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Like father,like son?Similarity of syllable repertoires and structures in the songs of first-year male Tree Pipits and their potential tutors 认领 引用
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作者 Hana Kahounová Niall H.K.Burton +1 位作者 Adam Petrusek Tereza Petrusková 《Avian Research》 SCIE CAS CSCD 2026年第3期668-681,共14页
Birdsong in oscine passerines is socially learned,but the relative influence of different tutors in the wild remains unclear for many species.We examined song acquisition in the Tree Pipit(Anthus trivialis:Motacillida... Birdsong in oscine passerines is socially learned,but the relative influence of different tutors in the wild remains unclear for many species.We examined song acquisition in the Tree Pipit(Anthus trivialis:Motacillidae),a migratory passerine with critical-period learning and temporally stable,individually unique syllable repertoires.Through a long-term monitoring study(2016–2025)in eastern England,we analyzed the repertoires of 413 males,including 22 ringed as nestlings and recorded later as adults.For most of these focal males,we identified three potential tutor groups:social fathers(territorial males affiliated to the focal males'nests),natal nest neighbours,and territory neighbours in the first breeding season.Repertoires of studied males were described by the presence/absence of visually classified syllable types,and structural similarity of the two most variable syllable categories was quantified using dynamic time warping.Assessment of the similarity of syllable repertoires suggested that male Tree Pipits learn from multiple local males rather than selecting one specific tutor or preferred tutor group.Repertoire composition and structural similarity of one syllable category(but not the other)indicated higher similarity of focal males'vocalization to those of natal nest neighbours than to those of randomly selected locally co-occurring males;this pattern,however,was driven only by a subset of focal males.Sons'songs were never very similar to those of their social fathers,and siblings from the same nests always developed dissimilar repertoires.Structural similarity in one complex syllable category did not predict similarity in the other,also indicating that syllables tend to be learnt from different tutors.When assembling their repertoires,young male Tree Pipits develop individually unique characteristics while reflecting local acoustic traditions.Combined with strong site fidelity of both young birds and adults,learning from various local sources likely contributes to fine-scale geographic variation in the studied species'song,detectable even within the studied region between areas separated by ca.10 km. 展开更多
关键词 Anthus trivialis Birdsong learning Dynamic time warping Geographic song variation Individual acoustic monitoring Repertoire similarity
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Land use/land cover changes after the decline of mountain chalet farming in the Krkono?e and Hruby Jeseník Mountains, Czechia, since the mid-20th century 认领 引用
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作者 HEJDA Tomás KUPKOVA Lucie BOUDNY Zdeněk 《Journal of Mountain Science》 SCIE CSCD 2025年第4期1119-1150,共32页
Chalet farming,as a specific type of agricultural landscape management,has been established in many European mountain ranges,including the Krkono?e Mountains and the Hruby Jeseník Mountains in Czechia.During the ... Chalet farming,as a specific type of agricultural landscape management,has been established in many European mountain ranges,including the Krkono?e Mountains and the Hruby Jeseník Mountains in Czechia.During the operation of such farming from 16/17th century till 1945,many changes in land use/land cover and landscape at all occurred,which are generally evaluated positively.Turbulent events including political,economic and social changes and the displacement of the German-speaking population associated with them in the mid-20th century rapidly ended this development,causing significant landscape changes,such as the abandonment of agricultural land and succession,afforestation,expansion of the alpine tree line,reduction of diversity.The aim of our study is to evaluate changes of land cover(forests,dwarf pine,grasslands,other areas)from 1936/1946 till 2021,secondary succession and driving forces of change for selected meadow enclaves in the Krkonose Mountains and the Hruby Jeseník Mountains after the decline of mountain chalet farming since the middle of 20th century.We used remote sensing methods(aerial imagery)and field research(dendrochronology and comparative photography)to detect the land use/land cover changes in the selected study areas in the Krkono?e Mountains and the Hruby Jeseník Mountains.We documented the process of the succession,which occurred almost immediately after the end of farming,peaking about 10–20 years later,with an earlier start in the Hruby Jeseník Mountains.The succession led to the significant change of land use/land cover and these processes were similar in both mountain ranges.The largest changes were a decrease in grasslands by 62%–64%and an increase in forest area by 33%–40%for both study areas.The abandonment of land is the main consequence of a crucial political driving forces(displacement of German-speaking population)in the Krkono?e Mountains and the Hruby Jeseník Mountains. 展开更多
关键词 Chalet farming Land use/land cover change Alpine treeline Succession Krkonoše Mountains HrubýJeseník Mountains
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Rime ice formation:Insight into time trends over the last two decades based on observations in a Central European country 认领 引用
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作者 Iva HŮNOVÁ Marek BRABEC +2 位作者 Marek MALÝ Anna VALERIÁNOVÁ Libor ELLEDER 《Journal of Mountain Science》 SCIE CSCD 2026年第2期470-488,共19页
