Mitochondria-engine with self-regulation to restore degenerated intervertebral disc cells via bioenergetic robust hydrogel design

Previous studies have confirmed that intervertebral disc degeneration(IDD)is closely associated with inflammation-induced reactive oxygen species(ROS)and resultant cell mitochondrial membrane potential(MMP)decline.Clearance of ROS in an inflammatory environment is essential for breaking the vicious cycle of MMP decline.Additionally,re-energizing the mitochondria damaged in the inflammatory milieu to restore their function,is equally important.Herein,we proposed an interesting concept of mitochondrion-engine equipped with coolant,which enables first to“cool-down”the inflammatory environment,next to restore the MMP,finally to allow cells to regain normal energy metabolism through materials design.As such,we developed a multifunctional composite composed of a reactive oxygen species(ROS)-responsive sodium alginate/gelatin hydrogel infused into a rigid 3D-printed thermoplastic polyurethane(TPU)scaffold.The TPU scaffold was coated with conductive polypyrrole(PPy)to electrophoretically deposit L-arginine,which could upregulate the Mammalian target of rapamycin(mTOR)pathway,thus increasing MMP and energy metabolism to stimulate extracellular matrix synthesis for IVD repair.While the ROS-responsive hydrogel acting as the“mito-engine coolant”could scavenge the excessive ROS to create a favorable environment for IVD cells recovery.Demonstrated by in vitro and in vivo evaluations,the mito-engine system markedly promoted the proliferation and collagen synthesis of nucleus pulposus cells while enhancing the mitochondrial respiration and MMP under oxidative stress.Radiological and histological assessments in vivo revealed the efficacy of this system in IVD repair.This unique bioinspired design integrated biomaterial science with mitochondrial biology,presents a promising paradigm for IDD treatment.

Corrigendum to“Mitochondria-engine with self-regulation to restore degenerated intervertebral disc cells via bioenergetic robust hydrogel design”[Bioact.Mater.40C(2024)1–18]

The authors regret that in Fig.2Aa of the article,the images for TPUPPy and TPU-aa in the first column were mistakenly duplicated due to a formatting error.The correct version of Fig.2 is provided below,along with the original data for reference.The authors confirm that the rest of the article remains unaffected.

Analysis of promoter activity reveals that GmFTL2 expression differs from that of the known Flowering Locus T genes in soybean

Regulation of flowering is one of the key issues in crop yield. The Floiuering Loews T(FT) gene is a well-known florigen, which integrates various signals from multiple flowering-regulation pathways to initiate flowering. We previously reported that there are at least six FT genes(GmFTLl-6) in soybean displaying flowering activity. However, the individual functions of genes GmFTLl-6 remain to be identified. In this study, we cloned the GmFTL2 promoter(GmFTLpro) from soybean(Glycine max) cultivar Tianlong 1 and analyzed its motifs bioinformatically and its expression patterns using both a transgenic approach and quantitative RT-PCR(qRT-PCR). In GmFTLpro::GUS transgenic lines, GUS signals were enriched in cotyledons, hypocotyledons, pollen, embryos, and root tips in a photoperiod-independent manner. qRT-PCR confirmed the GUS reporter results. Our results suggest that GmFTL2 expression is regulated by developmental and tissue-specific clues and plays roles in seedling establishment and the development of micro game tophytes, embryos, and roots.

Comparison of social interaction and neural activation in the main olfactory bulb and the accessory olfactory bulb between Microtus mandarinus and Microtus fortis

