Proton exchange membrane water electrolyzers(PEMWEs)are pivotal for efficient hydrogen production due to their high energy efficiency and ability to operate at high current densities,making them ideally suited for int...Proton exchange membrane water electrolyzers(PEMWEs)are pivotal for efficient hydrogen production due to their high energy efficiency and ability to operate at high current densities,making them ideally suited for integration with renewable energy sources.Cobalt(Co)-based nanomaterials,characterized by diverse oxidation states,tunable electronic spin states,and hybrid orbitals,have emerged as promising non-noble metal alternatives to platinum group catalysts for accelerating the anodic oxygen evolution reaction(OER).Based on their inherent properties,this review provides a comprehensive overview of the latest developments in Co-based nanomaterials for acidic OER.The review begins by introducing the operational principles of PEMWEs,the underlying catalytic mechanisms,and the critical design considerations for OER catalysts.It then explores strategies to enhance the activity and stability of Co-based catalysts for acidic OER in PEMWEs,including the incorporation of corrosion-resistant metals or dispersion on acid-resistant supports to increase active surface area and stability;utilization of geometric structural engineering to improve structural integrity and active site efficiency;the optimization of reaction mechanisms to fine-tune catalytic pathways for enhanced stability and performance.The performance degradation mechanisms and metal leaching analysis for Co-based catalysts in PEMWE are also clarified.Finally,this review not only outlines the key challenges associated with Co-based catalysts for acidic OER but also proposes potential strategies to overcome these limitations,offering a roadmap for future advancements and practical implementation of PEMWE technology.展开更多
Grain yield variation has been associated to variation in grain number per unit area(GN).It has been shown in the last about 40 years that GN is linearly associated to the spike dry weight(SDW)at anthesis in wheat,fac...Grain yield variation has been associated to variation in grain number per unit area(GN).It has been shown in the last about 40 years that GN is linearly associated to the spike dry weight(SDW)at anthesis in wheat,fact that has been useful to understand mechanistically potential grain yield.Fruiting efficiency(FE,grains per gram of spike dry weight),the slope between GN and SDW relationship,has been proposed as a possible trait to improve wheat yield potential.The linear relationship between GN and SDW implies a constant increase in GN per unit increase in spike growth and,then a constant FE.However,there are empirical and theoretical elements suggesting that this relationship would not be linear.In this study,we hypothesised and showed that the linearity of the relationship between GN and SDW would be non-linear for extreme values of SDW,implying that the FE would be noticeably reduced at these extreme cases of dry matter allocation to the juvenile spikes.These results have implications for both,genetic and management improvements in grain yield.展开更多
Spiking neural networks(SNNs)represent a biologically-inspired computational framework that bridges neuroscience and artificial intelligence,offering unique advantages in temporal data processing,energy efficiency,and...Spiking neural networks(SNNs)represent a biologically-inspired computational framework that bridges neuroscience and artificial intelligence,offering unique advantages in temporal data processing,energy efficiency,and real-time decision-making.This paper explores the evolution of SNN technologies,emphasizing their integration with advanced learning mechanisms such as spike-timing-dependent plasticity(STDP)and hybridization with deep learning architectures.Leveraging memristors as nanoscale synaptic devices,we demonstrate significant enhancements in energy efficiency,adaptability,and scalability,addressing key challenges in neuromorphic computing.Through phase portraits and nonlinear dynamics analysis,we validate the system’s stability and robustness under diverse workloads.These advancements position SNNs as a transformative technology for applications in robotics,IoT,and adaptive low-power AI systems,paving the way for future innovations in neuromorphic hardware and hybrid learning paradigms.展开更多
Solid oxide fuel cells(SOFCs)are widely presented as a sustainable solution to future energy challenges.Nevertheless,solid oxide fuel cells presently rely on significant use of several critical raw materials to enable...Solid oxide fuel cells(SOFCs)are widely presented as a sustainable solution to future energy challenges.Nevertheless,solid oxide fuel cells presently rely on significant use of several critical raw materials to enable optimized electrode reaction kinetics.This challenge can be addressed by using thinfilm electrode materials;however,this is typically accompanied by complex device fabrication procedures as well as poor mechanical/chemical stability.In this work,we conduct a systematic study of a range of promising thin-film electrode materials based on vertically aligned nanocomposite(VAN)thin films.We demonstrate low area specific resistance(ASR)values of 0.44 cm^(2) at 650℃ can be achieved using(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3)-(Sm_(2)O_(3))_(0.20)(CeO_(2))_(0.80)(LSCF-SDC)thin films,which are also characterized by a low degradation rate,approximately half that of planar LSCF thin films.We then integrate these(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3)-(Sm_(2)O_(3))_(0.20)(CeO_(2))_(0.80) vertically aligned nanocomposite films directly with commercial anode supported half cells through a single-step deposition process.The resulting cells exhibit peak power density of 0.47W cm^(-2) at 750℃,competitive with 0.64W cm^(-2) achieved for the same cells operating with a bulk(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3) cathode,despite 99.5% reduction in cathode critical raw material use.By demonstrating such competitive performance using thin-film cathode functional layers,this work also paves the way for further cost reductions in solid oxide fuel cells,which could be achieved by likewise applying thin-film architectures to the anode functional layer and/or current collecting layers,which typically account for the greatest materials cost in solid oxide fuel cell stacks.Therefore,the present work marks a valuable step towards the sustainable proliferation of solid oxide fuel cells.展开更多
Lithium-sulfur batteries(LSBs)are a promising candidate for next-generation energy storage solutions.However,challenges such as the shuttling effect and sluggish Li-S reaction kinetics of lithium polysulfides hinder t...Lithium-sulfur batteries(LSBs)are a promising candidate for next-generation energy storage solutions.However,challenges such as the shuttling effect and sluggish Li-S reaction kinetics of lithium polysulfides hinder their practical application.In this work,we present a mixed-phase heterostructure comprising Co_(0.85)Se and MoSe_(2),supported on nitrogen-doped carbon polyhedrons(NCP),as an effective sulfur host in the LSB cathode.Through a combination of theoretical calculations and experimental validation,we demonstrate that the Co_(0.85)Se-MoSe_(2)heterointerface significantly enhances electron transfer efficiency,thereby boosting the overall reaction kinetics of the sulfur cathode.As a result,the Co_(0.85)Se-MoSe_(2)/NCP/S electrodes exhibit initial specific capacities exceeding 1500 mAh g^(-1)at 0.1 C and retain 666 m Ah g^(-1)at 3 C,with a capacity fade rate of 0.044%per cycle over 500 cycles at 1.0 C.Notably,even at a high sulfur loading of 3 mg cm^(-2)and a reduced electrolyte volume of 6.7μL mgS^(-1),the Co_(0.85)SeMoSe_(2)/NCP/S electrodes maintain a capacity of 432 mAh g^(-1)after 100 cycles at 0.2 C.展开更多
Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial insemination.While freeze-th...Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial insemination.While freeze-thawing is known to impair sperm DNA integrity,whether the damage induced consists of single-(SSB)or double-strand breaks(DSB)has not been determined.In addition,no previous study has addressed if DNA breaks preferentially reside in specific genome regions such as those forming the toroid linker regions,or are rather spread throughout the regions linked to protamines.The main aim of the present work,therefore,was to elucidate the type and localization of the DNA damage generated by cryopreservation and to evaluate its impact on artificial insemination outcomes in cattle.Results The incidence of SSB and DSB was evaluated in 12 ejaculates before and after cryopreservation with the Comet assay,and the localization of the DNA breaks was assessed using pulsed-field gel electrophoresis(PFGE).Before cryopreservation,the incidence of SSB was 10.99%±4.62%and involved 20.56%±3.04%of sperm cells,whereas these figures significantly(P<0.0001)increased up to 34.11%±3.48%and 53.36%±11.00%in frozen-thawed sperm.In contrast,no significant differences in the incidence of DSB were observed(P>0.990)before and after cryopreservation(before:incidence of 13.91%±1.75%of sperm DNA affecting 56.04%±12.49%of sperm cells;after:incidence of 13.55%±1.55%of sperm DNA involving 53.36%±11.00%of sperm cells).Moreover,PFGE revealed that the percentage of sperm DNA fragments whose length was shorter than a toroid(<31.5 kb)was greater(P<0.0001)after(27.00%±4.26%)than before freeze-thawing(15.57%±4.53%).These differences indicated that the DNA breaks induced by cryopreservation affect the regions condensed in protamines,which are structured in toroids.On the other hand,in vivo fertility rates were associated to the incidence of SSB and DSB in frozen-thawed sperm(P=0.032 and P=0.005),but not with the size of the DNA fragments resulting from these breaks(P>0.05).Conclusion Cryopreservation of bovine sperm generates single-strand DNA breaks,which are mainly located in protamine-condensed toroidal regions.The incidence of DNA breaks in cryopreserved sperm has an impact on cat-tle fertility,regardless of the size of generated fragments.展开更多
The mechanical properties of minerals in planetary materials are not only interesting from a fundamental point of view but also critical to the development of future space missions.Here we present nanoindentation expe...The mechanical properties of minerals in planetary materials are not only interesting from a fundamental point of view but also critical to the development of future space missions.Here we present nanoindentation experiments to evaluate the hardness and reduced elastic modulus of olivine,(Mg,Fe)_(2)SiO_(4),in meteorite NWA 12008,a lunar basalt.Our experiments suggest that the olivine grains in this lunaite are softer and more elastic than their terrestrial counterparts.Also,we have performed synchrotron-based high-pressure X-ray diffraction(HP-XRD)measurements to probe the compressibility properties of olivine in this meteorite and,for comparison purposes,of three ordinary chondrites.The HP-XRD results suggest that the axial compressibility of the orthorhombic b lattice parameter of olivine relative to terrestrial olivine is higher in NWA 12008 and also in the highly-shocked Chelyabinsk meteorite.The origin of the observed differences is discussed.A simple model combining the results of both our nanoindentation and HP-XRD measurements allows us to describe the contribution of macroscopic and chemical-bond related effects,both of which are necessary to reproduce the observed elastic modulus softening.Such joint analysis of the mechanical and elastic properties of meteorites and returned samples opens up a new avenue for characterizing these highly interesting materials.展开更多
Background Despite their low abundance in sperm, mitochondria have diverse functions in this cell type, includ-ing energy production, signalling and calcium regulation. In humans, sperm mitochondrial DNA content(mtDNA...Background Despite their low abundance in sperm, mitochondria have diverse functions in this cell type, includ-ing energy production, signalling and calcium regulation. In humans, sperm mitochondrial DNA content(mtDNAc) has been reported to be negatively linked to sperm function and fertility. Yet, the association between mtDNAc and sperm function in livestock remains unexplored. For this reason, this study aimed to shed some light on the link between mtDNAc and sperm function and fertilising potential in pigs. A qPCR method for mtDNAc quantification was optimised for pig sperm, and the association of this parameter with sperm motility, kinematics, mitochondrial activity, and fertility was subsequently interrogated.Results First, the q PCR method was found to be sensitive and efficient for mtDNAc quantification in pig sperm. By using this technique, mtDNAc was observed to be associated to sperm motility, mitochondrial activity and in vivo, but not in vitro, fertility outcomes. Specifically, sperm with low mtDNAc were seen to exhibit greater motility but decreased mitochondrial activity and intracellular reactive oxygen species. Interestingly, samples with lower mtD-NAc showed higher conception and farrowing rates, but similar in vitro fertilisation rates and embryo development, when compared to those with greater mtDNAc.Conclusions These findings enrich our comprehension of the association of mtDNAc with sperm biology, and lay the foundation for future research into employing this parameter as a molecular predictor for sperm function and fer-tility in livestock.展开更多
Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are essential.This translates into the application of microscale rock mechanics experiments an...Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are essential.This translates into the application of microscale rock mechanics experiments and scanning electron microscopy for surface composition analysis.This study explores the application of Machine Learning algorithms in predicting the mineralogical and mechanical properties of DHOFAR 1084,JAH 838,and NWA 11444 lunar meteorites based solely on their atomic percentage compositions.Leveraging a prior-data fitted network model,we achieved near-perfect classification scores for meteorites,mineral groups,and individual minerals.The regressor models,notably the KNeighbor model,provided an outstanding estimate of the mechanical properties—previously measured by nanoindentation tests—such as hardness,reduced Young’s modulus,and elastic recovery.Further considerations on the nature and physical properties of the minerals forming these meteorites,including porosity,crystal orientation,or shock degree,are essential for refining predictions.Our findings underscore the potential of Machine Learning in enhancing mineral identification and mechanical property estimation in lunar exploration,which pave the way for new advancements and quick assessments in extraterrestrial mineral mining,processing,and research.展开更多
