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Effect of rare-earth oxides on properties of silicon nitride obtained by normal sintering and sinter-HIp

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Journal of Rare Earths 2012年第11期30卷 1177-1183页

作者： Cecilia C.Guedes-silva Flávio Machado de Souza Carvalho josé Carlos bressiani Nuclear and Energy Research Institute-IpEN/CNEN Geoscience Institute-IGC/USp

This paper presented the microstructure, mechanical properties and oxidation behavior of silicon nitride obtained by both conventional sintering and sintering followed by hot isostatic pressing （HIp）. Silicon nitride with additives such as 5 wt.% Al2O3 and 5 wt.% Ln203 （Ln= La, La concentrate, Gd or La＋Gd） were studied. The results revealed that Gd203 additions increased the formation of elongated grains of β-Si3N4, the fracture toughness and oxidation resistance. La2O3 additions led to higher densification and hardness values, while addition of La2O3 concentrate promoted the formation of materials with intermediate properties, compared to the other studied compositions. Hot isostatic pressing increased the hardness but decreased the fracture toughness of the material, mainly because it allowed residual pores to close and also reduced the average aspect ratio of β-Si3N4 grains.

关键词： rare earths silicon nitride properties normal sintering sinter-HIp

Traits uncover quasi-neutral community assembly in a coastal heath vegetation

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Journal of plant Ecology 2019年第4期12卷 703-712页

作者： joséLuiz Alves silva Alexandre Fadigas Souza Louis Stephen Santiago programa de pós-Graduação em Ecologia Departamento de EcologiaUniversidade Federal do Rio Grande do NorteNatal 59078-970Brazil Departamento de Ecologia Universidade Federal do Rio Grande do NorteNatal 59078-970Brazil Department of botany and plant Sciences University of California2150 Batchelor HallRiversideCA 92521USA Smithsonian Tropical Research Institute BalboaAncónPanamáRepublic of Panamá

Aims Trait-based approaches are increasingly being used in ecology due to their potential to explain and predict community structure and dynamic regardless of species ***,we asked whether coastal heath vegetation established in stressful habitats could be assembled by quasi-neutral mechanisms based on functional trait *** are organized through quasi-neutral dynamics if abiotic gradients and/or species interactions impose sorting on functional traits and species performances,but not on species phylogenetic relatedness and *** The study was conducted in a coastal area containing tall dunes near the sea,and relatively flat areas punctuated by short palaeodunes further inland,Northeastern South *** evaluated 10 traits of the 21 most abundant species,as well as eight abiotic variables in 70 plots(25 m^(2))established in dune tops,valleys,flat and steep *** effect of environmental filter was tested by linear mixed models(LMM)between each community-weighted mean(CWM)trait and the abiotic variables,and by two indices of environmental filtering based on intra-and interspecific-trait vari-ability relative to null *** evaluate the effect of species inter-actions,we used an index of niche overlap relative to null models,and LMMs between this index and the species richness of *** Findings The environmental filtering index did not deviate from null expect-ations for any *** that included individual variability per-formed similarly to models that used species mean ***,the explicit consideration of environmental gradients by CWM ana-lyses revealed functional patterns that would remain undetected if trait distribution was analyzed *** addition,intraspecific vari-ation in the stem length was an important driver of species diversity as suggested by the relationship between species richness and the niche overlap *** on the occurrence and phylogenetic re-latedness o

关键词： Restinga heath vegetation harsh environment stress-tolerant species response traits

Cell-based therapeutic strategies for treatment of spinocerebellar ataxias:an update

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Neural Regeneration Research 2023年第6期18卷 1203-1212页

作者： Joana Sofia Correia Sara Duarte-silva António joséSalgado patrícia Maciel Life and Health Sciences Research Institute(ICVS) School of MedicineUniversity of MinhoBragaPortugal ICVS/3b’s–pT Government Associate Laboratory BragaGuimarãesPortugal

