Potential role of tanycyte-derived neurogenesis in Alzheimer's disease

Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier function.However, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could provide valuable insights into potential therapeutic strategies for Alzheimer's disease and related conditions.

Highly efficient CO_(2) capture using 2-methylimidazole aqueous solution on laboratory and pilot-scale

To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of alkanolamines.Here,to pursue a substitute for the amine-based approach to improve the CO_(2) capture efficiency and decrease the energy cost further,we report a new carbon capture approach using a 2-methylimidazole(mIm)aqueous solution.The properties and sorption behaviors of this approach have been experimentally investigated.The results show that the mIm solution has higher CO_(2) absorption capacity under relatively higher equilibrium pressure(>130 kPa)and lower desorption heat than the methyldiethanolamine solution.91.6%sorption capacity of mIm solution can be recovered at 353.15 K and 80 kPa.The selectivity for CO_(2)/N_(2) and CO_(2)/CH_(4) can reach an exceptional 7609 and 4324,respectively.Furthermore,the pilot-scale tests were also performed,and the results demonstrate that more than 98%of CO_(2) in the feed gas could be removed and cyclic absorption capacity can reach 1 mol·L^(-1).This work indicates that mIm is an excellent alternative to alkanolamines for carbon capture in the industry.

From the perspective of experimental practice: High-throughput computational screening in photocatalysis

Photocatalysis,a critical strategy for harvesting sunlight to address energy demand and environmental concerns,is underpinned by the discovery of high-performance photocatalysts,thereby how to design photocatalysts is now generating widespread interest in boosting the conversion effi-ciency of solar energy.In the past decade,computational technologies and theoretical simulations have led to a major leap in the development of high-throughput computational screening strategies for novel high-efficiency photocatalysts.In this viewpoint,we started with introducing the challenges of photocatalysis from the view of experimental practice,especially the inefficiency of the traditional“trial and error”method.Sub-sequently,a cross-sectional comparison between experimental and high-throughput computational screening for photocatalysis is presented and discussed in detail.On the basis of the current experimental progress in photocatalysis,we also exemplified the various challenges associated with high-throughput computational screening strategies.Finally,we offered a preferred high-throughput computational screening procedure for pho-tocatalysts from an experimental practice perspective(model construction and screening,standardized experiments,assessment and revision),with the aim of a better correlation of high-throughput simulations and experimental practices,motivating to search for better descriptors.

Extreme Cold Events from East Asia to North America in Winter 2020/21:Comparisons,Causes,and Future Implications

Three striking and impactful extreme cold weather events successively occurred across East Asia and North America during the mid-winter of 2020/21.These events open a new window to detect possible underlying physical processes.The analysis here indicates that the occurrences of the three events resulted from integrated effects of a concurrence of anomalous thermal conditions in three oceans and interactive Arctic-lower latitude atmospheric circulation processes,which were linked and influenced by one major sudden stratospheric warming(SSW).The North Atlantic warm blob initiated an increased poleward transient eddy heat flux,reducing the Barents-Kara seas sea ice over a warmed ocean and disrupting the stratospheric polar vortex(SPV)to induce the major SSW.The Rossby wave trains excited by the North Atlantic warm blob and the tropical Pacific La Nina interacted with the Arctic tropospheric circulation anomalies or the tropospheric polar vortex to provide dynamic settings,steering cold polar air outbreaks.The long memory of the retreated sea ice with the underlying warm ocean and the amplified tropospheric blocking highs from the midlatitudes to the Arctic intermittently fueled the increased transient eddy heat flux to sustain the SSW over a long time period.The displaced or split SPV centers associated with the SSW played crucial roles in substantially intensifying the tropospheric circulation anomalies and moving the jet stream to the far south to cause cold air outbreaks to a rarely observed extreme state.The results have significant implications for increasing prediction skill and improving policy decision making to enhance resilience in“One Health,One Future”.

再生混凝土耐久性研究综述

通过对近年来再生混凝土相关文献的整理,了解再生混凝土研究现状及趋势,深入分析了再生混凝土的耐久性能,提出未来再生混凝土的研究方向。

Study on force chain evolution of rice straw with different length during vibrational compression

This paper explores the mechanism of force chain evolution and voidage change under vibrational and non-vibrational compression conditions of rice straw of different lengths.Simulations were used to explore the force chain evolution and voidage variation mechanism under different conditions.The re-sults show that under non-vibrational compression,the strong force chain passes from top to bottom in vertical direction and from center to periphery in tangential direction.Under vibrational compression,the force chain passes from top and bottom to center in vertical direction and the force chain evolves from outer ring to interior and exterior in tangential direction.The number of strong chains,voidage and standard deviation of the mean pressure under vibratory compression are lower than the values under non-vibratory compression.Vibration promotes stress transfer and enhancement,velocity enhancement and density enhancement.This study analyzes the mechanical properties of different lengths straw during vibrational and non-vibrational compression from a detailed viewpoint.