For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions...For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting reaction.Because of the lower thermodynamic requirements to oxidize ammonia compared to water,solar cells with smaller open circuit voltages can provide the required potential for ammonia splitting.In this work,a single perovskite solar cell with an open-circuit potential of 1.08 V is coupled to a 2-electrode electrochemical cell employing hybrid electroanodes functionalized with Ru-based molecular catalysts.The device is active for more than 30 min,producing N_(2) and H_(2) in a 1:2.9 ratio with 89%faradaic efficiency with no external applied bias.This work illustrates that hydrogen production from ammonia can be driven by conventional semiconductors.展开更多
Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separa...Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separate fractions:pre-sperm,sperm-rich(SRF)and post sperm-rich(PSRF).These fractions are known to vary in volume,sperm concentration and quality,as well as in the origin and composition of seminal plasma(SP),with differences being also observed within the SRF one.Yet,whether disparities in the DNA integrity and chromatin condensation and pro-tamination of their sperm exist has not been interrogated.Results This study determined chromatin protamination(Chromomycin A3 test,CMA_(3)),condensation(Dibromobi-mane test,DBB),and DNA integrity(Comet assay)in the pig sperm contained in the first 10 m L of the SRF(SRF-P1),the remaining portion of the sperm-rich fraction(SRF-P2),and the post sperm-rich fraction(PSRF).While chromatin protamination was found to be similar between the different ejaculate fractions(P>0.05),chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF(P=0.018 and P=0.004,respectively).Regarding DNA integrity,no differences between fractions were observed(P>0.05).As the SRF-P1 has the highest sperm concentra-tion and ejaculate fractions are known to differ in antioxidant composition,the oxidative stress index(OSi)in SP,calcu-lated as total oxidant activity divided by total antioxidant capacity,was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF(0.42±0.06 vs.0.23±0.09 and 0.08±0.00,respectively;P<0.01);this index,in addition,was observed to be correlated to the sperm concentration of each fraction(Rs=0.973;P<0.001).Conclusion While sperm DNA integrity was not found to differ between ejaculate fractions,SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the PSRF.This could be related to the OSi of each fraction.展开更多
The commercial viability of thermoelectric(TE)devices relies heavily on two factors:cost reduction and efficiency enhancement.In this study,we first produce p-type Cu_(12)Sb_(4)S_(16-x)(x=0,3,4)using a low-temperature...The commercial viability of thermoelectric(TE)devices relies heavily on two factors:cost reduction and efficiency enhancement.In this study,we first produce p-type Cu_(12)Sb_(4)S_(16-x)(x=0,3,4)using a low-temperature bottom-up approach and demonstrate Cu_(12)Sb_(4)S_(13)to show the best TE performance among the three tested compositions.Subsequently,the TE energy conversion efficiency of Cu_(12)Sb_(4)S_(13)is further enhanced by optimizing its electronic band structure through the incorporation of small amounts of tel-lurium.At an optimal Te content of 5 mol%,more than a twofold increase in the TE figure of merit(zT)is obtained.To gain insight into the mechanism of improvement on the transport properties of the mate-rial,we compare the interphase transport mechanism by incorporating nanodomains of different metals(Ag and Cu)into the Cu_(12)Sb_(4)S_(13)matrix.The improved electrical conductivity obtained with Cu_(12)Sb_(4)S_(13)-Te nanocomposites is attributed to a charge flooding of the Cu_(12)Sb_(4)S_(13)surface.In contrast,excessive down-ward band-bending at the interphases of Ag/Cu metal-semiconductor drastically reduces the electrical conductivity.Besides,a weighted mobility(μw)analysis shows a dominant thermal activation of carri-ers in Cu_(12)Sb_(4)S_(13)-Te nanocomposites.In this material,a strong decrease in lattice thermal conductivity is also found,which is associated with a phonon-carrier scattering mechanism.Our work shows the impor-tance of proper band-engineering in TE nanocomposites to decouple electrical and thermal transport to enhance TE performance,and the efficacy ofμw for electrical and thermal transport analysis.展开更多
This paper introduces a novel fully distributed economic power dispatch(EPD)strategy for distribution networks,integrating dynamic tariffs.A two-layer model is proposed:the first layer comprises the physical power dis...This paper introduces a novel fully distributed economic power dispatch(EPD)strategy for distribution networks,integrating dynamic tariffs.A two-layer model is proposed:the first layer comprises the physical power distribution network,including photovoltaic(PV)sources,wind turbine(WT)generators,energy storage systems(ESS),flexible loads(FLs),and other inflexible loads.The upper layer consists of agents dedicated to communication,calculation,and control tasks.Unlike previous EPD strategies,this approach incorporates dynamic tariffs derived from voltage constraints to ensure compliance with nodal voltage constraints.Addi-tionally,a fast distributed optimization algorithm with an event-triggered communication protocol has been developed to address the EPD problem effectively.Through mathematical and simulation analyses,the proposed algorithm's efficiency and rapid conver-gence capability are demonstrated.展开更多
通过研究由SPIO(superparamagnetic iron oxide)和USPIO(ultrafine SPIO)引起质子的横向弛豫,发现SPIO体系中质子横向弛豫时间(T2)对检测等待时间有很强的依赖性。实验证明只有把等待时间外推到0所得到的T2_0才能够用于T2与浓度间关系...通过研究由SPIO(superparamagnetic iron oxide)和USPIO(ultrafine SPIO)引起质子的横向弛豫,发现SPIO体系中质子横向弛豫时间(T2)对检测等待时间有很强的依赖性。实验证明只有把等待时间外推到0所得到的T2_0才能够用于T2与浓度间关系的研究。最后分析了造成这一现象的原因。展开更多
Breeding has been used successfully for many years in the fruit industry,giving rise to most of today’s commercial fruit cultivars.More recently,new molecular breeding techniques have addressed some of the constraint...Breeding has been used successfully for many years in the fruit industry,giving rise to most of today’s commercial fruit cultivars.More recently,new molecular breeding techniques have addressed some of the constraints of conventional breeding.However,the development and commercial introduction of such novel fruits has been slow and limited with only five genetically engineered fruits currently produced as commercial varieties—virus-resistant papaya and squash were commercialized 25 years ago,whereas insect-resistant eggplant,non-browning apple,and pink-fleshed pineapple have been approved for commercialization within the last 6 years and production continues to increase every year.Advances in molecular genetics,particularly the new wave of genome editing technologies,provide opportunities to develop new fruit cultivars more rapidly.Our review,emphasizes the socioeconomic impact of current commercial fruit cultivars developed by genetic engineering and the potential impact of genome editing on the development of improved cultivars at an accelerated rate.展开更多