Spinocerebellar ataxias are heritable neurodegenerative diseases caused by a cytosine-adenine-guanine expansion,which encodes a long glutamine tract(polyglutamine)in the respective wild-type protein causing misfolding and protein *** features of polyglutamine spinocerebellar ataxias include neuronal aggregation,mitochondrial dysfunction,decreased proteasomal activity,and autophagy *** polyglutamine protein aggregates accumulate within neurons and cause neural dysfunction and death in specific regions of the central nervous *** ataxias are mostly characterized by progressive ataxia,speech and swallowing problems,loss of coordination and gait *** the past decade,efforts have been made to ameliorate disease symptoms in patients,yet no cure is *** studies have been proposing the use of stem cells as promising tools for central nervous system tissue *** far,pre-clinical trials have shown improvement in various models of neurodegenerative diseases following stem cell transplantation,including animal models of spinocerebellar ataxia types 1,2,and ***,contrasting results can be found in the literature,depending on the animal model,cell type,and route of administration ***,clinical trials using cellular implants into degenerated brain regions have already been applied,with the expectation that these cells would be able to differentiate into the specific neuronal subtypes and re-populate these regions,reconstructing the affected neural ***,the question of how feasible it is to continue such treatments remains unanswered,with long-lasting effects being still *** establish the value of these advanced therapeutic tools,it is important to predict the actions of the transplanted cells as well as to understand which cell type can induce the best outcomes for each *** studies are needed to determine the best route of administration,without neglec

关键词： cell transplantation engraftment induced pluripotent stem cells mesenchymal stem cells neural progenitor cells neuroprotection polyglutamine spinocerebellar ataxias secretome spinocerebellar ataxia stem cell therapy

How far have we come?Review of main public policies to reduce landslide impacts in brazil

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Journal of Mountain Science 2024年第9期21卷 2891-2904页

作者： bianca Carvalho VIEIRA Tiago Damas MARTINS Telma Mendes da silva joséEduardo bONINI Department of Geography University of São PauloAvenida Professor Lineu Prestes 05508-000Brazil Cities Institute Federal University of São PauloAvenida Jacu-Pêssego 08260-001Brazil Department of Geography Federal University of Rio de JaneiroAvenida Athos da Silveira Ramos 21941-916Brazil

During the rainy season in brazil,landslides can have catastrophic consequences,including loss of life,damage to urban infrastructure and significant economic ***,more than eight million people in brazil live in disaster-prone *** objective of this article is to present a chronological review of the principal policies and programmes at the national,state,and municipal levels,with an emphasis on their key actions aimed at mitigating the impact of disasters related to natural hazards,particularly *** analysis was based on official records of public policies from the national,state,and municipal *** results show that several initiatives were initially developed at the local and regional ***,it was not until the late 1980s that a comprehensive organisation of civil protection at the national level emerged as a response *** is possible to highlight three phases(understanding,coexistence,and prevention)of institutional action focused on risk management in the face of *** the growing knowledge of risk scenarios,disasters continue to occur in brazil on an annual basis,revealing several obstacles to reducing their impact,particularly given the social and economic disparities between brazilian regions and the applicability of public policies that must overcome the limitations of each municipality.

关键词： Disasters Risk Mitigation prevention Legislation Civil Defense Natural Hazards

Novel therapeutic strategies targeting mitochondria as a gateway in neurodegeneration

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Neural Regeneration Research 2023年第5期18卷 991-995页

作者： Diogo Trigo jose Joao Vitoria Odete A.b.da Cruz e silva Neuroscience and Signalling Laboratory Institute of Biomedicine(iBiMED)Department of Medical SciencesUniversity of AveiroAveiroPortugal

In recent years, multiple disciplines have focused on mitochondrial biology and contributed to understanding its relevance towards adult-onset neurodegenerative disorders. These are complex dynamic organelles that have a variety of functions in ensuring cellular health and homeostasis. The plethora of mitochondrial functionalities confers them an intrinsic susceptibility to internal and external stressors(such as mutation accumulation or environmental toxins), particularly so in long-lived postmitotic cells such as neurons. Thus, it is reasonable to postulate an involvement of mitochondria in aging-associated neurological disorders, notably neurodegenerative pathologies including Alzheimer’s disease and parkinson’s disease. On the other hand, biological effects resulting from neurodegeneration can in turn affect mitochondrial health and function, promoting a feedback loop further contributing to the progression of neuronal dysfunction and cellular death. This review examines state-of-the-art knowledge, focus on current research exploring mitochondrial health as a contributing factor to neuroregeneration, and the development of therapeutic approaches aimed at restoring mitochondrial homeostasis in a pathological setting.

