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Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, continues to mutate and generates new variants with increasingly severe immune escape, urging the upgrade of COVID-19 vaccines. Here, based on a similar dimeric RBD design as our previous ZF2001 vaccine, we developed a novel broad-spectrum COVID-19 mRNA vaccine, SWIM516, with chimeric Delta-BA.2 RBD dimer delivered by lipopolyplex (LPP). Unlike the popular lipid nanoparticle (LNP), this LPP-delivered mRNA expresses only in the injection site, which avoids potential toxicity to the liver. We demonstrated the broad-spectrum humoral and cellular immunogenicity of this vaccine to Delta and Omicron sub-variants in naïve mice and as booster shots. When challenged with Delta or Omicron live virus, vaccinated hACE2 transgenic mice and rhesus macaques were both protected, displaying significantly reduced viral loads and markedly relieved pathological damages. We believe the SWIM516 vaccine qualifies as a candidate for the next-generation broad-spectrum COVID-19 vaccine. Author summary: mRNA vaccines have demonstrated their advantages in immunogenicity and development speed during the coronavirus disease 2019 (COVID-19) pandemic. However, the significant immune escape caused by the evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has presented a considerable challenge to the effectiveness of COVID-19 vaccines. Moreover, concerns have arisen about the potential liver toxicity associated with the lipid nanoparticles (LNP) used in approved mRNA vaccines, raising questions about their safety. To address these challenges, we have developed the SWIM516 vaccine, which utilizes a chimeric Delta-BA.2 RBD dimer immunogen to provide broad-spectrum protection and a lipopolyplex (LPP) delivery system to enhance safety. This vaccine has demonstrated its ability to induce broad-spectrum immunogenicity in mice and offers protection to both mice and monkeys when exposed to live SARS-CoV-2 challenges, qualifying it as a next-generation broad-spectrum COVID-19 vaccine. [ABSTRACT FROM AUTHOR]

Based on the actual operation scenario of metro, this paper proposes an uneven parameter stray current distribution model. The model combines the calculation method of multi-section traction power supply of metro and establishes an uneven parameter stray current distribution model in different calculation domains with the metro operation position and the traction substation position as the boundary points. The improved dynamic boundary conditions were used to calculate the model. Compared with the experimental data, the average maximum deviation between the two was 0.677. Meanwhile, the dynamic space–time distribution characteristics of stray current and the change law of rail-to-ground voltage were obtained through simulation analysis. In addition, the calculation model for ground potential gradient distribution under stray current interference was established by discretizing stray currents within each calculation domain, and the characteristics of ground potential gradient distribution were simulated and analyzed. The results showed that the distribution period of stray current was approximately equal to the headway, and the waveform change lagged behind the rail-to-ground voltage. The fluctuation degree of ground potential gradient was obviously affected by the length of power supply interval and train operation conditions. [ABSTRACT FROM AUTHOR]

Peatlands are important carbon pools and stable carbon sinks in terrestrial ecosystems. Studying carbon storage and accumulation characteristics can provide a scientific basis for the conservation and restoration of peatlands. Based on the 2014–2015 survey of the Jilin Provincial Forestry Department on the carbon storage of peatlands in the Changbai Mountains, the surveyed 865 peatlands have a total area of 22,900 hm2 and carbon storage of 18,753,300 tons. There are 275 medium‐sized organic carbon (OC) stocks of peatlands (10000–100,000 tons) in this area, and their carbon storage accounts for 41.3% of the total reserves. The peatland carbon in this area is mainly distributed in the Yanbian Korean Autonomous Prefecture, valleys and the lava platform are the most important geomorphological basis for peatland deposits. The Mudanjiang River Basin has the largest carbon storage and it is dominated by a nutrient‐rich peatland. Peatlands in the Changbai Mountains formed and developed since the Holocene, and the carbon accumulation intensity is different in each stage. The average carbon density of peatlands in this area was 69.74 kg/m3 with an average value of 81.77 kg/m2 for OC accumulation per unit area. The average value of the carbon cumulative intensity of peatlands was 164.43 ton/km2 and the carbon accumulation rate of peatlands was 38.96 g/(a m2). [ABSTRACT FROM AUTHOR]

