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Body size structure of Pleistocene mammalian communities: what support is there for the “island rule”?

Integrative Zoology 2009年第4期4卷 341-356页

作者： maria R.PALOMBO Department of Earth Sciences University of Rome“La Sapienza”RomeItaly

Islands are often regarded by scientists as living laboratories of evolution and an optimal context for the study of forces influencing evolution and *** main issues have been attentively scrutinized and debated:the loss of biodiversity and the peculiar changes undergone by island settlers,primarily changes in size of endemic *** time,several hypotheses have been formulated to explain the causal mechanism of body size *** of those islands where mainland taxa migrate more than once provide the most interesting data to answer the question of whether or not trends of insular taxa result from a predictable response to differences in competition and availability of niches between insular and mainland *** contribute to the debate,the body size structure of the Pleistocene mammalian faunas from two Mediterranean islands,Sicily and Crete,were analyzed and compared with the structure of coeval mainland *** results obtained suggest that:(i)size of endemic species does not directly depend on the area of islands;(ii)evolution and size of endemic species seems somewhat affected by the degree of isolation(constraining coloniza-tion from mainland)and physiography(sometimes permitting adaptive radiation);(iii)in unbalanced insular communities,the shift in size of non-carnivorous species largely depends on the nature of competing species;and(iv)body size of carnivorous species mainly depends on the size of the most available ***,it is rational to suppose that the body size of insular mammals mainly results from the peculiar biological dynamics that characterizes unbalanced insular *** interaction,particularly the intraguild competition,is the major driver behind the evolution of insular communities,leading towards an optimization of energy balance through a change in body size of endemic settlers.

关键词： body size islands mammals Mediterranean Pleistocene.Body size structure of Sicilian and Cretan Pleistocene fauna

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Past climate and vegetation in Southeast Bulgaria——a study based on the late Miocene pollen record from the Tundzha Basin

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Journal of Palaeogeography 2019年第1期8卷 43-67页

作者： Dimiter Ivanov maria Lazarova Institute of Biodiversity and Ecosystem Research Bulgarian Academy of Sciences

The results of palynological studies on the late Miocene freshwater deposits of the Tundzha Basin(Southeast Bulgaria, SE Europe) are presented. The basin is relatively well known in terms of geology and *** age of sediments in the Tundzha Basin ranges between the late Miocene to the Pliocene, based on mammal and diatom fossils. We carried out a palynological analysis of clayey sediments interlayered with coal beds from four cores and from one outcrop, aiming to obtain information about the composition and the structure of fossil vegetation. The ratios between the main floristic elements and the composition of the fossil flora are analysed and discussed from a palaeoecological point of view. Several main vegetation palaeocommunities were recorded:swamp forests, mixed mesophytic, communities of aquatic plants, and herbaceous palaeocoenoses. The changes in vegetation and in plant diversity are identified. The palaeoclimate analysis indicates a warm temperature climate with high rainfall and mild winter temperatures, without seasonal drier conditions. The early Pontian climate was about 3–4 ℃ warmer than today, with rainfalls per year at least 300 mm higher than today. The results of palaeoecological analysis of the flora and of the quantitative palaeoclimate data show that the climate in the Southeast Bulgaria indicates a climate change towards slight cooling and some drying. This event is consistent with the period of accumulation of the upper, undivided part of the Elhovo Formation.

关键词： Palynology Palaeobotany Coexistence approach Neogene Tundzha Basin Bulgaria

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An illustrated checklist of macrofaunal molluscs from soft-sediments of the Abrolhos Parcel(northeastern,Brazil)with 15 new records

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Journal of Oceanology and Limnology 2021年第2期39卷 671-682页

作者： Flávia maria Pereira da COSTA Ana maria Setubal PIRES-VANIN Departamento de Oceanografi a Biológica Instituto Oceanográfi coUniversidade de São PauloSão Paulo 05508-120Brazil

Comprehensive understanding of marine biodiversity is essential for conservation,especially for vulnerable *** this paper,we implemented and illustrated a checklist of molluscs from the Abrolhos Parcel,Brazil,the most important coralline area in South Atlantic *** list features 100 species belonging to 4 classes and 85 genera,of which 15 are new records for Bahia State,northeast *** results highlight the potential for new records in the *** species came from 54 unconsolidated sediment samples collected from the bottom of the reef with a 0.042-m^(2) van Veen *** the listed species,Curveulima sp.,Notarchus *** Guyanella clenchi are new records for the South Atlantic,while Caecum metamorphosicum,Eratoidea janeiroensis,Volvarina serrei,Solemya notialis,Solariorbis shimeri,and Amphithalamus glabrus are endemic to Brazilian waters.A comparison of our results with those obtained in other reef environments indicates that the Abrolhos Parcel has a rich malacofauna and suggests that many more species can still be found with more samplings.