Parkinson's disease,the second most prevalent neurodegenerative disorder worldwide,is characterized by a progressive loss of dopaminergic neurons in substantia nigra pars compacta,causing motor symptoms.This disor...Parkinson's disease,the second most prevalent neurodegenerative disorder worldwide,is characterized by a progressive loss of dopaminergic neurons in substantia nigra pars compacta,causing motor symptoms.This disorder's main hallmark is the formation of intraneuronal protein inclusions,named Lewy bodies and neurites.The major component of these arrangements is α-synuclein,an intrinsically disordered and soluble protein that,in pathological conditions,can form toxic and cell-to-cell transmissible amyloid structures.Preventing α-synuclein aggregation has attracted significant effort in the search for a disease-modifying therapy for Parkinson's disease.Small molecules like Synu Clean-D,epigallocatechin gallate,trodusquemine,or anle138 b exemplify this therapeutic potential.Here,we describe a subset of compounds containing a single aromatic ring,like dopamine,ZPDm,gallic acid,or entacapone,which act as molecular chaperones against α-synuclein aggregation.The simplicity of their structures contrasts with the complexity of the aggregation process,yet the block efficiently α-synuclein assembly into amyloid fibrils,in many cases,redirecting the reaction towards the formation of non-toxic off-pathway oligomers.Moreover,some of these compounds can disentangle mature α-synuclein amyloid fibrils.Their simple structures allow structure-activity relationship analysis to elucidate the role of different functional groups in the inhibition of α-synuclein aggregation and fibril dismantling,making them informative lead scaffolds for the rational development of efficient drugs.展开更多
Background:Hospitalized patients recovering from coronavirus disease 2019(COVID-19)may experience disability and suffer from significant physical and mental impairment requiring physical rehabilitation following their...Background:Hospitalized patients recovering from coronavirus disease 2019(COVID-19)may experience disability and suffer from significant physical and mental impairment requiring physical rehabilitation following their discharge.However,to date,no attempt has been made to collate and synthesize literature in this area.Objective:This systematic review examines the outcomes of different physical rehabilitation interventions tested in COVID-19 patients who were discharged from hospital.Search strategy:A systematic search of MEDLINE/PubMed,CINAHL,Scopus and medRxiv was conducted to identify articles published up to March 2022.Inclusion criteria:This systematic review included studies of outpatient rehabilitation programs for people recovering from COVID-19 who received physical activity,exercise,or breathing training to enhance or restore functional capacity,pulmonary function,quality of life,and mental health or function.Data extraction and analysis:Selection of included articles,data extraction,and methodological quality assessments were conducted by two review authors respectively,and consensus was reached through discussion and consultation with a third reviewer.Finally,we review the outcomes of studies based on four categories including:(1)functional capacity,(2)pulmonary function,(3)quality of life,and(4)mental health status.Results:A total of 7534 titles and abstracts were screened;10 cohort studies,4 randomized controlled trials and 13 other prospective studies involving 1583 patients were included in our review.Early physical rehabilitation interventions applied in COVID-19 patients who were discharged from the hospital improved multiple parameters related to functional capacity,pulmonary function,quality of life and mental health status.Conclusion:Physical rehabilitation interventions may be safe,feasible and effective in COVID-19 patients discharged from the hospital,and can improve a variety of clinically relevant outcomes.Further studies are warranted to determine the underlying mechanisms.展开更多
基金financially supported by the National Natural Science Foundation of China(22172063)the Young Taishan Scholars Program(tsqn201812080)+2 种基金the China Scholarship Council(CSC)for scholarship support(202008130132)the Independent Cultivation Program of Innovation Team of Ji’nan City(2021GXRC052)funding from CERCA Programme/Generalitat de Catalunya。
文摘Proton exchange membrane water electrolyzers(PEMWEs)are pivotal for efficient hydrogen production due to their high energy efficiency and ability to operate at high current densities,making them ideally suited for integration with renewable energy sources.Cobalt(Co)-based nanomaterials,characterized by diverse oxidation states,tunable electronic spin states,and hybrid orbitals,have emerged as promising non-noble metal alternatives to platinum group catalysts for accelerating the anodic oxygen evolution reaction(OER).Based on their inherent properties,this review provides a comprehensive overview of the latest developments in Co-based nanomaterials for acidic OER.The review begins by introducing the operational principles of PEMWEs,the underlying catalytic mechanisms,and the critical design considerations for OER catalysts.It then explores strategies to enhance the activity and stability of Co-based catalysts for acidic OER in PEMWEs,including the incorporation of corrosion-resistant metals or dispersion on acid-resistant supports to increase active surface area and stability;utilization of geometric structural engineering to improve structural integrity and active site efficiency;the optimization of reaction mechanisms to fine-tune catalytic pathways for enhanced stability and performance.The performance degradation mechanisms and metal leaching analysis for Co-based catalysts in PEMWE are also clarified.Finally,this review not only outlines the key challenges associated with Co-based catalysts for acidic OER but also proposes potential strategies to overcome these limitations,offering a roadmap for future advancements and practical implementation of PEMWE technology.
基金mainly funded by the State Research Agency of Spain through the Competitive Project PID2021-127415OB-I00 on "Spike fertility in wheat" with some contribution from an AGROTECNIO Seed-funding on "Analysing the physiology of spike density to provide support to selection in breeding programs"RAS did part of the work in this project during a research stay at the Crop Physiology Lab of the University of Lleida co-funded by AUIP (Postgraduate Iberoamerican University Association) grants+1 种基金core funds Crop Physiology Lab of the Ud L. CSC held a Maria Zambrano’s fellowship from the University of Lleida funded by the Spanish Ministry of Universities and the European Social Fund and is a member of CONICET (the Scientific Research Council of Argentina)INTA (the National Institute of Agriculture Technology of Argentina)
文摘Grain yield variation has been associated to variation in grain number per unit area(GN).It has been shown in the last about 40 years that GN is linearly associated to the spike dry weight(SDW)at anthesis in wheat,fact that has been useful to understand mechanistically potential grain yield.Fruiting efficiency(FE,grains per gram of spike dry weight),the slope between GN and SDW relationship,has been proposed as a possible trait to improve wheat yield potential.The linear relationship between GN and SDW implies a constant increase in GN per unit increase in spike growth and,then a constant FE.However,there are empirical and theoretical elements suggesting that this relationship would not be linear.In this study,we hypothesised and showed that the linearity of the relationship between GN and SDW would be non-linear for extreme values of SDW,implying that the FE would be noticeably reduced at these extreme cases of dry matter allocation to the juvenile spikes.These results have implications for both,genetic and management improvements in grain yield.