To gain insight into the function of AOB and MOB during different social interaction and in different vole species,the behaviors and neural activation of the olfactory bulbs in social interactions of mandarin voles Microtus mandarinus and reed voles Microtus fortis were compared in the present research.Mandarin voles spent significantly more time attacking and sniffing their opponents and sniffing sawdust than reed voles.During same sex encounters,mandarin voles attacked their opponents for a significantly longer time and sniffed its opponent for shorter time compared with male-female interactions.However,no significant behavioral differences were found during encounters of two individual reed voles,regardless of gender composition of the pair.Using c-Fos as an indicator of neural activation,we observed that neural activation was significantly higher in almost all sub-regions of the main olfactory bulb(MOB)and the accessory olfactory bulb(AOB)of mandarin voles compared with reed voles.Numbers of c-Fos-ir neurons in almost all sub-regions of the AOB and the MOB during male-female interactions were also higher than those in interactions of the same sex.Anterior-posterior ratios of Fos-ir neurons in the AOBM(AOBMR)and the AOBG(AOBGR)in male-female interaction were significantly higher than those in interaction of the same sex.The AOBMR of male mandarin voles and reed voles were larger than those of females in male-female interactions.Behavioral patterns are consistent with cellular activity patterns.Consistent level of neural activation in MOB and AOB suggests important roles of both the main olfactory bulb and the accessory olfactory bulb in social interaction in two species.

Moirésuperlattice modulations in single-unit-cell FeTe films grown on NbSe_(2)single crystals

Interface can be a fertile ground for exotic quantum states,including topological superconductivity,Majorana mode,fractal quantum Hall effect,unconventional superconductivity,Mott insulator,etc.Here we grow single-unit-cell(1UC)FeTe film on NbSe_(2)single crystal by molecular beam epitaxy(MBE)and investigate the film in-situ with a home-made cryogenic scanning tunneling microscopy(STM)and non-contact atomic force microscopy(AFM)combined system.We find different stripe-like superlattice modulations on grown FeTe film with different misorientation angles with respect to NbSe_(2)substrate.We show that these stripe-like superlattice modulations can be understood as moirépattern forming between FeTe film and NbSe_(2)substrate.Our results indicate that the interface between Fe Te and NbSe2 is atomically sharp.By STM-AFM combined measurement,we suggest that the moirésuperlattice modulations have an electronic origin when the misorientation angle is relatively small(≤3°)and have structural relaxation when the misorientation angle is relatively large(≥10°).

The effect of low-temperature event on the survival and growth of Juglans mandshurica seedlings within forest gaps

In forest ecosystems, gap formation changes the allocation of abiotic resources and thus affects the survival and growth of understory plants. However, how tree seedling survival and growth respond to low-temperature events and the influencing mechanisms remain unclear. To clarify how low-temperature event limits the survival and growth of tree seedlings in the montane regions of eastern Liaoning Province, northeast China, we investigated temperature and light intensity within secondary forest gaps, and the survival and growth of Juglans mandshurica seedlings after a low-temperature event in the spring of 2014. Damage to seedlings due to low temperature sig- nificantly varied in different aspects. Seedlings in gaps on southeast-facing slopes were the most seriously damaged, followed by those in gaps on northeast-facing slopes. In contrast, seedlings in west-facing gaps and in control plots without slope aspect were not damaged. The freezing injury index for seedlings was negatively correlated with minimum temperature （r = - 0.608, P 〈 0.01）, but it was positively correlated with light intensity （r= 0.818, P 〈 0.01）. In addition, height and root collar diameter of damaged seedlings were significantly lower than those of the undamaged seedlings （P 〈 0.01） during the early growing season （April-July）, but no significant difference were observed during the late growing season （July-Oc- tober） （P 〉 0.05）. The extent of seedling damage was directly related to slope aspect. Low temperature and high light intensity were found to be the dominant factors affecting extent of damage to seedlings on southeast- and northeast-facing slopes.

Direct observation of the scaling relation between density of states and pairing gap in a dirty superconductor

Theories and experiments on dirty superconductors are complex but important in terms of both theoretical fundamentals and practical applications.These activities are even more challenging when magnetic fields are present because the field distribution,electron density of states,and superconducting pairing potentials become nonuniform.Here,we present tunneling microspectroscopic experiments on NbC single crystals and demonstrate that NbC is a homogeneous dirty superconductor.When applying magnetic fields to the samples,we found that the zero-energy local density of states and the pairing energy gap followed the explicit scaling relation proposed by de Gennes for homogeneous dirty superconductors in high magnetic fields.More significantly,our experimental findings indicate that the validity of the scaling relation extends to magnetic field strengths far below the upper critical field,calling for a new nonperturbative understanding of this fundamental property in dirty superconductors.On the practical side,we used the observed scaling relation to derive a simple and straightforward experimental scheme for estimating the superconducting coherence length of a dirty superconductor in magnetic fields.