Clothing-based respiratory monitoring can provide real-time non-invasive respiratory monitoring services for subjects, and can be used as a reference for daily health observation. In this study, an optical fiber sensing Section woven into plain fabric is produced by a hand-weaving machine, and the produced sensing fabric is then made into a respiratory monitoring garment. This paper explored the luminescence and coupling principle of notched optical fiber through theoretical analysis and simulation, and demonstrated the feasibility of making it into respiratory sensing fabric. We used this structure to make a fabric and then sew the fabric with the yoke to make a smart garment. In testing, we obtained the static respiratory waveform and the respiratory rate (R-R) during daily common movements, which were also compared with two types of commercial sensors. The results showed that the smart garment based on optical fiber sensing fabric maintains good consistency with the monitoring waveform of commercial sensors and good R-R obtained in static motion (error not more than 2 rpm). Monitoring tests showed that the garment has high monitoring accuracy and motion monitoring stability. Moreover, it was also very comfortable and can be used as daily respiratory monitoring equipment. [ABSTRACT FROM AUTHOR]

Loss‐of‐control effectiveness is a common fault in the engineering field. In the existing adaptive fault‐tolerant control algorithms, observers and Lyapunov functions are often used to estimate fault parameters. However, they can only ensure the convergence of fault parameters as time goes to infinity. This leads to the fact that the controller can only play a better fault‐tolerant role in the steady‐state process, and cannot guarantee the system performance in the transient state. Therefore, a dual fault‐tolerant control (DFTC) algorithm is proposed for a class of stochastic systems with partial loss‐of‐control effectiveness. The algorithm introduces a fault‐tolerant objective on the basis of the control objective. By establishing a new objective function, the controller is forced to have the characteristics of active learning to improve the transient performance of the fault system. An example simulation verifies the validity of DFTC. The simulation results show that DFTC can drive the system to the desired output, especially when partial loss‐of‐control efficiency occurs in the system, it can learn the unknown parameters actively, quickly, and accurately, which is significantly better than the conventional control based on the certainty equivalence principle and improves the reliability of the system. [ABSTRACT FROM AUTHOR]

The selective detection of toxic Hg(II) ions is of great significance for industrial processing and environmental remediation. Herein, a novel copper(I) metal–organic framework [Cu3Cl3(bimpy)3] (1) (bimpy = 3,5-bis(1-imidazolyl)pyridine) was constructed by a solvothermal method. Single-crystal X-ray analysis shows that complex 1 is a 2-fold interpenetrated three-dimensional structure with a tfj topology, exhibiting high thermal stability and water stability. Complex 1 was used to modify a glassy carbon electrode (GCE) for the determination of Hg(II) in 0.1 M phosphate buffer solution (PBS) at pH = 7.0. However, on account of the poor electron-conductive property of complex 1, acetylene black (AB) was introduced into complex 1 to improve its electrochemical sensing activity. The electrochemical sensing property of AB and the complex 1 modified GCE was investigated by cyclic voltammetry and chronoamperometric tests. Under the optimal conditions, AB/complex 1/GCE exhibits a high sensitivity of 16.85 μA μM−1 cm−2 and a low limit of detection of 1.01 nM in the wide linear range from 2.0 μM to 64 μM. AB/complex 1/GCE could also be applied for detecting Hg(II) ions in tap water and river water. The aptasensor provides a valuable tool with satisfactory anti-interference, reproducibility, repeatability, simple preparation, and satisfactory applicability for the sensing of Hg(II) ions. [ABSTRACT FROM AUTHOR]

As an important biomarker, the level of reduced glutathione in serum is vital for human health. A novel 3D metal–organic framework with excellent photoluminescence properties, formulated as [Zn3(TNB)(DPE)2]·2H2O·DMF (1) (H3TNB = 4,4′,4′′-nitrilotribenzoic acid and DPE = 1,2-di(4-pyridyl)ethylene), was constructed by a solvothermal reaction. Complex 1 exhibits high water stability and pH stability in aqueous solution. It can detect Fe3+ and Pb2+ as a "turn-off" fluorescent probe in PBS solution with high sensitivity and selectivity. The detection limits for Fe3+ and Pb2+ are about 3.40 × 10−7 M and 4.59 × 10−7 M, respectively. Compared to Pb2+, Fe3+ has stronger oxidizability, and can be reduced to Fe2+ with the addition of a reductant, causing the fluorescence intensity of the Fe3+@1 system to significantly recover while that of the Pb2+@1 system has little change. Thus, the Fe3+@1 system exhibits a fluorescence "turn-on" signal after adding reduced glutathione (GSH) due to the reduction reaction, which indicates that complex 1 can be designed as an "on–off–on" fluorescent probe to detect Fe3+ ions and reduced GSH. The mechanism for fluorescence recovery is the elimination of the FRET process between Fe3+ and complex 1. In view of this reversible detection event, a two-input molecular logic gate was constructed. In addition, the "on–off–on" fluorescent sensor can be successfully applied to detection of reduced GSH in serum and fruits and vegetables with a high recovery range and low relative standard deviations (RSDs). To the best of our knowledge, this is the first example of a MOF-based probe for reduced GSH recognition by fluorescence "on–off–on" in PBS solution. [ABSTRACT FROM AUTHOR]