基金Supported by CUP(J53C22003010006,J43C24000230007)ICREA2019.
文摘Spiking neural networks(SNNs)represent a biologically-inspired computational framework that bridges neuroscience and artificial intelligence,offering unique advantages in temporal data processing,energy efficiency,and real-time decision-making.This paper explores the evolution of SNN technologies,emphasizing their integration with advanced learning mechanisms such as spike-timing-dependent plasticity(STDP)and hybridization with deep learning architectures.Leveraging memristors as nanoscale synaptic devices,we demonstrate significant enhancements in energy efficiency,adaptability,and scalability,addressing key challenges in neuromorphic computing.Through phase portraits and nonlinear dynamics analysis,we validate the system’s stability and robustness under diverse workloads.These advancements position SNNs as a transformative technology for applications in robotics,IoT,and adaptive low-power AI systems,paving the way for future innovations in neuromorphic hardware and hybrid learning paradigms.
基金support from the Royal Academy of Engineering Chair in Emerging technologies(grant number CIET1819_24)the EPSRC Centre of Advanced Materials for Integrated Energy Systems(CAM-IES)(grant number EP/P007767/1)+2 种基金the EU-H2020-ERC-ADG EROS(grant number 882929)support provided by Deutsche Forschungsgemeinschaft(Project no.424789449,grant no.HA1344-45-1)support from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement no.836503.We acknowledge use of the Thermo Fisher Spectra 300 TEM at the Wolfson Electron Microscopy Suite at the University of Cambridge funded by EPSRC under grant EP/R008779/1.
文摘Solid oxide fuel cells(SOFCs)are widely presented as a sustainable solution to future energy challenges.Nevertheless,solid oxide fuel cells presently rely on significant use of several critical raw materials to enable optimized electrode reaction kinetics.This challenge can be addressed by using thinfilm electrode materials;however,this is typically accompanied by complex device fabrication procedures as well as poor mechanical/chemical stability.In this work,we conduct a systematic study of a range of promising thin-film electrode materials based on vertically aligned nanocomposite(VAN)thin films.We demonstrate low area specific resistance(ASR)values of 0.44 cm^(2) at 650℃ can be achieved using(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3)-(Sm_(2)O_(3))_(0.20)(CeO_(2))_(0.80)(LSCF-SDC)thin films,which are also characterized by a low degradation rate,approximately half that of planar LSCF thin films.We then integrate these(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3)-(Sm_(2)O_(3))_(0.20)(CeO_(2))_(0.80) vertically aligned nanocomposite films directly with commercial anode supported half cells through a single-step deposition process.The resulting cells exhibit peak power density of 0.47W cm^(-2) at 750℃,competitive with 0.64W cm^(-2) achieved for the same cells operating with a bulk(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3) cathode,despite 99.5% reduction in cathode critical raw material use.By demonstrating such competitive performance using thin-film cathode functional layers,this work also paves the way for further cost reductions in solid oxide fuel cells,which could be achieved by likewise applying thin-film architectures to the anode functional layer and/or current collecting layers,which typically account for the greatest materials cost in solid oxide fuel cell stacks.Therefore,the present work marks a valuable step towards the sustainable proliferation of solid oxide fuel cells.
基金support from the 2BoSS project of the ERA-MIN3 program with the Spanish grant number PCI2022-132985/AEI/10.13039/501100011033funding from the Generalitat de Catalunya 2021SGR01581 and 2021SGR00457+9 种基金the European Union NextGenerationEU/PRTR,the Natural Science Foundation of Chongqing(No.2023NSCQ-MSX1669)the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJZDK202401110)support of the Supercomputing Center of Lanzhou University,Chinasupported by MCIN with funding from European Union NextGenerationEU(PRTR-C17.I1)by Generalitat de Catalunya(In-CAEM Project)support from the project AMaDE(PID2023-149158OB-C43)funded by MCIN/AEI/10.13039/501100011033/funding from the CSC-UAB PhD scholarship programfunding from Grant IU16-014206(METCAM-FIB)funded by the European Union through the European Regional Development Fund(ERDF)support of the Ministry of Research and Universities,Generalitat de Catalunya。
文摘Lithium-sulfur batteries(LSBs)are a promising candidate for next-generation energy storage solutions.However,challenges such as the shuttling effect and sluggish Li-S reaction kinetics of lithium polysulfides hinder their practical application.In this work,we present a mixed-phase heterostructure comprising Co_(0.85)Se and MoSe_(2),supported on nitrogen-doped carbon polyhedrons(NCP),as an effective sulfur host in the LSB cathode.Through a combination of theoretical calculations and experimental validation,we demonstrate that the Co_(0.85)Se-MoSe_(2)heterointerface significantly enhances electron transfer efficiency,thereby boosting the overall reaction kinetics of the sulfur cathode.As a result,the Co_(0.85)Se-MoSe_(2)/NCP/S electrodes exhibit initial specific capacities exceeding 1500 mAh g^(-1)at 0.1 C and retain 666 m Ah g^(-1)at 3 C,with a capacity fade rate of 0.044%per cycle over 500 cycles at 1.0 C.Notably,even at a high sulfur loading of 3 mg cm^(-2)and a reduced electrolyte volume of 6.7μL mgS^(-1),the Co_(0.85)SeMoSe_(2)/NCP/S electrodes maintain a capacity of 432 mAh g^(-1)after 100 cycles at 0.2 C.
基金Ministry of Science,Innovation and Universities,Spain(NextGeneration EU fundsMaría Zambrano Program 124/MTAI/22+2 种基金and PID2020-113320RB-I00)Agency for Management of University and Research Grants,Regional Government of Catalonia,Spain(2021-SGR-00900)Catalan Institution for Research and Advanced Studies(ICREA).
