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Structural metamaterials with negative mechanical/thermomechanical indices: A review

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Progress in Natural Science:Materials International 2021年第6期31卷 801-808页

作者： jo?o o.Cardoso jo?o Paulo Borges Alexandre Velhinho CENIMAT/i3N Departamento de Ciência dos Materiais Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa

Structural metamaterials presenting negative values of one or more mechanical and thermomechanical indices–namely the Poisson's ratio, the linear compressibility, and the coefficient of thermal expansion – are the promising candidates to the applications in many fields, ranging from precision mechanics to biomedical devices or energy absorption. Although scattered mentions may be found in the literature since the late eighties of 20th century, the systematic research efforts concerning these materials became effective much later. The present work is to review the main scientific contributions to the topic in the last five years. This paper first deals with those metamaterials showing a single negative index, and then proceeds to analyze the much less frequent instances of coupled negative indices, with emphasis on the so-called anepectic case, which exhibits an unusual thermomechanical response.

关键词： Mechanical and thermomechanical metamaterials Auxetic Anepectic Negative Poisson's ratio Negative thermal expansion Negative linear compressibility

A Quasilinear System Related with the Asymptotic Equation of the Nematic Liquid Crystal’s Director Field

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Chinese Annals of Mathematics,Series B 2021年第2期42卷 163-172页

作者： joão-Paulo DIAS Departamento de Matemática and CMAFcIo Faculdade de Ciências da Universidade de LisboaCampo GrandeEdificio C61749-016 LisboaPortugal

In this paper, the author studies the local existence of strong solutions and their possible blow-up in time for a quasilinear system describing the interaction of a short wave induced by an electron field with a long wave representing an extension of the motion of the director field in a nematic liquid crystal’s asymptotic model introduced in[Saxton, R. A., Dynamic instability of the liquid crystal director. In: Current Progress in Hyperbolic Systems(Lindquist, W. B., ed.), Contemp. Math., Vol.100, Amer. ***., Providence, RI, 1989, pp.325–330] and [Hunter, J. K. and Saxton, R. A., Dynamics of director fields, SIAM J. Appl. Math., 51, 1991, 1498–1521] and studied in [Hunter, J. *** Zheng, Y., on a nonlinear hyperbolic variational equation I, Arch. Rat. Mech. Anal.,129, 1995, 305–353], [Hunter, J. K. and Zheng, Y., on a nonlinear hyperbolic variational equation II, Arch. Rat. Mech. Anal., 129, 1995, 355–383] and in [Zhang, P. and Zheng,Y., on oscillation of an asymptotic equation of a nonlinear variational wave equation,Asymptotic Anal., 18, 1998, 307–327] and, more recently, in [Bressan, A., Zhang, P. and Zheng, Y., Asymptotic variational wave equations, Arch. Rat. Mech. Anal., 183, 2007,163–185].

关键词： Benney system Conservation law Schrödinger equation Nematic liquid crystal Director field

Vertical stratification of bat assemblages in flooded and unflooded Amazonian forests

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Current Zoology 2010年第4期56卷 469-478页

作者： Maria joo Ramos PEREIRA joo Tiago MARQUES jorge M.PALMEIRIM Centro de Biologia Ambiental Departamento de Biologia Animal Faculdade de Ciências da Universidade de Lisboa Instituto de Desenvolvimento Sustentvel Mamirau

Tropical rainforests usually have multiple strata that results in a vertical stratification of ecological opportunities foranimals. We investigated if this stratification influences the way bats use the vertical space in flooded and unflooded forests of theCentral Amazon. Using mist-nets set in the canopy (17 to 35 m high) and in the understorey (0 to 3 m high) we sampled four sitesin upland unflooded forests (terra firme), three in forests seasonally flooded by nutrient-rich water (varzea), and three in forestsseasonally flooded by nutrient-poor water (igapo). Using rarefaction curves we found that species richness in the understorey andcanopy were very similar. An ordination analysis clearly separated the bat assemblages of the canopy from those of the understorey inboth flooded and unflooded habitats. Gleaning carnivores were clearly associated with the understorey, whereas frugivores wereabundant in both strata. of the frugivores, Carollinae and some Stenodermatinae were understorey specialists, but several Stenodermatinaemostly used the canopy. The first group mainly includes species that, in general, feed on fruits of understorey shrubs,whereas the second group feed on figs and other canopy fruits. We conclude that vertical stratification in bat communities occurseven within forests with lower canopy heights, such as Amazonian seasonally flooded forests, and that the vertical distribution ofbat species is closely related to their diet and foraging behaviour.