关键词： Bivalvia Gastropoda micromolluscs Scaphopoda Solenogastres southwest Atlantic

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Degenerate Nonlinear Elliptic Equations Lacking in Compactness

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Chinese Annals of Mathematics,Series B 2016年第1期37卷 53-72页

作者： maria MALIN Cristian UDREA Department of Mathematics University of Craiova

In this paper, the authors prove the existence of solutions for degenerate elliptic equations of the form-div(a(x)▽_p u(x)) = g(λ, x, |u|^(p-2)u) in R^N, where ▽_pu =|▽u|^(p-2)▽u and a(x) is a degenerate nonnegative weight. The authors also investigate a related nonlinear eigenvalue problem obtaining an existence result which contains information about the location and multiplicity of eigensolutions. The proofs of the main results are obtained by using the critical point theory in Sobolev weighted spaces combined with a Caffarelli-Kohn-Nirenberg-type inequality and by using a specific minimax method, but without making use of the Palais-Smale condition.

关键词： Degenerate equations p-Laplacian Sobolev weighted spaces Mountain-pass theorem

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Biochronology,paleobiogeography and faunal turnover in western Mediterranean Cenozoic mammals

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Integrative Zoology 2009年第4期4卷 367-386页

作者： maria R.PALOMBO Department of Earth Sciences University of Rome“La Sapienza”RomeItaly

Cenozoic terrestrial mammals from Sardinia contribute substantial information for reconstructing the complex his-tory of the western *** occurrence of endemic perissodactyls in Eocene marine and marsh deposits suggests the existence of ecological or physical barriers between the Corso-Sardinian massif and the Iberian-Occitanic *** the end of the Oligocene,isolation of Sardinia was almost complete,although a migration from Europe occurred at the beginning of the Early Miocene,as indicated by the unbalanced endemic fauna from *** the Late Miocene,the Tusco-Sardinian palaeobioprovince came into existence as an isolated region inhab-ited by the quite diversified,but notably endemic,Oreopithecus *** was definitely isolated from Tuscany by the Messinian,but temporary connections with the European mainland possibly allowed the colonization of forerunners of some Sardinian Pliocene *** the Plio-Pleistocene,Sardinia maintained permanent ***,sea level drop,resulting in a relatively short distance between Sardinia and the European mainland,allowed different migratory *** the Late Pliocene to the Late Pleistocene–Holocene,two main mammalian faunal complexes(FC)can be recognized:the Nesogoral FC(Late Pliocene-Early Pleistocene)and the Microtus(Tyrrhenicola)FC(late Early Pleistocene–Early Holocene).At the transition from Nesogoral to Microtus(Tyrrhenicola)FC,approximately 47%of the genera and 76%of the species disappeared,while approximately 58%of the genera and 71%of the species appeared.A noticeable turnover followed the arrival of Neolithic man and his accompanying ***,Praemegaceros was still present at about 7000 years BP,while Microtus(Tyrrhenicola)and Prolagus are respectively recorded in the Bronze and Iron Ages.

关键词： biochronology Cenozoic faunal turnovers mammals Sardinia

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Neuroprotection and antioxidants

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Neural Regeneration Research 2016年第6期11卷 865-874页

作者： maria Lalkovicová Viera Danielisová Institute of Neurobiology Slovak Academy of Sciences

Ischemia as a serious neurodegenerative disorder causes together with reperfusion injury many changes in nervous tissue. Most of the neuronal damage is caused by complex of biochemical reactions and substantial processes, such as protein agregation, reactions of free radicals, insufficient blood supply, glutamate excitotoxicity, and oxidative stress. The result of these processes can be apoptotic or necrotic cell death and it can lead to an irreversible damage. Therefore, neuroprotection and prevention of the neurodegeneration are highly important topics to study. There are several approaches to prevent the ischemic damage. Use of many modern therapeutical methods and the incorporation of several substances into the diet of patients is possible to stimulate the endogenous protective mechanisms and improve the life quality.

关键词： neuroprotection ischemia oxidative stress antioxidants cerebral damage nutrition vitamins omega-3 fatty acids flavonoids polyphenols statins

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Trait allometries generate super-honesty in Anolis dewlaps and may underlie sexual dimorphism

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Integrative Zoology 2017年第2期12卷 97-111页

作者： maria PETELO Lindsey SWIERK Department of Biology University of Hawaiʻi at MānoaHonoluluUSA Las Cruces Biological Station Organization for Tropical StudiesSan VitoCoto BrusCosta Rica School of Forestry and Environmental Studies Yale UniversityNew HavenConnecticutUSA

Whether or not sexually selected traits consistently exhibit positive allometry(*** disproportionately large in larger individuals)is an ongoing *** models and exceptions to this rule suggest that the underlying drivers of sexual trait allometry are ***,we compare allometries of sexual and non-sexual traits of a species(Anolis aquaticus)within a well-studied lizard genus to test the competing hypotheses that sexual traits are,or are not,defined by positive *** further consider the relationships of trait functions,which are relatively well understood in the genus Anolis,and allometry to identify potential drivers of allometric *** particular,we explore how trait allometries interact to influence total organism function and generate sexual *** quantified size(of targeted traits)and color of a sexual signal(the dewlap)in Anolis aquaticus in the *** dewlap conveyed information relevant to intra-sexual combat and exhibited positive ***,our results suggest that using single-trait allometries as indicators of past selection provides only an incomplete understanding of trait *** the function of positive allometry in some individual sexual signals(*** conveying“super-honest”information)may be straightforward,we illustrate how scaling relationships interact synergistically to influence the function of phenotypes and propose avenues for future research.