Rime ice is an effective winter ambient air pollution accumulator.Due to its higher ion content as compared to snow it is a non-negligible contributor to atmospheric deposition fluxes with potential environmental cons... Rime ice is an effective winter ambient air pollution accumulator.Due to its higher ion content as compared to snow it is a non-negligible contributor to atmospheric deposition fluxes with potential environmental consequences,particularly in mountain regions.Here we explore spatio-temporal patterns of rime formation as a proxy for the propensity of individual sites to form rime ice.We present the recent time trends in rime ice occurrence and thickness measured by 23 professional meteorological stations in the Czech Republic in 2002–2023.In an exploratory data analysis,we found high year-to-year variability in rime occurrence and thickness at all sites.According to the annual mean number of hours with rime detected,the stations situated at the highest altitudes are significantly different(higher)from the rest of the sites.The highest rime hour and thickness records by far were observed at the LYSA station in the Beskydy(Beskid)Mts situated at the exposed mountaintop and highly elevated above the surrounding terrain.For advanced statistical modelling of rime thickness,we used two generalised additive models that account for long-term trends(potentially nonlinear),seasonal and daily variability.In an expanded model we further considered the effect of the North Atlantic Oscillation(NAO)index.All the parameters included in the models proved to be statistically significant,although the strength of their effect differed.Factors affecting the rime formation(meteorology and terrain)are strongly site-specific and identification of the significance of individual influencing factors remains a challenging task for our future research.Here,we explore a rare long-term rime record with detailed temporal resolution from multiple uniformly measured sites,which significantly enhances our understanding of rime formation.Additionally,the rime record is from a temperate zone,where rime forms only during a small part of the year. 展开更多
关键词 Long term rime trends Seasonal variability Censored data Generalised additive model Czech Republic
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Ultrahigh Lattice Thermal Conductivity in 2D Magnetic VSi2N4 Driven by Exceptional Stiffness 认领 引用
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作者 Zhunyun Tang Xiaoxia Wang +6 位作者 Shaogang Peng Tao Ouyang Jin Li Chaoyu He Mingxing Chen Junjie He Chao Tang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2026年第6期140-140,141-146,I0132-I0137,共1页
Two-dimensional(2D)magnetic semiconductors are promising candidates for next-generation spintronic,memory,and logic devices.However,their practical deployment is often hindered by poor heat dissipation due to the low ... Two-dimensional(2D)magnetic semiconductors are promising candidates for next-generation spintronic,memory,and logic devices.However,their practical deployment is often hindered by poor heat dissipation due to the low lattice thermal conductivity(κL).Herein,we identify a 2D ferromagnetic semiconductor,VSi2N4,that exhibits an ultrahighκL.Using first-principles calculations combined with the MACE machine learning potential and the phonon Boltzmann transport equation,we reveal that the room-temperatureκL of VSi2N4 is about 317 W m−1 K−1.This value is one order of magnitude higher than that of most known 2D magnets and represents the highestκL reported in these materials.This superior thermal transport mainly originates from the large phonon group velocity and weak phonon-phonon scattering.Notably,even with the inclusion of four-phonon scattering,theκL reduction is merely approximately 8.3%,indicating limited high-order anharmonicity.Meanwhile,our analysis further reveals that theκL value of VSi2N4 significantly deviates from the conventional scaling trends established by Slack based on the number of atoms per unit cell and the average atomic mass.Nevertheless,a clear positive correlation is established with the Young’s modulus,underscoring mechanical stiffness as an effective descriptor for superior thermal transport in 2D systems.The exceptional stiffness of VSi2N4 is attributed to the strong bonding resulting from the highly localized charge distribution between the Si and N atoms.These findings presented in this work not only reveal VSi2N4 as a unique platform integrating robust ferromagnetism with outstanding heat dissipation,but also provide crucial guidance for the thermal manage-ment of future high-performance 2D magnetic materials. 展开更多
关键词 phonon group velocity VSi N mace machine learning potential d ferromagnetic semiconductorvsi n phonon boltzmann transport equationwe low lattice thermal conductivity l hereinwe heat dissipation D magnetic semiconductors
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Epigenetic and non-epigenetic mode of SIRT1 action during oocyte meiosis progression 认领 引用 被引量：5
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作者 Jan Nevoral Lukas Landsmann +11 位作者 Miriam Stiavnicka Petr Hosek Jiri Moravec Sarka Prokesova Hedvika Rimnacova Eliska Koutna Pavel Klein Kristyna Hoskova Tereza Zalmanova Tereza Fenclova Jaroslav Petr Milena Kralickova 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第4期895-906,共12页
Background: SIRT1 histone deacetylase acts on many epigenetic and non-epigenetic targets. It is thought that SIRT1 is involved in oocyte maturation;therefore, the importance of the ooplasmic SIRT1 pool for the further... Background: SIRT1 histone deacetylase acts on many epigenetic and non-epigenetic targets. It is thought that SIRT1 is involved in oocyte maturation;therefore, the importance of the ooplasmic SIRT1 pool for the further fate of mature oocytes has been strongly suggested. We hypothesised that SIRT1 plays the role of a signalling molecule in mature oocytes through selected epigenetic and non-epigenetic regulation.Results: We observed SIRT1 re-localisation in mature oocytes and its association with spindle microtubules.In mature oocytes, SIRT1 distribution shows a spindle-like pattern, and spindle-specific SIRT1 action decreasesα-tubulin acetylation. Based on the observation of the histone code in immature and mature oocytes, we suggest that SIRT1 is mostly predestined for an epigenetic mode of action in the germinal vesicles(GVs) of immature oocytes. Accordingly, BML-278-driven trimethylation of lysine K9 in histone H3 in mature oocytes is considered to be a result of GV epigenetic transformation.Conclusions: Taken together, our observations point out the dual spatiotemporal SIRT1 action in oocytes,which can be readily switched from the epigenetic to non-epigenetic mode of action depending on the progress of meiosis. 展开更多
关键词 Epigenetics Histone code In vitro maturation Oocyte SIRT1 Sirtuin 1
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Distribution Patterns of Medicinal Plants along an Elevational Gradient in Central Himalaya,Nepal 认领 引用 被引量：4