关键词： Amazon Bats Chiroptera Vertical stratification Floodplain

Evolution of forest cover in Portugal: A review of the 12th–20th centuries

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journal of Forestry Research 2014年第2期25卷 249-256页

作者： Fernando Reboredo joo Pais Universidade Nova de Lisboa Faculdade de Ciências e TecnologiaCICEGeDepartmento de Ciências da Terra

Portugal＇s forests in the 12th century were dominated by the Fagaceae represented by Quercus and Castanea, and several pine species From the 12th century onwards, forests underwent changes in their management starting with protection and ultimately leading to intense exploitation. The massive naval construction during the maritime expansion （mainly in the 15th-16th centuries） involved felling of approximately 5 million trees mainly Quercus suber, Pinus pinea and other Quercus species. Cumulative fuel-wood consumption of 959 Mm3 during 1300-1854 was attributed to demographic expansion while the deforestation rate during 1636-1854 accounted for a minimum of 72.6% and a maximum of 96% of total forest cover. The volume of timber used in railway sleepers from 1856 onwards might have reached 0.5 Mm3. The last quarter of the 20th century increased the forest cover of Portugal through the World Bank program of Eucalyptus globulus reforestation.

关键词： forest cover change forest exploitation forest economics Portugal.

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural Regeneration Research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam M.R.Groh moein Yaqubi Qiao-Ling Cui jo Anne Stratton G.R.Wayne moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

Biotechnology of the multipurpose tree species Arbutus unedo:a review

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journal of Forestry Research 2022年第2期33卷 377-390页

作者： joão Martins Glória Pinto jorge Canhoto Centre for Functional Ecology Department of Life SciencesUniversity of CoimbraCoimbraPortugal Centre for Environmental and Marine Studies Department of BiologyUniversity of AveiroAveiroPortugal

Arbutus unedo L.(strawberry tree,Ericaceae)is a woody species with a circum-Mediterranean *** has considerable ecological relevance in southern European forests due to its resilience to abiotic and biotic *** edible red berries are used in the production of traditional products,including an expensive *** compounds extracted from the species have bioactive prop-erties used by the cosmetic and pharmaceutical *** strawberry tree has gone from a neglected species to become a highly valuable crop with large cultivated areas in southern European and North African *** to an increasing demand from farmers for plants with improved features,researchers have been trying to improve this spe-cies through conventional and biotechnological tools,focus-ing mainly on population analysis using molecular markers,in vitro cloning,tolerance to biotic and abiotic stresses,and intraspecific crosses to obtain genotypes with new *** objective of this review is to gather and update information about the species and make it available to researchers and *** research areas that are considered a priority for this species are highlighted.

关键词： Breeding Chemical profiling Ericaceae Microbiome Micropropagation

overcoming mitochondrial dysfunction in neurodegenerative diseases

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Neural Regeneration Research 2023年第7期18卷 1486-1488页

作者： joão Pessoa Ana I.Duarte CNC-Center for Neuroscience and Cell Biology CIBB-Center for Innovative Biomedicine and BiotechnologyUniversity of CoimbraCoimbraPortugal

Due to their intense electrical activity,neurons have high energy *** requirement makes them particularly sensitive to mitochondrial *** all eukaryotic cells,neurons have intrinsic mechanisms to mitigate the impact of mitochondrial dysfunction and its consequent production of toxic *** such(neuro)protective mechanisms,mitochondrial autophagy(mitophagy)is responsible for the removal of dysfunctional *** inhibition of mitophagy,together with insufficient mitochondrial activity,results in a shortage of adenosine triphosphate(ATP)and the accumulation of reactive oxygen species(RoS)(Simmons et al.,2020).