关键词： Anolis[Norops]aquaticus color morphology reproductive strategy scaling

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Mitochondria in Huntington’s disease:implications in pathogenesis and mitochondrial-targeted therapeutic strategies

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Neural Regeneration Research 2023年第7期18卷 1472-1477页

作者： Anamaria Jurcau Carolina maria Jurcau Department of Psycho-Neurosciences and Rehabilitation Faculty of Medicine and PharmacyUniversity of OradeaOradeaRomania Neurology 3 Ward Clinical Emergency Hospital OradeaRomania Faculty of Medicine and Pharmacy University of OradeaRomania

Huntington’s disease is a genetic disease caused by expanded CAG repeats on exon 1 of the huntingtin gene located on chromosome *** evidence implicates impaired mitochondrial energetics,altered mitochondrial biogenesis and quality control,disturbed mitochondrial trafficking,oxidative stress and mitochondrial calcium dyshomeostasis in the pathogenesis of the ***,conventional mitochondrial-targeted molecules,such as cysteamine,creatine,coenzyme Q10,or triheptanoin,yielded negative or inconclusive ***,future therapeutic strategies,aiming to restore mitochondrial biogenesis,improving the fission/fusion balance,and improving mitochondrial trafficking,could prove useful tools in improving the phenotype of Huntington’s disease and,used in combination with genome-editing methods,could lead to a cure for the disease.

关键词： antioxidants calcium homeostasis Huntington’s disease mitochondrial biogenesis mitochondrial fission/fusion mitochondrial trafficking oxidative phosphorylation oxidative stress SS peptides therapeutic intervention

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Structure and heat capacity of the NaCeF_4 compound

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Journal of Rare Earths 2013年第9期31卷 911-915页

作者： Virgil Constantin Ana-maria Popescu "Ilie Murgulescu" Institute of Physical Chemistry of the Romanian Academy Splaiul Independentei 202 st.060021BucharestRomania

This work continued our general research program on obtaining metallic cerium by electrodeposition from NaCeF4 dis-solved in different molten fluorides. The structure of NaCeF4 （cubic or hexagonal depending on the way of preparation） was estab-lished by DTA analysis, IR spectra and X-ray diffraction. The heat capacity （Cp） of NaCeF4 was measured by differential scanning calorimetry in the temperature range of 300-1093 K using the“step-method”. The Cp was fitted by an equation with a satisfactory re-sult. Heat capacity was compared with that calculated from the Neumann-Kopp rule （NKR） and the deviations observed were consis-tent with the stability of the NaCeF4 compound.

关键词： cerium compounds structure heat capacity NaCeF4 rare earths

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Transformation of PGM in supra subduction zones: Geochemical and mineralogical constraints from the Veria (Greece) podiform chromitites

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Geoscience Frontiers 2021年第2期12卷 827-842页

作者： George Tsoupas maria Economou-Eliopoulos Department of Economic Geology Geochemistry Faculty of Geology and GeoenvironmentNational and Kapodistrian University of AthensPetropolisGR-15784AthensGreece

Extremely abundant PGE-minerals(PGM)hosted in chromitites from the Veria ophiolite complex in Macedonia(***)may be unique among ophiolite *** study focuses on differences between the low-and high-PGE *** textural,mineralogical and geochemical constraints from those ores are presented,aiming to define factors controlling the PGE enrichment in a supra subduction environment,in the light of postmagmatic *** whole ore analyses for mmajor and trace elements indicated an unusually high-IPGE content(up to 25 ppm)and higher Fe,Ca,Mn,Zn and V contents in high-PGE compared to low-PGE in massive *** wide compositional variation of chromite,even in the same polished section,the occurrence of very fine PGM(less than 20μm)as inclusions within chromite and extremely large(>1000μm),angular or fine-grained PGM aggregates ones within a matrix of highly fragmented chromite-Cr-garnet matrix,may indicate crystallization/recrystallization of chromite from more than one precursor ***(RuS2)is very limited,occurring as remnants surrounding by Ru–Os–Ir oxides/hydroxides,of a wide compositional *** occurs as euhedral crystals up to 200μm,surrounding by chromite,as anhedral exsolutions 1–200μm within laurite,or creating segregates with platarsite and relics of(Ru,Pt,Rh,Os)***–Ru–Rh–Pd-minerals occur commonly as relatively fine-grained assemblages,up to 50μm,along with irarsite and other relics of(Ru,Pt,Rh,Os)***-alloys show a variation ranging from tetraferroplatinum to Pt–Ir–Fe–Ni *** presence of laurite relics in large IPGM,awaruite,heazlewoodite,and carbon-bearing material reflecting a super-reducing environment,and the transformation of primary PGM into Os–Ir–Ru-alloys and oxides/hydroxides in association with Fe-chromite and Fe3t-bearing garnet(andradite-uvarovite solidsolution series)may reflect changes of the redox conditions from reducing to *** relatively high N

关键词： Platinum-group minerals Chromite Inclusions P-T-conditions Veria

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