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作者 Maan B.ROKAYA Zuzana MÜNZBERGOVÁ +1 位作者 Mani R.SHRESTHA Binu TIMSINA 《Journal of Mountain Science》 SCIE CSCD 2012年第2期201-213,共13页
This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions,and between medicinal plants and all vascular plants.We used the pu... This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions,and between medicinal plants and all vascular plants.We used the published sources for elevation records of 2,331 medicinal plant species to interpolate presence between minimum and maximum elevations and estimated medicinal plant richness for each 100-m elevational band. Monte Carlo simulations were used to test whether differences in elevational distribution between different groups of medicinal plants were significant. Total number of medicinal plants as well as different groups showed unimodal relationship with elevation. The elevational distributions of medicinal plants significantly differ between regions and between medicinal plant groups.When comparing the richness of all medicinal plants to all vascular plants,Monte Carlo simulations indicated that the numbers of medicinal plants are higher than expected at low elevations.The highest richness of medicinal plants at low elevation could be possibly due to favorable environmental factors such as high temperature, rainfall,sunlight or due to higher density of human population and thus higher pressure on use of any plants in lower elevations. 展开更多
关键词 Species richness Rapoport＇s elevational rule Mid-domain effect Randomization test Unimodal pattern Himalaya Nepal
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The ghost of past climate acting on present-day plant diversity:Lessons from a climate-based delimitation of the tropical alpine ecosystem 认领 引用 被引量：2
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作者 Martha Kandziora Juan M.Gorospe +5 位作者 Luciana Salomon Diana L.A.Vasquez Maria Pinilla Vargas Filip Kolar Petr Sklenar Roswitha Schmickl 《Journal of Systematics and Evolution》 SCIE CAS CSCD 2024年第2期275-290,共16页
Habitat stability is important for maintaining biodiversity by preventing species extinction,but this stability is being challenged by climate change.The tropical alpine ecosystem is currently one of the ecosystems mo... Habitat stability is important for maintaining biodiversity by preventing species extinction,but this stability is being challenged by climate change.The tropical alpine ecosystem is currently one of the ecosystems most threatened by global warming,and the flora close to the permanent snow line is at high risk of extinction.The tropical alpine ecosystem,found in South and Central America,Malesia and Papuasia,Africa,and Hawaii,is of relatively young evolutionary age,and it has been exposed to changing climates since its origin,particularly during the Pleistocene.Estimating habitat loss and gain between the Last Glacial Maximum(LGM)and the present allows us to relate current biodiversity to past changes in climate and habitat stability.In order to do so,(i)we developed a unifying climate-based delimitation of tropical alpine regions across continents,and(ii)we used this delimitation to assess the degree of habitat stability,that is,the overlap of suitable areas between the LGM and the present,in different tropical alpine regions.Finally,we discuss the link between habitat stability and tropical alpine plant diversity.Our climate-based delimitation approach can be easily applied to other ecosystems using our developed code,facilitating macro-comparative studies of habitat dynamics through time. 展开更多
关键词 extinction risk habitat dynamics Last Glacial Maximum plant diversity refugia tropical alpine
Molecular bases for parallel evolution of translucent bracts in an alpine "glasshouse" plant Rheum alexandrae (Polygonaceae) 认领 引用 被引量：2
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作者 Bing-Bing LIU Lars OPGENOORTH +5 位作者 Georg MIEHE Dong-Yuan ZHANG Dong-Shi WAN Chang-Ming ZHAO Dong-Rui JIA Jian-Quan LIU 《Journal of Systematics and Evolution》 SCIE CAS CSCD 2013年第2期134-141,共8页
Parallel evolution provides an excellent framework to infer the genetic bases of adaptive traits and understand the importance of natural selection in shaping current biodiversity. The upper leaves of the ＂glasshouse... Parallel evolution provides an excellent framework to infer the genetic bases of adaptive traits and understand the importance of natural selection in shaping current biodiversity. The upper leaves of the ＂glasshouse plants＂ transform into translucent bracts that show numerous adaptions in alpine habitats. It remains unknown whether similar molecular changes occur under the parallel bract evolution of different ＂glasshouse＂ species. In this study, we compared the results on phenotypic and physiological differences and presented the results of cDNA- AFLP analyses of transcriptional changes between translucent bracts and normal leaves in Rheum alexandrae. We also examined the homologous candidate genes with the same expression changes between this species and another ＂glasshouse＂ species, R. nobile. We found that bracts of R. alexandrae are similar to those of R. nobile in anatomical features： chloroplasts have degenerated and chlorophyll contents are greatly reduced, which suggests that foliar photosynthetic functions in bracts of both species have been reduced or totally altered. Among the 6000 transcript-derived fragments （TDFs） in bracts and leaves of R. alexandrae, 420 （7%） were differentially expressed （up- or downregulated） between bracts and normal leaves. There were a total of 13 homologous TDFs with the same expression changes between R. alexandrae and the previously studied R. nobile. Except for the two that were not functionally annotated, eight of the homologous TDFs were found to be involved in stress and defense responses whereas the other three were related to photosynthesis. The up- or downregulation of these candidate genes was highly congruent with anatomical characteristics and adaptive functions of the bracts found for ＂glasshouse＂ plants. These findings suggested that the ＂glasshouse＂ phenotypes may have common molecular bases underlying their parallel evolution of similar adaptive functions and highlighted the importance of the natural selection in producing such phenotypes. 展开更多
关键词 cDNA-AFLPs ＂glasshouse＂ plants parallel evolution Rheum alexandrae.