The large-scale use of pesticides such as organophosphate pesticides (OPPs) and organochlorine pesticides (OCPs) has led to serious environmental problems worldwide, and their high toxicity could cause serious damage to human health. It is crucial to remove and track them precisely in the environment and food resources. As novel nanomaterials, metal–organic frameworks (MOFs) have attracted significant attention in the fields of adsorption and luminescence sensing due to their rich topology, tunable pore size and shape, high surface area, and abundant active sites. Luminescent metal–organic frameworks (LMOFs) have sprung up as great potential chemical sensors to detect pesticides with fast response, high sensitivity, high selectivity and easy operation. Therefore, in this highlight, we focus on recent progress of MOFs in sensing and adsorbing pesticides, as well as in the possible mechanism of sensing, so as to attract more attention to pesticide detection and adsorption. [ABSTRACT FROM AUTHOR]

A 2D zinc(II)-based metal–organic framework (Zn-MOF) formulated as [Zn(bimpy)(1,4-ndc)]·H2O (1, bimpy = 3,5-bis(1-imidazolyl)pyridine and 1,4-ndc = 1,4-naphthalenedicarboxylic acid) was synthesized by solvothermal reaction. Complex 1 exhibits high water and pH-independent stability. It can detect Fe3+ and ascorbic acid (AA) as a "turn-off" fluorescence probe and a "turn-on" fluorescence probe in aqueous solution with high sensitivity and selectivity, respectively. The detection limits of 1 for Fe3+ and AA are about 8.82 × 10−7 M and 6.12 × 10−7 M, respectively. The fluorescence intensity of the Fe3+@1 system can be obviously recovered after adding AA due to the reduction of Fe3+, which exhibits a fluorescence "turn-on" signal (turn-off–on) for Fe3+@1 toward AA with a low detection limit (3.53 × 10−7 M). Complex 1 still exhibits good detection of Fe3+ and AA after washing and using for five cycles. Additionally, two different multi-input molecular logic gates are established. One is used to distinguish the effect of Fe3+ and Fe2+ on the fluorescence of complex 1, and the other is to further explain the regulation of Fe3+ and AA on the fluorescence of complex 1. This work shows that complex 1 is the first MOF-based "turn-on" fluorescent probe for both Fe3+ and AA in aqueous solution. [ABSTRACT FROM AUTHOR]

Based on the results of the National Survey of Peat Resources (1983-1985) and the investigation results on the peatlands of China, the storage and density of the organic carbon in the peatlands of China were estimated. The total organic carbon storage (OCS) of the peatlands in China, including bare peatlands and buried peatlands, are 1.503 × 10 t, unevenly distributed over 30 provincial level administrative units and 16 climatic zones. Peatland organic carbon storage (POCS) in Sichuan (6.45 × 10 t) and Yunnan provinces (2.91 × 10 t) is the highest, accounting for 62.29% of the total POCS. Humid zone of plateau has the highest POCS of 7.14 × 10 t, especially in the Zoigê Plateau, where the POCS is 6.30 × 10 t, accounting for 41.92% of the total POCS of China. The organic carbon density (OCD) of the peatlands in China mostly ranges from 80 kg/m to 140 kg/m, and the range of the maximum is 270-360 kg/m, and the minimum is less than 80 kg/m. Divided by the Yanshan Mountain, Taihang Mountains and Hengduan Mountains, the peatland oganic carbon density (POCD) is lower on the northwestern side than that on the southeastern side. Jiangxi Province has the highest POCD due to the ancient buried peatlands. The OCD of the bare peatlands is mostly in the range of 60-150 kg/m, and that of the buried peatlands is more than 100 kg/m. In the bare peatlands, the OCD generally increases from the surface layer to the below surface layer, and then decreases with the depth. Although the peatlands area in China is small, the OCS per unit area is far higher than the other soil types, so peatlands protection can effectively mitigate climate change. [ABSTRACT FROM AUTHOR]