关键词： Alzheimer’s disease axon energy homeostasis glymphatic system mitochondria mitostasis neurodegeneration neuroregeneration parkinson’s disease therapeutical strategies

Anchor Root Development: A World within Worlds

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Molecular plant 2020年第8期13卷 1105-1107页

作者： joséManuel pérez-pérez Instituto de bioingeniería Universidad Miguel Hernández03202 ElcheSpain

Many plant species develop shoot-borne adventitious roots(ARs)with specialized functions that contribute to plant adaptability by enhancing resource capture and stress *** Arabidopsis,as in many dicots,the postembryonic root system is primarily composed of lateral roots(LRs),which originate from the xylem pole pericycle cells through a process that involves periodic oscillation in gene expression mediated by a β-carotenoidderived signal(Dickinson et al.,2019).Our understanding of the key molecular and signaling events regulating AR initiation has recently been obtained from studies in Arabidopsis,where ARs are formed on etiolated hypocotyls upon transfer to light(Lakehal et al.,2019)or from excised leaf explants(Zhang et al.,2019).Anchor roots(ANRs)are a type of AR that originate immediately below the root-hypocotyl junction in an auxindependent manner and that require a diapocarotenoid-derived signal(anchorene)to emerge(Jia et al.,2019).ANR primordia activation may represent a generic mechanism to compensate for the loss of the growth potential of the primary root(pR),as it is enhanced by mutations affecting pR growth,by whole-root excision or by nitrogen deficiency(Jia et al.,2019).A recent paper by bai et al.(2020)provides direct evidence that a regulatory module involving the Ap2/ERF transcription factor AbSCISIC ACID INSENSITIVE 4(AbI4),the mitogen-activated protein kinases(MApKs)MpK3 and MpK6,and the phosphatase pp2C12 controls ANR emergence in Arabidopsis.

关键词： roots Arabidopsis Root

Effectiveness of different biochars in remediating a salt-affected Luvisol in Northeast brazil

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biochar 2021年第2期3卷 149-159页

作者： Wallace Melo dos Santos Maria Isidoria silva Gonzaga joséAiron da silva AndréQuintão de Almeida joséCarlos de Jesus Santos Thomas Antonio silva Gonzaga Idamar da silva Lima EloáMoura Araújo Water Resources Graduate program Federal University of SergipeSão CristóvãoSE 49100‑000Brazil Agronomy Department Federal University of SergipeSão CristóvãoSE 49100‑000Brazil Agriculture Engineering Department Federal University of SergipeSão CristóvãoSE 49100‑000Brazil University of Notre Dame Notre DameIN 46556USA Soils and Agricultural Engineering Department Federal University of ParanáCuritibaPR 80060‑000Brazil

biochar has been proposed as a soil amendment to reclaim salt-affected ***,the evaluation of the different biochar types in these soils is essential due to the significant variation among biochar *** this study,biochars from sugarcane bagasse(Sb),orange bagasse(Ob),and corncob(Cb)were applied alone and in the presence of gypsum(G)to test their potential to remediate a highly degraded saline-sodic soil in brazil´s Northeast *** that,we conducted a laboratory column-leaching experiment and a greenhouse *** the column-leaching test,we analyzed the sodium adsorption ratio(SAR),the electrical conductivity of the saturation extract(ECe),the concentrations of major ions,and the exchangeable sodium percentage(ESp).Maize plants were grown in the leached soil in a ***-and corncob-derived biochars were more efficient than gypsum in reducing the soil salinity,bringing the indicators below threshold values,and optimizing soil reclamation *** ECe,SAR,and ESp were reduced to 3.42 dS m−1,1.64(mmolc dm−3)0.5 and 4.86%,respectively,in the Sb treatment;and to 3.19 dS m−1,0.88(mmolc dm−3)0.5 and 2.53%,respectively,in the Cb *** bagasse biochar did not effectively reduce the salinity *** biochar treatments improved seed germination and plant *** Sb,Cb,SbG,and CbG treatments increased plant height(478–558%),shoot mass(783–983%),and root mass(386–500%),***,the application of Sb and Cb is an effective alternative to remediate saline-sodic soils and to reduce the impact of soil salinity in the environment.