Spontaneous emergence of overgrown molar teeth in a colony of Prairie voles(Microtus ochrogaster) 认领 引用
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作者 Andrew H Jheon Michaela Prochazkova +4 位作者 Michael Sherman Devanand S Manoli Nirao M Shah Lawrence Carbone Ophir Klein 《International Journal of Oral Science》 SCIE CAS CSCD 2015年第1期23-26,共4页
Continuously growing incisors are common to all rodents, which include the Microtus genus of voles. However, unlike many rodents, voles also possess continuously growing molars. Here, we report spontaneous molar defec... Continuously growing incisors are common to all rodents, which include the Microtus genus of voles. However, unlike many rodents, voles also possess continuously growing molars. Here, we report spontaneous molar defects in a population of Prairie voles （Microtus ochrogaster）. We identified bilateral protuberances on the ventral surface of the mandible in several voles in our colony. In some cases, the protuberances broke through the cortical bone. The mandibular molars became exposed and infected, and the maxillary molars entered the cranial vault. Visualisation upon soft tissue removal and microcomputed tomography （microCT） analyses confirmed that the protuberances were caused by the overgrowth of the apical ends of the molar teeth. We speculate that the unrestricted growth of the molars was due to the misregulation of the molar dental stem cell niche. Further study of this molar phenotype may yield additional insight into stem cell regulation and the evolution and development of continuously growing teeth. 展开更多
关键词 continuously growing teeth molar phenotype mutation stem cell regulation voles
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Preliminary study on investigation of zoonotic visceral leishmaniasis in endemic foci of Ethiopia by detecting Leishmania infections in rodents 认领 引用
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作者 Wossenseged Lemma Asrat Bizuneh +8 位作者 Habte Tekie Habtamu Belay Hirut Wondimu Aysheshm Kassahun Welelta Shiferaw Meshesha Balkew Ibrahim Abassi Gad Baneth Asrat Hailu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第4期396-400,共5页
Objective:To investigate the zoonotic visceral leishmaniasis(ZVL) by identification of the most probable reservoir hosts using parasite isolation and analysis of a possible transmission dynamics of the disease in extr... Objective:To investigate the zoonotic visceral leishmaniasis(ZVL) by identification of the most probable reservoir hosts using parasite isolation and analysis of a possible transmission dynamics of the disease in extra-domestic agricultural fields and rural villages.Methods:Rodents were collected from selected study sites in kala-azar endemic areas based on information for localities of kala-azar cases for screening of Leshmania infections using parasitological,serological and polymerase chain reaction(PCR) from March.2013 to January,2014.Ketamine(Clorketam Veterinary) was used to anaesthesize the rodents according the prescribed dosage(average 2 mg/kg for intra-venous route).The blood obtained using sterile needle was dropped into sterile filter paper and allowed to air dry before sealing in plastic bags.The tissues from liver,spleen and skin were macerated in Locke's solution before transferring them into NNN medium.Blood and touch smears of liver,spleen,skin and bone marrow were prepared for fixing using methanol and staining by Giemsa stain for microscopy.These tissues were also ascd for DNA extractions and PCR amplification of Leishmania infection.Results:A total of 335 rodents(13 species) were analyzed by sampling internal organs.The infection rate by PCR was 11.1%(6/54) for Arvicanthis nilothicas compared to 17.6%(3/17) and 12.5%(2/16) for Acomys cahirinus and Tarera(C) robustus respectively.Almost all the infections were found from bone marrow samples(8/48 or 16.7%) compared with 1/91(1.1%) liver,2/87(2.2%) spleen and 0/87(0%) skin.In all study sites with past human VL cases,rodents and proved vectors shared similar habitats.Conclusions:Leishmania donovani might circulate among different species of rodents in kala-azar endemic lowlands and valleys of Ethiopia by Phlebotamus orientalis and Phlebotomus martini.Detailed studies to substantiate the preliminary data on the possible role of these rodents arc urgently needed. 展开更多
关键词 Zoonotic visceral leishmaniasis Phlebotomus orientalis Phlebotomus martini Leishmania donovani Reservoir hosts Ethiopia
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Glacier retreat, rock weathering and the growth of lichensin the Churup Valley, Peruvian Tropical Andes 认领 引用
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作者 Adam EMMER Anna JURICOVA Bijeesh Kozhikkodan VEETTIL 《Journal of Mountain Science》 SCIE CSCD 2019年第7期1485-1499,共15页