Function and mechanism of traditional Chinese medicine in the prevention and treatment of Parkinson＇s disease

Parkinson’s disease （PD） was frst discovered 200 years ago. The current gold standard of clinical treatment is still mainly levodopa replacement therapy. Traditional Chinese medicine is the foundation of traditional medicine in China. Chinese herbs and acu-puncture both exhibit remarkable effcacy in the treatment of PD. Clinical studies on the treatment of PD using Chinese herbs have confrmed that the combined use of Chinese herbs and the levodopa formulation can signifcantly increase the treatment effect and reduce toxic side effects. Basic studies further confrmed that various Chinese herbs and their monomeric substances can protect dopaminergic neurons in PD models. The major mechanisms include anti-infammation, anti-oxidant, anti-apoptosis, neuroprotection, mitochondrial function protection, and regulation of gut microbiota. The function of acupuncture in the treatment of PD has also gradually received extensive attention in China and other countries. Acupuncture not only has peculiar advantages in the improvement of symptoms of PD patients, but also can attenuate adverse drug reactions, delay disease progression, and increase the quality of life of patients. Basic studies further confrmed that acupuncture can improve many motor symptoms in animal models of PD and has cumulative effects and follow-up effects. The major mechanisms include dopamin-ergic neuron protection functions, anti-infammation and anti-oxidant effects, and the regulation of related neuro-transmitters and neural circuits. The clinical application of acupuncture and Chinese herbs still requires strict ran-domized, double-blind, controlled design, multi-centre and large-sample size evidence-based clinical studies and follow-up observations of long-term effcacy to support the effect. In addition, the multi-target and multi-pathway therapeutic mechanisms need further studies.

Detection of Ratoon Stunting Disease in Virus-free Seedcane via Real-time Fluorescence Quantitative PCR

This study was to develop the real-time fluorescence quantitative PCR technique for detecting the ratoon stunting disease （RSD） in virus-free seedcane seedlings. Healthy tissue culture seedlings were obtained from six plants of sugarcane ROC22, which had been confirmed RSD-positive by detecting the sugarcane juice, by employing the sugarcane seedlings production protocol. Real-time fluorescence quantitative PCR was used to detect RSD pathogens in tissue culture sam- pies. The results showed that target fragment of RSD pathogens was not found in all 10 samples in real-time fluorescence quantitative PCR, with the Ct values of 37 - 39. The healthy tissue culture sugarcane seedlings do not carry RSD pathogens, indicating that adopting healthy seedcane seedlings production technique could thoroughly get rid of RSD pathogens.

Effects of Seed Soaking with Paclobutrazol on Tillering and Physio-logical Characteristics of Sugarcane Seedlings

In order to study the effects of seed soaking with Paclobutrazol( PP333) on the tillering and physiological characteristics of sugarcane seedlings,sugar cane variety ROC22 was used as experimental material. The effects of seed soaking with different concentrations of PP333 were studied. The tiller number and growth of sugarcane were surveyed at the 6-leaf stage,the physiological indicators such as chlorophyll content,soluble protein content,proline content and peroxidase activity were measured at the 2-leaf,4-leaf,and 6-leaf stages. The results showed that the seed soaking with PP333 can effectively improve the tillering of sugarcane seedlings. The suitable concentration for the tillering of sugarcane and the growth and development of sugarcane was of 50 mg/L; the seed soaking with PP333 significantly increased the chlorophyll,soluble protein,proline,and peroxidase activity of leaves of sugarcane seedlings; the content of chlorophyll and soluble protein in leaves of sugarcane seedlings treated with 90 mg/L PP333 was the highest,and the proline content and peroxidase activity of sugarcane treated with 50 mg/L PP333 were the highest.