关键词： biochar Soil remediation Soil salinity Corn growth

Disaster Journalism in print Media:Analysis of the Top 10 Hydrogeomorphological Disaster Events in portugal,1865–2015

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International Journal of Disaster Risk Science 2022年第4期13卷 521-535页

作者： Michele Nacif Antunes Susana da silva pereira joséLuis Zêzere Adauto Emmerich Oliveira postgraduate program in public Health(ppGSC) Federal University of Espírito SantoVitoriaEspírito Santo 29047-105Brazil Centre for Geographical Studies Institute of Geography and Spatial PlanningUniversidade de Lisboa1600-276 LisbonPortugal Associate Laboratory TERRA 1349-017 LisbonPortugal

Disaster communication guidelines emphasize that journalists should be aware of past major disasters and draw lessons from the coverage of those *** press is an important source for the evolution of historical disaster and risk research paradigms over *** study explored the top 10 damaging hydrogeomorphological events in portugal selected from the disaster database,which includes events that caused human damages(fatalities,injured,missing,evacuated,and displaced)reported over a period of 151years(1865–2015)by the portuguese newspaper Diário de Notícias(DN).News analysis was guided by the news *** analysis of the news published in DN enabled us to identify textual marks that present interconnections in the journalistic coverage and produce discursive standards for these *** textual marks were associated with the hazard and risk *** discursive standards of DN did not clearly reflect the ruptures in the hazard *** a rule,the journalistic reports contributed to the naturalization of disasters and the gap in public understanding of risks,by presenting an approach focused on relief actions—ignoring social issues,vulnerability,and population resilience—reducing the discourse of preparedness for future disasters.

关键词： Disaster journalism Hydrogeomorphological events News protocol portugal print media

Intranasal delivery of nanostructured lipid carriers,solid lipid nanoparticles and nanoemulsions:A current overview of in vivo studies

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Acta pharmaceutica Sinica b 2021年第4期11卷 925-940页

作者： Cláudia pina Costa Joao Nuno Moreira joséManuel Sousa Lobo Ana Catarina silva UCIbIO/REQUIMTE MedtechLaboratory of Pharmaceutical TechnologyDepartment of Drug SciencesFaculty of PharmacyUniversity of PortoPorto 4050-313Portugal CNC-Center for Neuroscience and Cell biology Center for Innovative Biomedicine and Biotechnology(CIBB)University of CoimbraFaculty of Medicine(Pólo I)Coimbra 3004-504Portugal UC-University of Coimbra CIBBFaculty of PharmacyPólo Das Ciências da SaúdeCoimbra 3000-548Portugal Fp-ENAS(UFp Energy Environment and Health Research Unit)CEBIMED(Biomedical Research Centre)Faculty of Health SciencesUniversity Fernando PessoaPorto 4249-004Portugal

The management of the central nervous system(CNS)disorders is challenging,due to the need of drugs to cross the blood-brain barrier(bbb)and reach the *** the various strategies that have been studied to circumvent this challenge,the use of the intranasal route to transport drugs from the nose directly to the brain has been showing promising *** addition,the encapsulation of the drugs in lipid-based nanocarriers,such as solid lipid nanoparticles(SLNs),nanostructured lipid carriers(NLCs)or nanoemulsions(NEs),can improve nose-to-brain transport by increasing the bioavailability and site-specifc *** review provides the state-of-the-art of in vivo studies with lipid-based nanocarriers(SLNs,NLCs and NEs)for nose-to-brain *** on the literature available from the past two years,we present an insight into the different mechanisms that drugs can follow to reach the brain after intranasal *** results of pharmacokinetic and pharmacodynamics studies are reported and a critical analysis of the differences between the anatomy of the nasal cavity of the different animal species used in in vivo studies is carried *** the exact mechanism of drug transport from the nose to the brain is not fully understood and its effectiveness in humans is unclear,it appears that the intranasal route together with the use of NLCs,SLNs or NEs is advantageous for targeting drugs to the *** systems have been shown to be more effective for nose-to-brain delivery than other routes or formulations with non-encapsulated drugs,so they are expected to be approved by regulatory authorities in the coming years.

关键词： Nose-to-brain delivery Intranasal administration Nanostructured lipid carriers NLC Solid lipid nanoparticles SLN Nanoemulsions In vivo studies pharmacokinetic pharmacodynamics