The most heavily glacierized tropical range in the world– the Peruvian Cordillera Blanca-has been losing ice since the end of the Little Ice Age(LIA).In this study,the decline of the Churup glacier(9°28’18"... The most heavily glacierized tropical range in the world– the Peruvian Cordillera Blanca-has been losing ice since the end of the Little Ice Age(LIA).In this study,the decline of the Churup glacier(9°28’18"S;77°25’02"W)and associated processes were documented employing multi-proxy approach including the analysis of remotely sensed images(1948-2016),the Schmidt hammer rock test and lichenometric dating.It is shown that Churup glacier has lost the vast majority of its estimated LIA extent(1.05±0.1 km^2;45.0×10^6-57.4×10^6 m^3).The rate of glacier retreat is documented to vary in space(SE,SW and NW-facing slopes)and time,with the peak between 1986 and 1995.With an area of 0.045 km^2 in 2016,it is expected that the complete deglaciation of the Churup valley is inevitable in the near future.Recently(post-LIA)exposed bedrock surfaces have shown higher R-values(54.2-66.4,AVG 63.3,STDEV 2.9)compared to pre-LIA exposed surfaces(46.1-59.3,AVG 50.1,STDEV 4.9),confirming the links to the duration of rock weathering.The Lichenometric dating is applied to recently exposed areas and elevations above 4800 m a.s.l.,revealing only limited reliability and agreement with the age of deglaciation estimated from remotely-sensed images in such an environment. 展开更多
关键词 Cordillera Blanca Tropical glaciers Deglaciation Geoenvironmental change Lichenometry Rhizocarpon geographicum Schmidt hammer Andes
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Distinct gut microbiota profiles in patients with primary sclerosing cholangitis and ulcerative colitis 认领 引用 被引量：51
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作者 Lukas Bajer Miloslav Kverka +7 位作者 Martin Kostovcik Peter Macinga Jiri Dvorak Zuzana Stehlikova Jan Brezina Pavel Wohl Julius Spicak Pavel Drastich 《World Journal of Gastroenterology》 SCIE CAS 2017年第25期4548-4558,共11页
To characterize the gut bacterial microbiota of patients with primary sclerosing cholangitis(PSC)and ulcerative colitis(UC).METHODSStool samples were collected and relevant clinical data obtained from 106 study partic... To characterize the gut bacterial microbiota of patients with primary sclerosing cholangitis(PSC)and ulcerative colitis(UC).METHODSStool samples were collected and relevant clinical data obtained from 106 study participants,43 PSC patients with(n=32)or without(n=11)concomitant inflammatory bowel disease,32 UC patients,and 31 healthy controls.The V3 and V4 regions of the 16S ribosomal RNA gene were sequenced on Illumina MiSeq platform to cover low taxonomic levels.Data were further processed in QIIME employing MaAsLin and LEfSe tools for analysis of the output data.RESULTSMicrobial profiles in both PSC and UC were characterized by low bacterial diversity and significant change in global microbial composition.Rothia,Enterococcus,Streptococcus,Veillonella,and three other genera were markedly overrepresented in PSC regardless of concomitant inflammatory bowel disease(IBD).Rothia,Veillonella and Streptococcus were tracked to the species level to identify Rothia mucilaginosa,Streptococcus infantus,S.alactolyticus,and S.equi along with Veillonella parvula and V.dispar.PSC was further characterized by decreased abundance of Adlercreutzia equolifaciens and Prevotella copri.Decrease in genus Phascolarctobacterium was linked to presence of colonic inflammation regardless of IBD phenotype.Akkermansia muciniphila,Butyricicoccus pullicaecorum and Clostridium colinum were decreased in UC along with genus Roseburia.Low levels of serum albumin were significantly correlated with enrichment of order Actinomycetales.CONCLUSIONPSC is associated with specific gut microbes independently of concomitant IBD and several bacterial taxa clearly distinguish IBD phenotypes(PSC-IBD and UC). 展开更多
关键词 Dysbiosis Inflammatory bowel disease Ulcerative colitis Gut microbiota Primary sclerosing cholangitis
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Regulated upon activation,normal T cell expressed and secreted(RANTES)levels in the peripheral blood of patients with Alzheimer’s disease 认领 引用 被引量：7
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作者 Gabriela Vacínová Daniela Vejražkova +6 位作者 Robert Rusina Iva Holmerová Hana Vaňková Eva Jarolímová Josef Včelák Běla Bendlová Markéta Vaňková 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第4期775-779,共5页
Alzheimer’s disease(AD)is the most common type of dementia,but it is very difficult to diagnose with certainty,so many AD studies have attempted to find early and relevant diagnostic markers.Regulated upon activation... Alzheimer’s disease(AD)is the most common type of dementia,but it is very difficult to diagnose with certainty,so many AD studies have attempted to find early and relevant diagnostic markers.Regulated upon activation,normal T cell expressed and secreted(RANTES,also known as C-C chemokine ligand)is a chemokine involved in the migration of T cells and other lymphoid cells.Changes in RANTES levels and its expression in blood or in cerebrospinal fluid have been reported in some neurodegenerative diseases,such as Parkinson’s disease and multiple sclerosis,but also in metabolic diseases in which inflammation plays a role.The aim of this observational study was to assess RANTES levels in peripheral blood as clinical indicators of AD.Plasma levels of RANTES were investigated in 85 AD patients in a relatively early phase of AD(median 8.5 months after diagnosis;39 men and 46 women;average age 75.7 years),and in 78 control subjects(24 men and 54 women;average age 66 years).We found much higher plasma levels of RANTES in AD patients compared to controls.A negative correlation of RANTES levels with age,disease