文摘Background Sperm cryopreservation is widely used in the cattle industry,as it allows for disassociating the localiza-tion of sires and the collection of semen from the timing of artificial insemination.While freeze-thawing is known to impair sperm DNA integrity,whether the damage induced consists of single-(SSB)or double-strand breaks(DSB)has not been determined.In addition,no previous study has addressed if DNA breaks preferentially reside in specific genome regions such as those forming the toroid linker regions,or are rather spread throughout the regions linked to protamines.The main aim of the present work,therefore,was to elucidate the type and localization of the DNA damage generated by cryopreservation and to evaluate its impact on artificial insemination outcomes in cattle.Results The incidence of SSB and DSB was evaluated in 12 ejaculates before and after cryopreservation with the Comet assay,and the localization of the DNA breaks was assessed using pulsed-field gel electrophoresis(PFGE).Before cryopreservation,the incidence of SSB was 10.99%±4.62%and involved 20.56%±3.04%of sperm cells,whereas these figures significantly(P<0.0001)increased up to 34.11%±3.48%and 53.36%±11.00%in frozen-thawed sperm.In contrast,no significant differences in the incidence of DSB were observed(P>0.990)before and after cryopreservation(before:incidence of 13.91%±1.75%of sperm DNA affecting 56.04%±12.49%of sperm cells;after:incidence of 13.55%±1.55%of sperm DNA involving 53.36%±11.00%of sperm cells).Moreover,PFGE revealed that the percentage of sperm DNA fragments whose length was shorter than a toroid(<31.5 kb)was greater(P<0.0001)after(27.00%±4.26%)than before freeze-thawing(15.57%±4.53%).These differences indicated that the DNA breaks induced by cryopreservation affect the regions condensed in protamines,which are structured in toroids.On the other hand,in vivo fertility rates were associated to the incidence of SSB and DSB in frozen-thawed sperm(P=0.032 and P=0.005),but not with the size of the DNA fragments resulting from these breaks(P>0.05).Conclusion Cryopreservation of bovine sperm generates single-strand DNA breaks,which are mainly located in protamine-condensed toroidal regions.The incidence of DNA breaks in cryopreserved sperm has an impact on cat-tle fertility,regardless of the size of generated fragments.
基金Financial support from the project PID2021-128062NB-I00 funded by the Spanish Ministerio de Ciencia,Innovación y Universidades MCIU(doi:10.13039/501100011033)is acknowledged,as well as the Spanish program Unidad de Excelencia María de Maeztu CEX2020-001058-M.The ALBA-CELLS synchrotron is acknowledged for granting beamtime at the MSPD beamline under projects 2021095390 and 2022025734.PG-T acknowledges the financial support from the Spanish MCIU through the FPI predoctoral fellowship PRE2022-104624.JS acknowledges the financial support from projects 2021-SGR-00651 and PID2020-116844RB-C21.EP-A acknowledges financial support from the LUMIO project funded by the Agenzia Spaziale Italiana(2024-6-HH.0).DE thanks the financial support from Spanish MCIU under projects PID2022-138076NB-C41 and RED2022-134388-T from Generalitat Valenciana(GVA)through grants CIPROM/2021/075 and MFA/2022/007,which are part of the Advanced Materials program and is supported with funding from the European Union Next Generation EU(PRTR-C17.I1).RT and DE(PB and DE)thank GVA for the Postdoctoral Fellowship CIAPOS/2021/20(CIAPOS/2023/406).JS-M thanks the Spanish MCIU for the PRE2020-092198 fellowship.NWA 12008 has been studied within the framework of an international European consortium led by IFP.Special acknowledge to I.Weber for providing the NWA 12008 meteorite thin section.This work is part of the doctoral thesis of PG-T(Doctoral Program in Physics at Universitat Autònoma de Barcelona).
文摘The mechanical properties of minerals in planetary materials are not only interesting from a fundamental point of view but also critical to the development of future space missions.Here we present nanoindentation experiments to evaluate the hardness and reduced elastic modulus of olivine,(Mg,Fe)_(2)SiO_(4),in meteorite NWA 12008,a lunar basalt.Our experiments suggest that the olivine grains in this lunaite are softer and more elastic than their terrestrial counterparts.Also,we have performed synchrotron-based high-pressure X-ray diffraction(HP-XRD)measurements to probe the compressibility properties of olivine in this meteorite and,for comparison purposes,of three ordinary chondrites.The HP-XRD results suggest that the axial compressibility of the orthorhombic b lattice parameter of olivine relative to terrestrial olivine is higher in NWA 12008 and also in the highly-shocked Chelyabinsk meteorite.The origin of the observed differences is discussed.A simple model combining the results of both our nanoindentation and HP-XRD measurements allows us to describe the contribution of macroscopic and chemical-bond related effects,both of which are necessary to reproduce the observed elastic modulus softening.Such joint analysis of the mechanical and elastic properties of meteorites and returned samples opens up a new avenue for characterizing these highly interesting materials.
基金funded by the Ministry of Science and Innovation,Spain (AGL2017-88329-R, FPU18/00666 and PID2020-113320RB-I00)the Regional Government of Catalonia,Spain (2017-SGR-1229, 2020-FI-B-00412 and 2020-SGR-0900)the Catalan Institution for Research and Advanced Studies (ICREA)。
文摘Background Despite their low abundance in sperm, mitochondria have diverse functions in this cell type, includ-ing energy production, signalling and calcium regulation. In humans, sperm mitochondrial DNA content(mtDNAc) has been reported to be negatively linked to sperm function and fertility. Yet, the association between mtDNAc and sperm function in livestock remains unexplored. For this reason, this study aimed to shed some light on the link between mtDNAc and sperm function and fertilising potential in pigs. A qPCR method for mtDNAc quantification was optimised for pig sperm, and the association of this parameter with sperm motility, kinematics, mitochondrial activity, and fertility was subsequently interrogated.Results First, the q PCR method was found to be sensitive and efficient for mtDNAc quantification in pig sperm. By using this technique, mtDNAc was observed to be associated to sperm motility, mitochondrial activity and in vivo, but not in vitro, fertility outcomes. Specifically, sperm with low mtDNAc were seen to exhibit greater motility but decreased mitochondrial activity and intracellular reactive oxygen species. Interestingly, samples with lower mtD-NAc showed higher conception and farrowing rates, but similar in vitro fertilisation rates and embryo development, when compared to those with greater mtDNAc.Conclusions These findings enrich our comprehension of the association of mtDNAc with sperm biology, and lay the foundation for future research into employing this parameter as a molecular predictor for sperm function and fer-tility in livestock.