Chondroitinase ABC treatment of injured spinal cord in rats Evaluation of long-term outcomes

Chondroitin sulfate proteoglycans （CSPGs） which are produced by mature oligodendrocytes and reactive astrocytes can be upregulated after spinal cord injury and contribute to regenerative failure. Chondroitinase ABC （ChABC） digests glycosaminoglycan chains on CSPGs and can thereby overcome CSPG-mediated inhibition. However, many current studies have used an incomplete spinal cord injury model, and examined results after 8-12 weeks of ChABC treatment. In this study, a complete rat spinal cord transection injury model was used to study the long-term effects of ChABC treatment by subarachnoid catheter. Pathology of spinal cord regeneration was compared with control 24 weeks following ChABC treatment using immunohistochemistry and axon tracing techniques. At 24 weeks after injury, neurofilament 200 expression was significantly greater in the ChABC treatment group compared with the transection group. In the ChABC treatment group, axonal growth was demonstrated by a large number of biotinylated dextran amine positive axons caudal to, or past, the epicenter of injury. Biotinylated dextran amine-labeled fibers were found in the proximal end of the spinal cord in the transection alone group. These results confirm that ChABC can promote axon growth, neural regeneration, and repair after spinal cord injury in rats long after the initial injury.

Response of species and stand types to snow/wind damage in a temperate secondary forest,Northeast China

Snow/wind damage is one of the important natural disturbances in forest ecosystems,especially in a montane secondary forest.However,the effects of snow/wind damage remain unclear which affects the management of these forests.Therefore,we investigated the responses of species,individual tree traits and stand structure to snow/wind damage in a montane secondary forest.Results show that,amongst the canopy trees,Betula costata exhibited the most uprooting,bending and overall damage ratio(the number of damaged stems to the total number of stems in a plot); Quercus mongolica showed the highest breakage ratio and Fraxinus mandshurica and Juglans mandshurica the least overall damage ratios.Among the subcanopy trees,Carpinus cordata,Acer mono,Acer tegmentosum and Acer pseudo-sieboldianum showed the least uprooting and breakage,and the most bending damage.A.pseudo-sieboldianum demonstrated the lowest breakage and highest bending damage ratios.Thesefindings indicate that different species have various sensitivities to snow/wind damage.Larger trees(taller,wider crowns) tend to break and become uprooted,while smaller trees are bent or remain undamaged,suggesting that tree characteristics significantly influence the types of damage from snow and wind.Stands of Q.mongolica and B.costata had the highest damage ratios,whereas A.pseudosieboldianum had the lowest snapping ratio.In summary,the severity and type of snow/wind damage are related to individual tree attributes and stand-level characteristics.Therefore,selection of suitable species(e.g.,shorter,smaller with deep root systems,hard wood,bending resistance and compression resistance) and appropriate thinning are recommended for planting in the montane secondary forests.

Assimilation of Doppler Radar Data with an Ensemble 3DEnVar Approach to Improve Convective Forecasting

An ensemble three-dimensional ensemble-variational(3DEnVar)data assimilation(E3DA)system was developed within the Weather Research and Forecasting model’s 3DVar framework to assimilate radar data to improve convective forecasting.In this system,ensemble perturbations are updated by an ensemble of 3DEnVar and the ensemble forecasts are used to generate the flow-dependent background error covariance.The performance of the E3DA system was first evaluated against one experiment without radar DA and one radar DA experiment with 3DVar,using a severe storm case over southeastern China on 5 June 2009.Results indicated that E3DA improved the quantitative forecast skills of reflectivity and precipitation,as well as their spatial distributions in terms of both intensity and coverage over 3DVar.The root-mean-square error of radial velocity from 3DVar was reduced by E3DA,with stronger low-level wind closer to observation.It was also found that E3DA improved the wind,temperature and water vapor mixing ratio,with the lowest errors at the surface and upper levels.3DVar showed moderate improvements in comparison with forecasts without radar DA.A diagnosis of the analysis revealed that E3DA increased vertical velocity,temperature,and humidity corresponding to the added reflectivity,while 3DVar failed to produce these adjustments,because of the lack of reasonable cross-variable correlations.The performance of E3DA was further verified using two convective cases over southern and southeastern China,and the reflectivity forecast skill was also improved over 3DVar.