Masses of the conjectured H-dibaryon at different temperatures

We present a lattice QCD determination of masses of the conjectured H-dibaryon,denoted as mH,at nine different temperatures:T/T_(c)=0.24,0.63,0.76,0.84,0.95,1.09,1.27,1.52,and 1.90.The masses of baryons N,Σ,Ξ,andΛat different temperatures were also computed.The simulations were performed on an anisotropic lattice with N_(f)=2+1 flavours of clover fermion at a quark mass corresponding to mπ=384(4)MeV.The thermal ensembles were provided by the FASTSUM collaboration,whereas the zero temperature ensembles were provided by the Hadspec collaboration.We also calculated the spectral density of the correlation function of those particles.The spectral density distributions show a rich peak structure at the lowest temperature;at intermediate temperatures,the mass values of those particles obtained by the extrapolation method reflect a two-peak structure.While the spectral density for the octet baryon becomes smooth at T/T_(c)=1.27,1.52,and 1.90,the spectral density for the H-dibaryon becomes smooth at T/T_(c)=1.90.At T/T_(c)=0.24,the mass difference of the H-dibaryon andΛpair,expressed asΔm=m_(H)−2m_(Λ),was estimated to beΔm=−14.6(6.2)MeV,which suggests the existence of a bound H-dibaryon state.

Low-concentration and multi-component NMHCs capture from oil field exhaust using porous ZIF-8/iso-hexadecane slurry

Non-methane hydrocarbons(NMHCs)are a common type of volatile organic compounds(VOCs)pollutant in the petrochemical industry and have attracted widespread attention because of their adverse health effects and environmental impacts.In this paper,we report a new porous slurry formed with zeolitic imidazolate framework-8(ZIF-8)and iso-hexadecane to capture the low-concentration and multi-component NMHCs(mainly ethane(C_(2)H_(6)),propane(C_(3)H_(8)),and n-butane(n-C_(4)H_(10)))from the oil field exhaust.The sorption capacity of C_(2)H_(6)in the slurry is significantly higher than that of nitrogen(N_(2))and methane(CH_(4)).Moreover,the slurry demonstrated a clear advantage for C_(2)H_(6)over N_(2)and CH_(4)in competitive adsorption through the pressure-drop curves.In the NMHCs capture experiments,the C_(3)H_(8)and n-C_(4)H_(10)concentrations after purification can be reduced to below 100 ppm,while the C_(2)H_(6)concentration can reach approximately 180 ppm.More encouragingly,in the breakthrough tests,the slurry exhibits a perfect kinetic separation selectivity for multi-component NMHCs.Furthermore,to avoid structural collapse of ZIF-8 material during long-term use in acidic and wet environments,a certain amount of 2-methylimidazole was retained in the slurry as a protective agent in the material synthesis process.In this way,the ZIF-8 materials in the slurry can retain the stable characteristic structure in an aqueous and acidic environment and keep the capture capacity for NMHCs without degradation.We believe the porous ZIF-8/iso-hexadecane slurry is a promising capture agent for low-concentration and multi-component NMHCs with strong purification capacity and stability.

Vibration analysis and topology optimization of the header of full-feeding rice combine harvester

The header frame of full-feeding rice combine harvester was characterized by severe vibration due to the excitation force generated by the movement of each working part.In order to solve the problem,the parametric model of the header frame was established,and the accuracy of the finite element model was verified by comparison of the results of the free modal analysis and free vibration modal test based on Eigensystem Realization Algorithm(ERA).Then the constrained modal frequencies were calculated and compared with the external excitation source frequencies,the results showed that the first and eighth order modal natural frequencies were coupled with the excitation frequencies of the threshing cylinder and the engine respectively,which were apt to resonate.To avoid resonance and achieve lightweight design,topology optimization,and finite element analysis were carried out.The optimization results showed that the strength and rigidity meet the requirements and the weight was 14.17%lower than before.The first and eighth order modal natural frequencies were far away from the excitation frequencies range of the threshing cylinder and engine,and the frequencies were far away from the range of each excitation frequency,which effectively avoided the occurrence of resonance.Field experiments showed that the peak value of the vibration acceleration in the three directions of the 8 measuring points of the optimized header frame was significantly reduced,which effectively reduced the vibration of the header frame during harvest.This study provides a method for obtaining the vibration characteristics of key components of agricultural machinery and provides a reference for the weight and vibration reduction of header frames of rice,wheat,rape,and other crop combine harvesters.