The regularity of CH4 emission from marshland in the Sanjiang Plain was studied by sampling in the open field and analyzing under laboratory condition, the annual emission amount is also estimated. By Grey Relatively Analysis we know that the soil temperature in the 10-cm depth of grass-root layer is close related with CH4 emission. CH4 emission has different kinds of diurnal emission modes:before-dawn maximum mode, night maximum mode and irregular fluctuation mode. The seasonal variation trend of CH4 emission rates is going up steadily from May to August and dropping down from September, the maximum lies behind the maximum of temperature. CH4 emission rates of different marshland types are different, the CH4 emission rate of Glyceriaspiculosa — Carex marshland is always higher than that of Carex lasiocarpa marshland. The paper also studies the difference of CH4 emission rates in different managing modes and analyzes the emission rates between China and U. S. A. The result shows: the average value of CH4 emission rate is 17.26mg/(m2·h), the annual amount of CH4 emission is about 0.75Tg. [ABSTRACT FROM AUTHOR]

The Sanjiang Plain of China is a low plain. Its total area is 10.89×104 km2 and marsh area takes up 10.20%. Marsh is a kind of vegetation type with strong carbon-fixing ability among the terrestrial ecosystem and carbon cycle performing in the form of carbon dioxide. This paper discusses the fixation of atmospheric CO2 by marsh plant; the transfer of carbon from marsh to atmosphere; the change of CO2 and vertical transfer of CO2 near atmosphere of the earth; the carbon flow among marsh plants, soil and atmosphere. Some scientific data about the biological production, carbon content of marsh plants and the capacity for releasing and fixing are used to explain the carbon cycle of marsh in the Sanjiang Plain. [ABSTRACT FROM AUTHOR]

There is limited information available on CO2 concentration and flux over marsh. The objective of this work was to characterize CO2 concentration and flux within and above marsh plant ( Carex lasiocarpa Ehrh. and C. pseudocuraica F. Schm) canopy at heights 0.5, 1.0 and 1.5 m. CO2 concentration was measured sequentially every 3 hours by using an infrared gas analyzer. Soil and air temperature, wind speed, net radiation and soil heat flux were also measured simultaneously. Extremely daily minimum and maximum CO2 concentration ranged from 250 to 754 µmd/mol for the 4-year work. The typical minimum and maximum values ranged from 314 to 464 µmol/mol at the height of marsh plant (about 0.5 m) during the fruiting period and mature date. The seasonal changes in CO2 concentration show that the minimum CO2 concentration occurred in the fruiting period and mature date, and both of their minimum values were 314 µmol/mol. This illustrates that CO2 consumed by photosynthesis was stable during the period. The flux of CO2 can be thought as a turbulent diffusion phenomenon. By micrometeorological methods, the diurnal CO2 fluxes were measured in the flowering period, fruiting period, early mature date, late mature date and yellow-ripe stage. Their values were −0.18, 38.15,24.13,10.9 and 4.91 µmol/mol respectively. [ABSTRACT FROM AUTHOR]

Mire is the product of the Quaternary. It mostly formed, developed and declined after the postglacial age. Therefore the chemical element analysis, spore-pollen analysis,C dating, mire plant determination for mire sediment, and the study on hierarchy relation of mire sediment, can provide a lot of information for restoring paleogeography, paleoclimate and environmental change. So some people called mire sediment-peat as 'database of environment'. [ABSTRACT FROM AUTHOR]

The detection of water pipeline leakage is important to ensure that water supply networks can operate safely and conserve water resources. To address the lack of intelligent and the low efficiency of conventional leakage detection methods, this paper designs a leakage detection method based on machine learning and wireless sensor networks (WSNs). The system employs wireless sensors installed on pipelines to collect data and utilizes the 4G network to perform remote data transmission. A leakage triggered networking method is proposed to reduce the wireless sensor network's energy consumption and prolong the system life cycle effectively. To enhance the precision and intelligence of leakage detection, we propose a leakage identification method that employs the intrinsic mode function, approximate entropy, and principal component analysis to construct a signal feature set and that uses a support vector machine (SVM) as a classifier to perform leakage detection. Simulation analysis and experimental results indicate that the proposed leakage identification method can effectively identify the water pipeline leakage and has lower energy consumption than the networking methods used in conventional wireless sensor networks. [ABSTRACT FROM AUTHOR]