关键词： protective dysfunction intense

Magmatic Evolution of Garnet-Bearing highly Fractionated Granitic Rocks from Macao,Southeast China:Implications for Granite-Related Mineralization Processes

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journal of Earth Science 2021年第6期32卷 1454-1471页

作者： Pedro Quelhas joão Mata Ágata Alveirinho Dias Institute of Science and Environment University of Saint JosephRua de Londres106MacaoChina Instituto Dom Luiz Faculdade de CiênciasUniversidade de Lisboa1749-016LisboaPortugal

The widespread W-(mo)-Sn-Nb-Ta polymetallic mineralization in Southeast(SE)China is genetically associated with Mesozoic highly fractionated granitic *** rocks have enigmatic mineralogical and geochemical features,making its petrogenesis an intensely debated *** better understand the underlying magma evolution processes,petrography,garnet chemistry and whole-rock major and trace element data are reported for Jurassic highly fractionated granitic rocks and associated microgranite and aplitepegmatite dikes from Macao and compared with coeval similar granitic rocks from nearby areas in SE *** the fact that the most evolved rocks in Macao are garnet-bearing aplite-pegmatite dikes,the existence of coeval two-mica and garnet-bearing biotite and muscovite granites displaying more evolved compositions(e.g.,lower Zr/Hf ratios)indicates that the differentiation sequence reached higher degrees of fractionation at a regional *** crystal fractionation played an important role,late-stage fluid/melt interactions,involving F-rich fluids,imparted specific geochemical characteristics to Macao and SE China highly fractionated granitic rocks such as the non-CHARAC(CHArge-and-RAdius-Controlled)behavior of trace elements,leading,for example,to non-chondritic Zr/Hf ratios,Rare Earth Elements(REE)tetrad effects and Nb-Ta enrichment and *** process contributed to the late-stage crystallization of accessory phases only found in these highly evolved *** the latter,two populations of garnet were identified in MGI(Macao GroupⅠ)highly fractionated granitic rocks:small grossular-poor euhedral grains and large grossular-rich skeletal garnet grains with quartz *** first group was mainly formed through precipitation from highly evolved Mn-rich slightly peraluminous melts under low-pressure and relatively low temperature(~700℃)*** of upper crust metasedimentary materials may have contributed as a source of Mn and

关键词： highly fractionated granites aplite Macao(South China) Jurassic late-stage fluid/melt interactions garnet non-CHARAC REE tetrad effect

Impaired T-cell differentiation in diabetic foot ulceration

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Cellular & molecular Immunology 2017年第9期14卷 758-769页

作者： joão moura joão Rodrigues Marta Gonçalves Cláudia Amaral Margarida Lima Eugénia Carvalho Center for Neuroscience and Cell Biology(CNC) University of Coimbra3004-517 CoimbraPortugal Hospital de Santo Antonio(HSA) Centro Hospitalar do Porto(CHP)4099-001 PortoPortugal Unidade Multidisciplinar de Investigação Biomédica(UMIB/ICBAS/UP) PortoPortugal Department of Geriatrics University of Arkansas for Medical Sciences(UAMS)Little RockAR 72202USA Arkansas Children's Hospital Research Institute(ACHRI) Little RockAR 72202USA

Foot ulceration is one of the most debilitating complications associated with diabetes,but its cause remains poorly *** studies have been undertaken to understand healing kinetics or find possible therapies to enhance ***,few studies have been directed at understanding the immunological alterations that could influence wound healing in *** this study,we analysed the T-cell receptor(TCR)repertoire diversity in TCR-αβ^(+)T *** also analysed the distribution and phenotype of T cells obtained from the peripheral blood of healthy controls and diabetic individuals with or without foot *** results showed that diabetic individuals,especially those with foot ulcers,have a significantly lower naive T-cell number and a poorer TCR-Vβrepertoire *** also showed that the reduced TCR-Vβrepertoire diversity in diabetic individuals was mainly owing to the accumulation of effector T cells,the major source of tumour necrosis factor-αproduction,which was even more pronounced in patients with acute foot ***,the expression of several inflammatory chemokine receptors was significantly reduced in diabetic *** conclusion,effector T-cell accumulation and TCR repertoire diversity reduction appear to precede the development of foot *** finding may open new immunological therapeutic possibilities and provide a new prognostic tool in diabetic wound care.

关键词： diabetes T-cells T-cell repertoire diversity wound healing