Structure optimization of cam executive component and analysis of precisely applying deep-fertilization liquid fertilizer

Since there are some problems in the previous cam of deep-fertilization liquid fertilizer applicator,such as poor precision and low-fertilization performance,a method of the contour line of a cam was proposed based on Matlab GUI development platform.Bernoulli’equation between the liquid fertilizer and the pressure valve of the fertilizer-spraying needle was founded.Moreover,the motion angles of a rise travel and return travel were corrected and the corresponding parameters of the contour line of the cam were obtained.Equations of cam moving from rise travel to return travel were derived according to the simple harmonic motion.In addition,3D model of cam was established by applying the Pro/E software and the rationality of the cam design was verified.The static analysis of the cam was carried out under working conditions and the corresponding dynamics analysis was performed based on D’Alembert’s principle.And then relationships between the binding force and the drag torque were obtained.A bench test indicates that when the pressure of a hydraulic pump is 0.5 MPa and the velocity of a output shaft is 50 r/min,the average consumption of the fertilizer is 19.7 mL for each measurement,which meets the corresponding agronomic requirement,i.e.20 mL.When the rotation angle of the cam is 8.6°and the rise displacement of a plunger is 0.84 mm,the mouth of the fertilizer-spraying needle sprayed liquid fertilizer as soon as it got into the soil and stopped spraying as soon as it got out of the soil.The results show that the designed contour line of the cam meets the requirement,that is,the mouth of the fertilizer-spraying needle should spray liquid fertilizer as soon as it gets into the soil and stop spraying as soon as it gets out of the soil,which meets the agronomic requirements,that is,fertilizer should be sprayed deeply and precisely.And this study lays a theoretical foundation for designing the cam of intermittent type distributor and provides relevant parameters.

Root tensile strength of terrace hedgerow plants in the karst trough valleys of SW China:Relation with root morphology and fiber content

Root tensile strength is commonly affected by root morphology and fiber content,which combinedly affect the effectiveness of terrace hedgerow on controlling soil erosion in sloping farmland.However,the relationships between these root characteristics are still elusive.This study aimed to compare the root tensile strength,root morphologies,and root fiber contents,and quantify their differences among different plant species.Complete root systems of three terrace hedgerow plant species,i.e.,O.bodinieri,V.villosa,and D.lablab L.were sampled for detecting root morphologies and fiber contents at different slope positions on a representative hillslope in karst trough valley.Single root specimens were collected to measure root tensile properties for these three plant species.Results showed that most root morphological parameters were the highest in O.bodinieri,followed by D.lablab L.Three plant species presented the same dominant diameter class as<1.0 mm,and root volumes as<1.50 cm3.Cellulose with contents closing to 50%was the main fiber type,and increased significantly linearly with the increasing root diameter in both O.bodinieri and V.villosa.The highest tensile strength and Young's modulus were found in D.lablab L.,while the best ultimate tensile force and ultimate elongation were displayed in O.bodinieri.Root diameter showed negative power relationships with tensile strength and Young's modulus,a positive power relationship with ultimate tensile force,and a positive linear relationship with ultimate elongation.Our results will deepen the understanding of the terrace hedgerow functions for controlling soil erosion worldwide.

柔性三维网络钒酸铁纳米片阵列/碳布作为镁离子电池高性能正极材料

镁离子电池由于具有高安全性、低成本等优点,近年来受到了广泛的关注.然而,镁离子缓慢的扩散动力学使其难以找到合适的具有良好电化学性能的正极材料.在此,我们设计并合成了一种新颖的柔性三维网络钒酸铁纳米片阵列/碳布(3D FeVO/CC)作为镁离子电池的无粘结剂正极材料.与原始钒酸铁纳米片(FeVO)相比,结构改善的3D无粘结剂电极能够实现全面的电化学性能优化,包括高比容量(270 mA h g^(-1))和更长的循环寿命(超过5000次循环).这种可实现的高能量密度来源于电子和离子动力学的协同优化,而循环稳定性得益于稳固的分级结构.本文采用原位X射线衍射和拉曼技术对镁离子储存过程中FeVO单相反应机理进行了研究.此外,还组装了柔性镁离子全电池(3D FeVO/CC|MgNaTi(3)O_(7)),并展示出一定的应用潜力.本工作证明了3D FeVO/CC是一种有潜力的正极材料,可以满足高性能镁离子电池的要求,也为提高镁离子电池正极材料的电化学性能开辟了一条新的途径.