duration,Fazekas scale score,and the medial temporal lobe atrophy(MTA)score(Scheltens’s scale)was found in AD patients,i.e.,the higher levels corresponded to earlier stages of the disease.Plasma RANTES levels were not correlated with cognitive scores.In AD patients,RANTES levels were positively correlated with the levels of pro-inflammatory cytokines interleukin-6 and tumor necrosis factor-α,which is consistent with the wellknown fact that AD is associated with inflammatory processes.RANTES levels were also positively correlated with insulin levels in AD patients,with insulin resistance(HOMA-R)and pancreatic beta cell function(HOMA-F).This study evaluated several clinical and metabolic factors that may affect plasma levels of RANTES,but these factors could not explain the increases in RANTES levels observed in AD patients.Plasma levels of RANTES appear to be an interesting peripheral marker for early stages of AD.The study was approved by the Ethics Committee of Institute of Endocrinology,Prague,Czech Republic on July 22,2011. 展开更多
关键词 Alzheimer’s disease biomarker central nervous system cognitive impairment inflammation RANTES
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The significance of cherts as markers of Ocean Plate Stratigraphy and paleoenvironmental conditions:New insights from the Neoproterozoic-Cambrian Blovice accretionary wedge,Bohemian Massif 认领 引用 被引量：3
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作者 LukášAckerman Jirízák +5 位作者 Václav Kachlík Jan Pašava KarelZák Andreas Pack František Veselovsky Ladislav Strnad 《Geoscience Frontiers》 SCIE CAS CSCD 2023年第1期162-180,共19页
The Ediacaran to early Cambrian Blovice accretionary complex,Bohemian Massif,hosts abundant chert bodies that formed on an oceanic plate and were involved in subduction beneath the northern margin of Gondwana.Field re... The Ediacaran to early Cambrian Blovice accretionary complex,Bohemian Massif,hosts abundant chert bodies that formed on an oceanic plate and were involved in subduction beneath the northern margin of Gondwana.Field relationships of cherts to their host,their microstructure and elemental as well as isotopic compositions revealed diverse processes of chert petrogenesis reflecting depositional environment and position on the oceanic plate.The deep-water cherts formed through a hydrothermal precipitation of silica-rich gels on outer trench swell of the subducted slab with none or only minor addition of terrigenous material.On the contrary,the shallow-water cherts formed in lagoons on seamount slopes,and at least some of them represent a product of hydrothermal replacement of former carbonate and/or evaporite precursors.For both chert types,the hydrothermal fluids were of low temperature and continuous pervasive hydrothermal alteration of oceanic crust,together with an elevated Si content in Neoproterozoic seawater,served as the major source of silica.On the other hand,minor carbon enrichment in chert is mostly linked to variable incorporation of organic matter that was deposited on the seafloor.Rare earth element(REE)systematics of the cherts indicate predominantly oxygenated environment for the shallow-water cherts whereas the deep-water cherts were deposited in diverse redox conditions,depending on their distance from hydrothermal vent.Using these data,we demonstrate that the cherts once formed a part of Ocean Plate Stratigraphy(OPS)now dismembered and mixed with terrigenous siliciclastic material to form OPS mélanges.Combining our data with those from the existing literature,we show that cherts can serve as significant markers of OPS since the Archean,recording a complex interplay between seafloor-related volcanic(production of MORB-and OIB-like magmas)and sedimentary processes,hydrothermal activity at mid-ocean ridges and seamount chains as well as at outer slopes of subducting slabs.However,the cherts also exhibit a secular change in composition and petrogenesis most profoundly affected by an overturn in seawater silica cycle across the Precambrian-Phanerozoic boundary. 展开更多
关键词 Chert Accretionary wedge Ediacaran Triple oxygen isotopes Strontium isotopes Ocean Plate Stratigraphy
Why not to avoid the smell of danger? Unexpected behavior of the Cypriot mouse surviving on the island invaded by black rats 认领 引用 被引量：2
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作者 Daniel FRYNT Margareta BALADOVA +2 位作者 Barbora ELIASOVA Silvie LISKOVA Eva LANDOVA 《Current Zoology》 SCIE CAS CSCD 2015年第4期781-791,共11页
Mus cypriaeus is a recently discovered endemic species that evolved about half a million years ago on the Cyprus Is- land in an absence of most mammalian predators and competitors. As on other Mediterranean islands, t... Mus cypriaeus is a recently discovered endemic species that evolved about half a million years ago on the Cyprus Is- land in an absence of most mammalian predators and competitors. As on other Mediterranean islands, the faunal composition was dramatically changed by the invasion of commensal and domestic species following Holocene colonization by humans. We exa- mined the behavioral responses of the Cypriot mouse to the odors of these new competitors （black and Norway rat, house mouse and spiny-mouse） and predator （domestic cat） as well as controls （Herb-field mouse, guinea pig）. We compared them with those of mainland population of house mouse from Syria with different coexistence history. Surprisingly, the Cypriot mouse failed to avoid the odor of its current main competitor, the black rat. Moreover, the response patterns of both the Cypriot and Syrian house mice to the examined odor sources appeared fairly comparable. There was a clear tendency to prefer odors of other murids over unscented sawdust as well as to avoid the odor of a domestic cat. In conclusion, neither the long-term isolation from predators nor the recent strong competition with black rats affected mice eompetitory and antipredatory responses fundamentally [Current Zoology 61 （4）： 781-791, 2015]. 展开更多
