, T = 296(2) K.

Al0.4FeCrCo1.5NiTi0.3 high-entropy alloy (HEA) was prepared by mechanical alloying (MA) and spark plasma sintering (SPS), which were evaluated in this study by XRD and TEM. After SPS, the bulk alloy exhibited a structure with a dominant fcc phase, a minor volume fraction of bcc phase, and the formation of TiAl3 intermetallic compound. Deformation twinning was observed in the fcc phase in the bulk HEA. The latter had a compressive strength, strain and Vickers hardness of 2225 ± 15 MPa, 17.52 ± 0.50 % and 515 ± 16 HV, respectively. The corrosion resistance studies indicated that Al0.4FeCrCo1.5NiTi0.3 with ultra-fine grained micro-structure was easier to passivate and possessed excellent corrosion resistance. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.19452

Transportation-disadvantaged populations often face significant challenges in meeting their basic travel needs. Microtransit, a technology-enabled transit mobility solution, has the potential to address these issues by providing on-demand, affordable, and flexible services with multi-passenger vehicles. The ways in which microtransit supports underserved populations and the factors influencing its adoption are not well-studied, however. This research examines SmaRT Ride, a microtransit pilot program in the Sacramento, California, area operated by Sacramento Regional Transit. The project evaluates a broad range of factors influencing microtransit adoption and travel behavior among underserved populations using original revealed choice survey data collected from February – May 2024 with online and intercept surveys. A descriptive analysis revealed that SmaRT Ride has improved transportation access for these communities, complements the transit system by connecting fixed-route transit, and offers a cost-effective alternative to other transportation modes. A binary logistic regression was employed to explore differences between microtransit users and non-users with microtransit awareness. The results indicate that homeownership, employment status, frequency of public transit service use, and attitude towards transit significantly affect microtransit use. Homeowners are more likely to use microtransit, while households without employed members are less likely. In contrast, part-time employees show a higher inclination to use microtransit. Regular public transit users are also more likely to incorporate microtransit into their routines, with a positive attitude toward public transit further increasing the likelihood of its use. The nuanced understanding of microtransit adoption presented here can inform targeted strategies to promote its use among transportation-disadvantaged groups. The results suggest that integrating microtransit with existing transit, outreach programs, discounted or free access, extended service hours, and supporting homeownership and affordable housing in transit-rich areas can encourage microtransit adoption by low-income and/or underserved individuals. View the NCST Project Webpage

Microtransit is a mobility service that dynamically routes and schedules 6- to 20-seat vehicles to serve passengers within a defined region. Microtransit services are similar to ride-pooling services operated by Transportation Network Companies (e.g., Uber, Lyft); however, microtransit services are owned by cities or transit agencies. Integrating microtransit services with traditional fixed-route transit (FRT) has been touted as a means to attract more riders to public transit generally, improve mobility and sustainable transportation outcomes (e.g., reduce greenhouse gasses and local pollutants), and provide better accessibility to disadvantaged travelers. However, few academic studies have evaluated these claims. To address this gap, we surveyed California transit agencies that currently operate or recently operated microtransit services to obtain insights into integration challenges. We also developed an agent- and simulation-based modeling framework to evaluate alternative system designs for integrating FRT and microtransit in downtown San Diego and Lemon Grove, a suburban area in San Diego County.