Design and experiment of spray and rotary tillage combined disinfection machine for soil

A spray and rotary tillage combined disinfection machine for soil was designed to solve the serious problems of plant diseases and insect pests,and it was divided into two operations which were soil disinfection and rotary tillage.The main structure and working principle of this machine were illustrated and analyzed.The reasonable structural parameters of the key parts of this machine were optimized,such as spraying disinfection system and rotary tillage land preparation system.To optimize the working performance and obtain better operation parameters,the orthogonal experiments were carried out to analyze the influences of three factors(forward speed of driving machine,rotational speed of rotary tillage,and working pressure)on the working performance.The mixing uniformity coefficient and the variation coefficient of spraying were selected for evaluating working performance.The range analysis and variance analysis were studied based on experimental data.The results showed that,the mixing uniformity coefficient of spraying was 93.95%and the variation coefficient was 6.01%with a working speed of 3 km/h,rotational speed of 2000 r/min and working pressure of 2.0 MPa.The machine can meet the agronomic requirements of disinfection and plowing,which was designed simply,compactly and strong applicability.The results can provide a guidance and technical support for preventing the plant diseases and insect pests,developing sustainable and ecological agriculture and improving the efficiency of compound cultivation.

Experimental study on the correlation between hill direct seeding rate and field seedling rate of typical rice varieties in cold areas

In order to examine the relationship between the seeding rate of a hill-direct-seeding machine and seedling rate in field,six rice varieties typical for cold areas were selected to conduct the indoor germination tests and field seedling experiment using a hill-direct-seeding machine.Indoor germination and field seedling tests were performed to study the correlation among the mechanical precision seeding process,machine seeding rate and field seedling rate.The results showed that the indoor germination rates were higher than 90%.The series of spoons was adaptable to the hill-direct-seeding process.The number of seeds was 28-30,18-20 and 8-10 grains/hill.The field seedling rates were higher than 85%.The rice variety of Suijing-18 achieved the best field seedling rate,and the highest seeding rate was 18-20 grains/hill,while the average field seedling rate was 94.25%.On this basis,the action law of the hill-direct-seeding machine and the main factors influencing the field seedling rate were analyzed.Mechanical vibration resulted in a higher average seeding rate of the middle seed metering device of the hill-direct-seeding machine than that of both ends.The force between the seed spoons and rice seeds mechanically damaged the seed buds,resulting in the actual field seedling rate being lower than the ideal indoor germination rate.The experimental results can provide a reference for the selection of typical direct seeding rice varieties,the improvement of key components of hill-direct-seeding machines,and the promotion of agronomic models.

Screening and impurity removal device to improve the accuracy of moisture content detection device for rice

An online detection device that used the capacitance method to detect the moisture content of rice in a combine harvester was designed and found a low detection accuracy because of the high impurity content of the samples.To solve this problem,a screening and impurity removal device was designed in this study,and the structural parameter range of the screw conveyor was the focus of the design.To determine the best structural parameters and operating parameters of the device,models of rice grains and short stems were established by the discrete element method.The Discrete Element Method(DEM)simulation test was carried out according to the Box-Behnken response surface method.When the rotating speed was 300 r/min,the diameter of spiral blade was 146 mm,the pitch was 80 mm,the diameter of rotating shaft was 30.6 mm,and the minimum impurity content was 0.27%.The density distributions and movement characteristics of the rice grains and short stems in the optimized screening and impurity removal device were studied.An experiment was carried out to compare data for the moisture content of rice measured by the online moisture content detection device before and after the installation of the screening and impurity removal device and the results of the 105°C drying method.The results showed that the impurity content of rice ranged from 0.26%to 0.37%,and the maximum effective screening rate was 90.99%after screening.The screening and impurity removal device significantly reduced the error in the moisture content measured by the online detection device,the error range was 0.12%-2.55%.This study provides a method for accurate online detection of moisture content and provides a reference for the design and simulation of related screening devices.

Improving discharge voltage and ion storage dynamic in polyaniline via modulation of carrier charge density for magnesiummetal batteries

Rechargeable magnesium-metal batteries(RMBs)have gained much attention due to their abundant resources as well as high safety.However,the high charge density of Mg^(2+)is one of the main reasons for the slow kinetics performance of RMBs,and modulation of the charge density is an important strategy to improve the kinetics and electrochemical performance of RMBs.Herein,we report on the conductive polymer polyaniline(PANI)for RMBs,which is found to have excellent kinetics and high discharge voltage when storing MgCl^(+).In the storage of MgCl^(+),PANI exhibits a high average discharge voltage platform is 2.3 V vs.Mg^(2+)/Mg,which is higher than that in storage of Mg^(2+).We demonstrated the reversible intercalation/de-intercalation of MgCl^(+)in PANI accompanying with the reversible transformation between the quinone ring(C–C,–N=)and the benzene ring(C=C,–NH–)during charging and discharging.Density functional theory calculation reveals that PANI exhibit higher voltages(2.25 V vs.1.82 V)along with lower diffusion energy barriers(1.27 eV vs.1.55 eV)for MgCl^(+)storage compared to Mg^(2+)storage.This work refines the storage mechanism of PANI in RMBs and provides new guidelines for the application of PANI in RMBs.