关键词 Competition Cyprus Mus cypriacus Odor preference Rattus rattus
Influence of COM-peptides/proteins on the properties of flocs formed at different shear rates 认领 引用 被引量：1
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作者 Monika Filipenska Petra Vasatova +5 位作者 Lenka Pivokonska Lenka Cermakova andrea Gonzalez-Torres Rita K.Henderson Jana Naceradska Martin Pivokonsky 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第6期116-127,共12页
Coagulation followed by floc separation is a key process for the removal of algal organic matter(AOM) in water treatment. Besides optimizing coagulation parameters,knowledge of the properties of AOM-flocs is essential... Coagulation followed by floc separation is a key process for the removal of algal organic matter(AOM) in water treatment. Besides optimizing coagulation parameters,knowledge of the properties of AOM-flocs is essential to maximizing AOM removal.However, the impact of AOM on the floc properties remains unclear. This study investigated how peptides/proteins derived from the cellular organic matter(COM) of the cyanobacterium Microcystis aeruginosa influenced the size, structure, and shape of flocs formed at different shear rates(G). Flocs formed by kaolinite, COM-peptides/proteins and a mixture of the same were studied, and the effect of intermolecular interactions between floc components on floc properties was assessed. The coagulation experiments were performed in a Taylor–Couette reactor, with aluminum(Al) or ferric sulphate(Fe) utilized as coagulants. Image analysis was performed to gauge floc size and obtain data on fractal dimension. It was found that floc properties were affected by the presence of the COM-peptides/proteins and the coagulant used. COM-peptides/proteins increased floc size and porosity and widened floc size distributions. The Fe coagulant produced larger and less compact flocs than Al coagulant. Moreover, the decrease in floc size that occurred in parallel with increase in shear rate was not smooth in progress. A rapid change for the kaolinite-coagulant suspension and two rapid changes for the suspensions containing COM were observed. These were attributed to various intermolecular interactions between floc components participating in coagulation at different G. Based on the results obtained, shear rates suitable for efficient separation of flocs containing COM were suggested. 展开更多
关键词 Algal organic matter Floc size Coagulation Image analysis Water treatment
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How to explore a new environment:exploratory tactics of the black rat(Rattus rattus) 认领 引用 被引量：1
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作者 Iveta Štolhoferová Veronika Rudolfová +2 位作者 Hana Skalíková Barbora Vobrubová Daniel Frynta 《Current Zoology》 SCIE CAS CSCD 2024年第3期371-382,共12页
The black rat(Rattus rattus)is a unique model for studying exploratory tactics due to its enormous colonizing potential.Considerable behavioral variability and consistent interindividual differences might help populat... The black rat(Rattus rattus)is a unique model for studying exploratory tactics due to its enormous colonizing potential.Considerable behavioral variability and consistent interindividual differences might help populations inhabit new environments and persist there even under intense pressure.Additionally,the affnity of the black rat for climbing might be another advantage,widening their potential niche.In this study,we describe the exploratory tactics of the black rats when introduced to a novel environment.In the frst experiment,we tested 12 rats and calculated repeatability of their behaviors across 12 sessions of an enriched open-feld test.We concluded that climbing is a highly repeatable behavior that serves as an important source of interindividual variability.In the second experiment,we tested 24 black rats in a unique L-shaped arena.Each rat was tested twice.We found that the majority of rats distributed their activity evenly,exploring each part of the apparatus for a similar amount of time,thus maximizing their chances of fnding resources.Nevertheless,these“even”explorers still greatly differed in their level of activity,orderliness and affnity for climbing,generating large variability.In contrast,the minority of rats concentrated their activity only on a section of the new environment and were therefore characterized as selective explorers.Overall,we concluded that a combination of such exploratory tactics as well as a bias for even explorers enables black rats to quickly colonize new environments and persist there even under unfavorable conditions. 展开更多
关键词 3D behavior climbing repeatability strategy.