The associations between multiple circulating biomarkers and the occurrence of atrial fibrillation in hypertrophic cardiomyopathy with or without left ventricular outflow tract obstruction

Objective Atrial fibrillation(AF)is the most common arrhythmia that can portend adverse prognosis in patients with hypertrophic cardiomyopathy(HCM).Data regarding the correlations of different biomarkers and AF in HCM patients are rather limited.In this study,we sought to explore the associations between the occurrence of AF and circulating biomarkers reflecting cardiovascular function(N-terminal pro-Brain natriuretic peptide,NT-proBNP),endothelial function(big endothenlin-1,big ET-1),inflammation(high-sensitivity C-reactive protein,hs-CRP)and myocardial damage(cardiac troponin I,cTnI)in HCM patients with or without left ventricular outflow tract obstruction(LVOTO),respectively.

The Measurement of the Software Ecosystem’s Productivity with GitHub

Software productivity has always been one of the most critical metrics for measuring software development.However,with the open-source community(e.g.,GitHub),new software development models are emerging.The traditional productivity metrics do not provide a comprehensive measure of the new software development models.Therefore,it is necessary to build a productivity measurement model of open source software ecosystem suitable for the open-source community’s production activities.Based on the natural ecosystem,this paper proposes concepts related to the productivity of open source software ecosystems,analyses influencing factors of open source software ecosystem productivity,and constructs a measurement model using these factors.Model validation experiments show that the model is compatible with a large portion of open source software ecosystems in GitHub.This study can provide references for participants of the open-source software ecosystem to choose proper types of ecosystems.The study also provides a basis for ecosystem health assessment for researchers interested in ecosystem quality.

The Knowledge Base Development for the Web Content Accessibility Guidelines

Web Content Accessibility Guideline (WCAG) proposed by Web Accessibility Initiative is the most recognized regulation in the world in evaluating the accessibility of web contents and is one of the W3Cdocumentations. Currently,the WCAG documents are maintained as a non-computable dictionary like resources. In this study, we proposed a methodology to develop an ontological knowledge base with rules for the WCAG 2.0. Two WCAG techniques in different groups of techniques are used to illustrate the creation of the knowledge base and their application programming interfaces. For demonstrating purpose, a web-based WCAG validation system is built. With the proposed knowledge base and interfaces, computer programs can decide whether certain web content satisfies a particular WCAG technique. In other words, the WCAG documents have been successfully trans-formed to a computable recourse. Such sharable knowledge base and programming interfaces can be embedded into any system requiring the WCAG knowledge.

Low-coordination environment design of single Co atoms for efficient CO_(2) photoreduction

Photocatalytic carbon dioxide(CO_(2))to carbon monoxide(CO)offers a promising way for both alleviating the greenhouse effect and meeting the industrial demand.Herein,we constructed a Co single-atom catalyst with intentional low-coordination environment design on porous ZnO(denoted as Co1/ZnO).Impressively,Co1/ZnO exhibited a remarkable activity with a CO yield rate of 22.25 mmol·g^(-1)·h^(-1) and a selectivity of 80.2%for CO_(2) photoreduction reactions under visible light.The incorporation of single Co atoms provided an additional photo-generated electron transfer channel,which suppressed the carrier recombination of photocatalysts.Moreover,the unsaturated Co active sites were capable to adsorb CO_(2) molecule spontaneously,thus facilitating the activation of CO_(2) molecule during CO_(2) reduction course.