基金EP-A and JMT-R acknowledges financial support from the project PID2021-128062NB-I00 funded by MCIN/AEI/10.13039/501100011033The lunar samples studied here were acquired in the framework of grant PGC2018-097374-B-I00(P.I.JMT-R)+3 种基金This project has received funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation programme(No.865657)for the project“Quantum Chemistry on Interstellar Grains”(QUANTUMGRAIN),AR acknowledges financial support from the FEDER/Ministerio de Ciencia e Innovación-Agencia Estatal de Investigación(No.PID2021-126427NB-I00)Partial financial support from the Spanish Government(No.PID2020-116844RB-C21)the Generalitat de Catalunya(No.2021-SGR-00651)is acknowledgedThis work was supported by the LUMIO project funded by the Agenzia Spaziale Italiana(No.2024-6-HH.0).
文摘Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are essential.This translates into the application of microscale rock mechanics experiments and scanning electron microscopy for surface composition analysis.This study explores the application of Machine Learning algorithms in predicting the mineralogical and mechanical properties of DHOFAR 1084,JAH 838,and NWA 11444 lunar meteorites based solely on their atomic percentage compositions.Leveraging a prior-data fitted network model,we achieved near-perfect classification scores for meteorites,mineral groups,and individual minerals.The regressor models,notably the KNeighbor model,provided an outstanding estimate of the mechanical properties—previously measured by nanoindentation tests—such as hardness,reduced Young’s modulus,and elastic recovery.Further considerations on the nature and physical properties of the minerals forming these meteorites,including porosity,crystal orientation,or shock degree,are essential for refining predictions.Our findings underscore the potential of Machine Learning in enhancing mineral identification and mechanical property estimation in lunar exploration,which pave the way for new advancements and quick assessments in extraterrestrial mineral mining,processing,and research.
基金Financial support from Ministerio de Ciencia e Innovación through projects PID2022-140143OB-I00(MCIN/AEI/10.13039/501100011033)and SO-CEX2019-000925-S(MCIN/AEI/10.13039/5011000110)supported by Marie Sk?odowska-Curie Actions Individual Fellowship grant funding to AMB,grant 101031365-SolTIMEthe support from the MSCA-COFUND I2:ICIQ Impulsion(GA 801474)。
文摘For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting reaction.Because of the lower thermodynamic requirements to oxidize ammonia compared to water,solar cells with smaller open circuit voltages can provide the required potential for ammonia splitting.In this work,a single perovskite solar cell with an open-circuit potential of 1.08 V is coupled to a 2-electrode electrochemical cell employing hybrid electroanodes functionalized with Ru-based molecular catalysts.The device is active for more than 30 min,producing N_(2) and H_(2) in a 1:2.9 ratio with 89%faradaic efficiency with no external applied bias.This work illustrates that hydrogen production from ammonia can be driven by conventional semiconductors.
基金This research was supported by the European Union’s Horizon 2020 research and innovation scheme under the Marie Skłodowska-Curie grant agreement No.801342(Tecniospring INDUSTRYGrant:TECSPR-19-1-0003)+4 种基金the Ministry of Science and Innovation,Spain(Grants:PID2020-113320RB-I00,PID2020-113493RB-I00,RYC2021-034546-I and RYC2021-034764-I)the Catalan Agency for Management of University and Research Grants,Regional Government of Catalonia,Spain(Grants:2017-SGR-1229 and 2021-SGR-00900)the Seneca Foundation,Regional Government of Murcia,Spain(Grant:21935/PI/22)La Marato de TV3 Foundation(Grant:214/857-202039)and the Catalan Institution for Research and Advanced Studies(ICREA).
文摘Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separate fractions:pre-sperm,sperm-rich(SRF)and post sperm-rich(PSRF).These fractions are known to vary in volume,sperm concentration and quality,as well as in the origin and composition of seminal plasma(SP),with differences being also observed within the SRF one.Yet,whether disparities in the DNA integrity and chromatin condensation and pro-tamination of their sperm exist has not been interrogated.Results This study determined chromatin protamination(Chromomycin A3 test,CMA_(3)),condensation(Dibromobi-mane test,DBB),and DNA integrity(Comet assay)in the pig sperm contained in the first 10 m L of the SRF(SRF-P1),the remaining portion of the sperm-rich fraction(SRF-P2),and the post sperm-rich fraction(PSRF).While chromatin protamination was found to be similar between the different ejaculate fractions(P>0.05),chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF(P=0.018 and P=0.004,respectively).Regarding DNA integrity,no differences between fractions were observed(P>0.05).As the SRF-P1 has the highest sperm concentra-tion and ejaculate fractions are known to differ in antioxidant composition,the oxidative stress index(OSi)in SP,calcu-lated as total oxidant activity divided by total antioxidant capacity,was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF(0.42±0.06 vs.0.23±0.09 and 0.08±0.00,respectively;P<0.01);this index,in addition,was observed to be correlated to the sperm concentration of each fraction(Rs=0.973;P<0.001).Conclusion While sperm DNA integrity was not found to differ between ejaculate fractions,SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the PSRF.This could be related to the OSi of each fraction.
