Altitudinal variations of hydraulic traits in Faxon fir(Abies fargesii var.faxoniana):Mechanistic controls and environmental adaptability

Global climate change has been seen to result in marked impacts on forest ecosystems such as accelerated tree mortality worldwide due to incidental hydraulic failure caused by intensified and more frequent occurrence of extreme drought and heat-waves.However,it is well understood how the tree hydrological strategies would adjust to environmental variability brough about by climate changes.Here we investigated the hydraulic adjustment as a mechanism of acclimation to different climate conditions along an altitudinal gradient in Faxon fir(Abies fargesii var.faxoniana)–a tree species that plays a key role in conservation of wildlife and maintenance of ecosystem services in subalpine forests.The hydraulic traits and selective morphological and physiological variables were measured seasonally along an altitudinal gradient from 2,800 to 3,600 m a.s.l.We found that the native percentage loss of conductivity(PLC)increased with altitude across the seasonal measurements.Both the native sapwood-specific hydraulic conductivity(Ks)and native leaf-specific hydraulic conductivity(Kl)significantly decreased with altitude for measurements in July and October,coinciding with the timing for peak growth and pre-dormancy,respectively.The morphological traits varied toward more conservative tree hydrological strategies with increases in altitude,exhibiting trade-offs with hydraulic traits.The total non-structural carbohydrates in both needle(NSCNeedle)and branch(NSCBranch)as well as photosynthetic capacity of current-year leaves played variable roles in maintaining the integrity of the hydraulic functioning and shaping the hydraulic adjustment under prevailing environmental conditions.Our findings indicate that Faxon fir possesses some degree of hydraulic adaptability to water limitation imposed by climate fluctuations in subalpine region through morphological and physiological modifications.

A Study of the Artificial Vegetation Restoration Technology in the Wenchuan Earthquake Area

The situation of plants on the slope can reflect the effect of vegetation restoration during the process of artificial vegetation recovery.Taking the typical damaged slope of Wenchuan earthquake area as the research object,through observing the vegetation situation of deserted slope,the results show that compositae plants and gramineous plants are suitable for being pioneer plants and dominant in community; during the vegetation succession,many compositae and gramineous species invade,but there is no magaphanerophytes invading; as time goes by,the herbaceous species and diversity increase gradually,so the ecosystem becomes more stable and the gradient is important for the vegetation restoration.

Biomass and Nutrient Accumulation Characteristics of Young Stands of Alnus cremastogyne

To investigate plant biomass and nutrient distribution and accumulation in organs of Alnus cremastogyne at different ages from 1 to 4 years, the biomass, N, P, K, Ca, Mg, Fe and Zn were tested. The results showed that the average biomass of the whole tree and the biomass of leaf, branch, stem, and root were in positive correlation with tree age, but the growth rate of biomass had a decreasing trend with the tree age increasing, and only the biomass proportion of the trunk in the whole individual plant showed an increasing trend with age. The contents of nutrient elements in organs showed an order of N 〉 Ca 〉 K 〉 Mg 〉 P 〉 Fe 〉 Zn ; and the contents of N, P and K were higher in the leaf than in other organs, and the contents of Ca, Mg and Fe in the root were higher than in other organs. The accumulations of N, P, K, Ca, Mg and Zn were the highest in the trunk, and that of Fe was the highest in the root. The annual net accumulations of N, P, K, Ca and Mg in the average trees from 1 to 4 years old were 17.07, 40.79, 95.82 and 106.71 g, respectively, and the annual net accumulations of microelements （Fe and Zn） were 335.04, 577.26, 1267 and 1525.27 mg, respectively.

Combinatorial synthesis of redox-responsive cationic polypeptoids for intracellular protein delivery application

Biologics play an essential role in treating various indications from cancers to the metabolic diseases,while the current development of new classes of intracellular-acting protein drugs is still hindered because of high molecular mass and overall hydrophilicity of proteins creating extremely poor permeability across cell membrane.Hence,there remains an unmet need to develop safe,potent approaches to augment intracellular protein delivery efficiency.Here,we described a facile multicomponent reaction system for generating a small library of redox-responsive cationic polypeptoids with high biocompatibility.The co-assembly of optimized polymer with protein leads to the formation of compacted nanocomplexes with smaller size and high encapsulation efficiency,thus improving cellular internalization via the macropinocytosis and/or caveolae-mediated endocytosis mainly.After endo-lysosomal escape,the nanocomplexes can be disassociated to efficiently release cargo proteins into the cytosol,owing to the intracellular glutathione(GSH)-triggered rapid cleavage of disulfide bonds in polymers backbone.As a result,we screened a promising platform reagent for efficient cytosolic protein delivery application.

The protein corona modulates the inflammation inhibition by cationic nanoparticles via cell-free DNA scavenging

A central paradigm in nanomedicine is that when synthetic nanoparticles(NPs)enter the body,they are immediately cloaked by a corona of macromolecules(mostly proteins)that mediates the role of the physico-chemical properties in the NP biological functions(the“coronation paradigm”).In this work,we focused on the assessment of the“coronation paradigm”for cationic NPs(cNPs)used as rheumatoid arthritis(RA)drugs due to their ability to scavenge cell-free DNA(cfDNA).We fabricated series of cNPs uniformly coated with single or di-hydroxyl groups and different types of amino groups and showed that hydroxylated nanoparticles displayed a prolonged retention in inflamed joints and greater anti-inflammatory effect in collagen-induced arthritis(CIA)rats than the non-hydroxylated analogues.Especially,the cNPs with secondary amines and a di-hydroxyl shell showed the best performance among the tested cNPs.Proteomic analysis showed that the cNPs with a di-hydroxyl shell adsorbed less opsonin proteins than the cNPs carrying mono hydroxyl groups and non-hydroxylated ones,which may provide a mechanistic explanation for the different biodistribution profiles of cNPs.Thus,this study suggests that the protein corona mediates the effects of the surface chemistry on the fate and functions of cNPs as anti-RA drugs.

Lane-change path planning and control method for self-driving articulated trucks

Purpose–This study aims to develop an automatic lane-change mechanism on highways for self-driving articulated trucks to improve traffic safety.Design/methodology/approach–The authors proposed a novel safety lane-change path planning and tracking control method for articulated vehicles.A double-Gaussian distribution was introduced to deduce the lane-change trajectories of tractor and trailer coupling characteristics of intelligent vehicles and roads.With different steering and braking maneuvers,minimum safe distances were modeled and calculated.Considering safety and ergonomics,the authors invested multilevel self-driving modes that serve as the basis of decision-making for vehicle lane-change.Furthermore,a combined controller was designed by feedback linearization and single-point preview optimization to ensure the path tracking and robust stability.Specialized hardware in the loop simulation platform was built to verify the effectiveness of the designed method.Findings–The numerical simulation results demonstrated the path-planning model feasibility and controller-combined decision mechanism effectiveness to self-driving trucks.The proposed trajectory model could provide safety lane-change path planning,and the designed controller could ensure good tracking and robust stability for the closed-loop nonlinear system.Originality/value–This is a fundamental research of intelligent local path planning and automatic control for articulated vehicles.There are two main contributions:thefirst is a more quantifiable trajectory model for self-driving articulated vehicles,which provides the opportunity to adapt vehicle and scene changes.The second involves designing a feedback linearization controller,combined with a multi-objective decision-making mode,to improve the comprehensive performance of intelligent vehicles.This study provides a valuable reference to develop advanced driving assistant system and intelligent control systems for self-driving articulated vehicles.