Evidence of widespread hybridization among couch grasses(Elymus,Poaceae) 认领 引用 被引量：1
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作者 Romana Urfusova Vaclav Mahelka +1 位作者 Frantisek Krahulec Tomas Urfus 《Journal of Systematics and Evolution》 SCIE CAS CSCD 2021年第1期113-124,共12页
Hybridization,polyploidization,and crop-to-wild gene transfer within the agriculturally important tribe Triticeae are well explored experimentally,but the true consequences of both phenomena under natural conditions r... Hybridization,polyploidization,and crop-to-wild gene transfer within the agriculturally important tribe Triticeae are well explored experimentally,but the true consequences of both phenomena under natural conditions remain understudied.The present paper reports on an investigation of three species of couch grasses(Elymus hispidus,E.repens,and E.caninus)examining the ploidy levels and absolute genome sizes(1081 plants from 302 natural populations in Central Europe,verified by chromosome counts)and their morphological delimitation.In the present study,the hexapioid level prevailed in E.hispidus and E.repens whereas E.caninus was exclusively tetraploid.Introgressive hybridization between hexapioid species,unidirectionally shifted towards E.hispidus,was indicated by a continual pattern of genome size values.We did not find any evidence for heteroploid hybridization involving tetraploid E.caninus;however,we detected minority cytotypes among both E.caninus plants(hexapioid)and E.repens-E.hispidus hybrids(heptapioid and nonaploid)suggesting the formation of unreduced gametes.Morphometric results(367 plants,redundancy analysis,principal component analysis,and correlation analysis)mirrored the continual homoploid pattern of absolute genome size(including the unidirectional shift),and a significant correlation between absolute genome size and morphology was confirmed.Moreover,morphometric analyses detected additional characteristics for the delimitation of the Elymus taxa under study.Considering the crossability of E.hispidus with Triticum aestivum(bread wheat),the revealed extent of introgressive hybridization has implications for assessing the potential risk of gene flow between crops and troublesome weeds. 展开更多
关键词 absolute genome size couch grass Elymus hybridization introgression ploidy level Thinopyrum
Geographic variability in the alarm calls of the European ground squirrel 认领 引用 被引量：1
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作者 Irena SCHNEiDEROA Lucie Stefanska Lukas Kratochvil 《Current Zoology》 SCIE CAS CSCD 2020年第4期407-415,共9页
Geographic variability in vocalizations has been documented in many mammalian species. We examined to what extent it applies to the alarm calls of the European ground squirrel Spermophilus citellus. We recorded the ca... Geographic variability in vocalizations has been documented in many mammalian species. We examined to what extent it applies to the alarm calls of the European ground squirrel Spermophilus citellus. We recorded the calls of 82 adult individuals from 5 natural colonies in the Czech Republic and 24 adult individuals from an artificial seminatural colony located in a Czech zoo. The founders of this colony originated from 4 different natural colonies in the Czech Republic. Our results showed that there are hardly any differences in the acoustic structure of the alarm calls between male and female European ground squirrels. Discriminant function analysis showed the highest degree of discriminability for the most isolated sites (54-74% of individuals classified correctly), whereas the lowest degree of discriminability was found for 2 interconnected colonies (38-40% individuals classified correctly). Individuals from the artificial seminatural colony were often classified correctly to this colony (58% classified correctly);however, the precision of the classification was comparatively relatively low, that is, many individuals from other colonies were incorrectly classified into this seminatural colony. This likely corresponds to the different origins of its founders. These findings indicate that there is a rather substantial geographic variability in the alarm calls of the European ground squirrel, and our study highlights its possible impact on conservation measures such as establishing artificial colonies or reintroductions. 展开更多
关键词 artificial population intraspecies variability mammalian vocalization Rodentia Spermophilus citellus
Frequency-modulated second elements of two-element alarm calls do not enhance discrimination of callers in three Eura- sian ground squirrels 认领 引用 被引量：2
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作者 Irena SCHNEIDEROVA 《Current Zoology》 SCIE CAS CSCD 2012年第5期749-757,共9页
Alarm calls of the European Spermophilus citellus （EGS）, Taurus S. taurensis （TGS） and Anatolian S. xanthoprymnus （AGS） ground squirrels share the same basic structure. They are tonal sounds consisting primarily... Alarm calls of the European Spermophilus citellus （EGS）, Taurus S. taurensis （TGS） and Anatolian S. xanthoprymnus （AGS） ground squirrels share the same basic structure. They are tonal sounds consisting primarily of two different elements. The first element, often produced without the second element, has limited frequency modulation, while the second element is more frequency modulated. The present study examined whether this frequency-modulated element enhances the individual distinc- tiveness of calls, allowing calls to be ascribed with greater confidence to individual callers of the three species. Cross-validated discriminant function analysis （DFA） based on five acoustic parameters of the first element successfully classified calls to correct individuals （EGS： 90%, TGS： 98%, AGS： 96%）. Cross-validated DFA based on five acoustic parameters of the second element was also successful in classifications （EGS： 88%, TGS： 86%, AGS： 96%）, though discrimination of callers based on parameters of the second versus first element was the same for the AGS, lower for the EGS and significantly lower for the TGS. Cross-validated DFA based on five acoustic parameters of two-element calls also successfully classified calls to correct individu- als （EGS： 93%, TGS： 98%, AGS： 97%）, though did not improve the extent to which calls could be classified to individuals be- yond that based on the ftrst element alone. Thus, the second element does not enhance the individual distinctiveness of calls, but may convey other information such as the location of the caller [Current Zoology 58 （5）： 749-757, 2012]. 展开更多
关键词 Alarm call Ground squirrel Individual recognition Spermophilus citeUus Spermophilus taurensis Spermophilusxanthoprymnus
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