基金Dr.K.H.Lim acknowledges the financial support of the National Natural Science Foundation of China(Grant No.22208293)Research Funds of the Institute of Zhejiang University-Quzhou(Nos.IZQ2021RCZX003,IZQ2021RCZX002,IZQ2021KJ2024,IZQ2022KYZX09)+3 种基金supported by the State Key Laboratory of Fluorinated Greenhouse gases Replacement and Treatment(No.SKLFGGRT2022001)the State Key Laboratory of Electrical Insulation and Power Equipment(No.EIPE23201)Dr.Y.Liu acknowledges funding from the National Natural Science Foundation of China(NSFC)(Grants No.22209034)the Innovation and Entrepreneurship Project of Overseas Returnees in Anhui Province(Grants No.2022LCX002)。
文摘The commercial viability of thermoelectric(TE)devices relies heavily on two factors:cost reduction and efficiency enhancement.In this study,we first produce p-type Cu_(12)Sb_(4)S_(16-x)(x=0,3,4)using a low-temperature bottom-up approach and demonstrate Cu_(12)Sb_(4)S_(13)to show the best TE performance among the three tested compositions.Subsequently,the TE energy conversion efficiency of Cu_(12)Sb_(4)S_(13)is further enhanced by optimizing its electronic band structure through the incorporation of small amounts of tel-lurium.At an optimal Te content of 5 mol%,more than a twofold increase in the TE figure of merit(zT)is obtained.To gain insight into the mechanism of improvement on the transport properties of the mate-rial,we compare the interphase transport mechanism by incorporating nanodomains of different metals(Ag and Cu)into the Cu_(12)Sb_(4)S_(13)matrix.The improved electrical conductivity obtained with Cu_(12)Sb_(4)S_(13)-Te nanocomposites is attributed to a charge flooding of the Cu_(12)Sb_(4)S_(13)surface.In contrast,excessive down-ward band-bending at the interphases of Ag/Cu metal-semiconductor drastically reduces the electrical conductivity.Besides,a weighted mobility(μw)analysis shows a dominant thermal activation of carri-ers in Cu_(12)Sb_(4)S_(13)-Te nanocomposites.In this material,a strong decrease in lattice thermal conductivity is also found,which is associated with a phonon-carrier scattering mechanism.Our work shows the impor-tance of proper band-engineering in TE nanocomposites to decouple electrical and thermal transport to enhance TE performance,and the efficacy ofμw for electrical and thermal transport analysis.
文摘This paper introduces a novel fully distributed economic power dispatch(EPD)strategy for distribution networks,integrating dynamic tariffs.A two-layer model is proposed:the first layer comprises the physical power distribution network,including photovoltaic(PV)sources,wind turbine(WT)generators,energy storage systems(ESS),flexible loads(FLs),and other inflexible loads.The upper layer consists of agents dedicated to communication,calculation,and control tasks.Unlike previous EPD strategies,this approach incorporates dynamic tariffs derived from voltage constraints to ensure compliance with nodal voltage constraints.Addi-tionally,a fast distributed optimization algorithm with an event-triggered communication protocol has been developed to address the EPD problem effectively.Through mathematical and simulation analyses,the proposed algorithm's efficiency and rapid conver-gence capability are demonstrated.
文摘通过研究由SPIO(superparamagnetic iron oxide)和USPIO(ultrafine SPIO)引起质子的横向弛豫,发现SPIO体系中质子横向弛豫时间(T2)对检测等待时间有很强的依赖性。实验证明只有把等待时间外推到0所得到的T2_0才能够用于T2与浓度间关系的研究。最后分析了造成这一现象的原因。
文摘Breeding has been used successfully for many years in the fruit industry,giving rise to most of today’s commercial fruit cultivars.More recently,new molecular breeding techniques have addressed some of the constraints of conventional breeding.However,the development and commercial introduction of such novel fruits has been slow and limited with only five genetically engineered fruits currently produced as commercial varieties—virus-resistant papaya and squash were commercialized 25 years ago,whereas insect-resistant eggplant,non-browning apple,and pink-fleshed pineapple have been approved for commercialization within the last 6 years and production continues to increase every year.Advances in molecular genetics,particularly the new wave of genome editing technologies,provide opportunities to develop new fruit cultivars more rapidly.Our review,emphasizes the socioeconomic impact of current commercial fruit cultivars developed by genetic engineering and the potential impact of genome editing on the development of improved cultivars at an accelerated rate.
文摘Parkinson's disease,the second most prevalent neurodegenerative disorder worldwide,is characterized by a progressive loss of dopaminergic neurons in substantia nigra pars compacta,causing motor symptoms.This disorder's main hallmark is the formation of intraneuronal protein inclusions,named Lewy bodies and neurites.The major component of these arrangements is α-synuclein,an intrinsically disordered and soluble protein that,in pathological conditions,can form toxic and cell-to-cell transmissible amyloid structures.Preventing α-synuclein aggregation has attracted significant effort in the search for a disease-modifying therapy for Parkinson's disease.Small molecules like Synu Clean-D,epigallocatechin gallate,trodusquemine,or anle138 b exemplify this therapeutic potential.Here,we describe a subset of compounds containing a single aromatic ring,like dopamine,ZPDm,gallic acid,or entacapone,which act as molecular chaperones against α-synuclein aggregation.The simplicity of their structures contrasts with the complexity of the aggregation process,yet the block efficiently α-synuclein assembly into amyloid fibrils,in many cases,redirecting the reaction towards the formation of non-toxic off-pathway oligomers.Moreover,some of these compounds can disentangle mature α-synuclein amyloid fibrils.Their simple structures allow structure-activity relationship analysis to elucidate the role of different functional groups in the inhibition of α-synuclein aggregation and fibril dismantling,making them informative lead scaffolds for the rational development of efficient drugs.
文摘Background:Hospitalized patients recovering from coronavirus disease 2019(COVID-19)may experience disability and suffer from significant physical and mental impairment requiring physical rehabilitation following their discharge.However,to date,no attempt has been made to collate and synthesize literature in this area.Objective:This systematic review examines the outcomes of different physical rehabilitation interventions tested in COVID-19 patients who were discharged from hospital.Search strategy:A systematic search of MEDLINE/PubMed,CINAHL,Scopus and medRxiv was conducted to identify articles published up to March 2022.Inclusion criteria:This systematic review included studies of outpatient rehabilitation programs for people recovering from COVID-19 who received physical activity,exercise,or breathing training to enhance or restore functional capacity,pulmonary function,quality of life,and mental health or function.Data extraction and analysis:Selection of included articles,data extraction,and methodological quality assessments were conducted by two review authors respectively,and consensus was reached through discussion and consultation with a third reviewer.Finally,we review the outcomes of studies based on four categories including:(1)functional capacity,(2)pulmonary function,(3)quality of life,and(4)mental health status.Results:A total of 7534 titles and abstracts were screened;10 cohort studies,4 randomized controlled trials and 13 other prospective studies involving 1583 patients were included in our review.Early physical rehabilitation interventions applied in COVID-19 patients who were discharged from the hospital improved multiple parameters related to functional capacity,pulmonary function,quality of life and mental health status.Conclusion:Physical rehabilitation interventions may be safe,feasible and effective in COVID-19 patients discharged from the hospital,and can improve a variety of clinically relevant outcomes.Further studies are warranted to determine the underlying mechanisms.