碱金属阳离子对硝酸根还原产氨反应的元素依赖性影响

Catalytic conversion of nitrate(NO_(3)^(-))pollutants into ammonia(NH_(3))offers a sustainable and promising route for both wastewater treatment and NH_(3)synthesis.Alkali cations are prevalent in nitrate solutions,but their roles beyond charge balance in catalytic NO_(3)^(-)conversion have been generally ignored.Herein,we report the promotion effect of K^(+)cations in KNO_(3)solution for NO_(3)^(-)reduction over a TiO_(2)-supported Ni single-atom catalyst(Ni_(1)/TiO_(2)).For photocatalytic NO_(3)^(-)reduction reaction,Ni_(1)/TiO_(2)exhibited a 1.9-fold NH_(3)yield rate with nearly 100%selectivity in KNO_(3)solution relative to that in NaNO_(3)solution.Mechanistic studies reveal that the K^(+)cations from KNO_(3)gradually bonded with the surface of Ni_(1)/TiO_(2),in situ forming a K-O-Ni moiety during reaction,whereas the Na^(+)ions were unable to interact with the catalyst in NaNO_(3)solution.The charge accumulation on the Ni sites induced by the incorporation of K atom promoted the adsorption and activation of NO_(3)^(-).Furthermore,the K-O-Ni moiety facilitated the multiple proton-electron coupling of NO_(3)^(-)into NH_(3)by stabilizing the intermediates.

减缓自由阴离子迁移以缓解浓差极化用于高性能的聚合物锂金属电池

Traditional dual-ion lithium salts have been widely used in solid polymer lithium-metal batteries(LMBs).Nevertheless, concentration polarization caused by uncontrolled migration of free anions has severely caused the growth of lithium dendrites. Although single-ion conductor polymers(SICP) have been developed to reduce concentration polarization, the poor ionic conductivity caused by low carrier concentration limits their application. Herein, a dual-salt quasi-solid polymer electrolyte(QSPE), containing the SICP network as a salt and traditional dual-ion lithium salt, is designed for retarding the movement of free anions and simultaneously providing sufficient effective carriers to alleviate concentration polarization. The dual salt network of this designed QSPE is prepared through in-situ crosslinking copolymerization of SICP monomer, regular ionic conductor, crosslinker with the presence of the dual-ion lithium salt,delivering a high lithium-ion transference number(0.75) and satisfactory ionic conductivity(1.16 × 10^(-3) S cm^(-1) at 30 ℃). Comprehensive characterizations combined with theoretical calculation demonstrate that polyanions from SICP exerts a potential repulsive effect on the transport of free anions to reduce concentration polarization inhibiting lithium dendrites. As a consequence, the Li||LiFePO_4 cell achieves a long-cycle stability for 2000 cycles and a 90% capacity retention at 30 ℃. This work provides a new perspective for reducing concentration polarization and simultaneously enabling enough lithiumions migration for high-performance polymer LMBs.

A DNA micro-complex containing polyaptamer for exosome separation and wound healing

Exosomes(EXOs)have showed great potential in regenerative medicine.The separation of EXOs from complex biological media is essential for the down-stream applications.Herein,we report a deoxyribonucleic acid(DNA)-based micro-complex(DMC)containing polyaptamers,which realized the specific separation of EXOs from cell culture media and the significant promotion of wound healing.The synthesis of DMCs was based on a biomineralization process via rolling circle amplification(RCA)under the catalysis of phi29 DNA polymerase.To endow DMCs with the ability to capture EXOs,the DNA template of RCA was integrated with complementary sequence of aptamer that specifically recognized the CD63 proteins on EXOs.The obtained DMCs contained polyaptamers that can specifically capture the EXOs in cell culture media.The EXOs-capturing DMCs were collected by centrifugation,achieving the separation of EXOs.Mesenchymal stem cell(MSC)-derived EXOs(MSC-EXOs)were separated by this DMC-based strategy,and the separated MSC-EXOs significantly enhanced the migration ability of cells.In particular,the significant therapeutic efficacy of the DMCs with MSC-EXOs was verified in full-thickness wound excision mouse models,in which the wounds completely healed in 10 days.We envision that this DMC-based separation strategy can be a promising route to promote the development of EXOs in biomedicine.