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Changes in the adult sex ratio of six duck species breeding populations over two decades

Avian Research 2024年第2期15卷 202-210页

作者： Monika Homolkova Petr Musil Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova s.rka neuzilova Jan Zouhar Department of Ecology Faculty of Environmental SciencesCzech University of Life Sciences PragueKamýcka 129CZ-16521Prague–SuchdolCzech Republic Department of Terrestrial Ecology Norwegian Institute for Nature Research(NINA)PO Box 5685 TorgardenTrondheimN-7485Norway Department of Econometrics Faculty of Informatics and StatisticsUniversity of Economicsnam.W.Churchilla 4CZ-13067Prague 3Czech Republic

Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered *** with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction *** this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in south Bohemia,Czechia,between 2004 and *** evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in *** determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and *** the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early ***,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population.

关键词： Adult sex ratio Breeding population Population dynamics Red-listed species Waterfowl Winter weather conditions

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Why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

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Forest Ecosystems 2024年第1期11卷 24-31页

作者： Goran ståhl Terje Gobakken svetlana saarela Henrik J.Persson Magnus Ekstrom sean P.Healey Zhiqiang Yang Johan Holmgren Eva Lindberg Kenneth Nystrom Emanuele Papucci Patrik Ulvdal Hans OleØrka Erik Næsset Zhengyang Hou Håkan Olsson Ronald E.McRoberts Department of Forest Resource Management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of Environmental sciences and Natural Resource Management Norwegian University of Life SciencesÅsNorway UsDA Forest service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing100083China Department of Forest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adjustments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias Model-based inference Design-based inference

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Novel therapeutic strategies and common mechanisms of neurodegenerative diseases

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Neuroprotection 2024年第2期2卷 65-66页

作者： s.rka Lehtonen Jukka Jolkkonen A.I.Virtanen Institute for Molecular sciences University of Eastern Finland Kuopio Finland

Neuroprotection holds particular significance in neurodegenerative diseases characterized by the death of brain *** differences in timeframe,location,pathology,and clinical outcomes,common pathophysiological mechanisms may exist,including oxidative stress and *** far,neuroprotective therapies have yet to demonstrate significant benefits in clinical trials.1 Reasons for past translational failures may involve low experimental study quality,more complex pathophysiology than expected,challenging drug delivery,late intervention,and safety ***,recent advances offer renewed hope and potential breakthroughs that could change the treatment landscape in the *** novel therapeutic strategies will be discussed in this issueofNeuroprotection.

关键词： brain-derived neurotrophicfactor(BDNF) drug repositioning gut microbiota neuroprotection oxidative stress Parkinson's disease stroke

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Mirai Botnet Attack Detection in Low-scale Network Traffic

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Intelligent Automation & soft Computing 2023年第7期37卷 419-437页

作者： Ebu Yusuf GÜVEN Zeynep GÜrka¸s-AYDIN Department of Computer Engineering Istanbul University-CerrahpasaIstanbulTurkey

The Internet of Things(IoT)has aided in the development of new products and *** to the heterogeneity of IoT items and networks,traditional techniques cannot identify network ***-based solutions make it challenging to secure and manage IoT devices and services due to their *** the use of artificial intelligence eliminates the need to define rules,the training and retraining processes require additional processing *** study proposes a methodology for analyzing constrained devices in IoT *** examined the relationship between different sized samples from the Kitsune dataset to simulate the Mirai attack on IoT *** training and retraining stages for the Mirai attack were also evaluated for *** approaches are evaluated in smaller sample sizes to minimize training time on low-resource ***-validation was used to avoid overfitting classification methods during the learning *** used the Bootstrapping technique to generate 1000,10000,and 100000 samples to examine the performance metrics of different-sized variations of the *** this study,we demonstrated that a sample size of 10000 is sufficient for 99,56%accuracy and learning in the detection of Mirai attacks in IoT devices.

关键词： Mirai internet of things low-scale traffic machine learning intrusion detection

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Double-brooding and annual breeding success of great tits in urban and forest habitats

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Current Zoology 2022年第5期68卷 517-525页

作者： Boglárka Bukor Gábor seress Ivett Pipoly Krisztina sándor Csenge sinkovics ErnőVincze András Liker Behavioral Ecology Research Group Center for Natural SciencesUniversity of PannoniaVeszprém H-8200Hungary MTA-PE Evolutionary Ecology Research Group University of PannoniaVeszprém H-8200Hungary MTA-ELTE Comparative Ethology Research Group BudapestHungary Department of Biology Theoretical Population Ecology and Evolution GroupLund UniversityLundSweden

Urban areas differ from natural habitats in several environmental features that influence the characteristics of animals living *** example,birds often start breeding seasonally earlier and fledge fewer offspring per brood in cities than in natural ***,longer breeding seasons in cities may increase the frequency of double-brooding in urban compared with nonurban populations,thus potentially increasing urban birds’annual reproductive output and resulting in lower habitat difference in reproductive success than estimated by studies focusing on first clutches *** this study,we investigated 2 urban and 2 forests great tit Parus major populations from 2013 to *** compared the probability of double-brooding and the total number of annually fledged chicks per female between urban and forest habitats,while controlling for the effects of potentially confounding *** was a trend for a higher probability of double-brooding in urban(44%of females)than in forest populations(36%),although this was not consistent between the 2 urban *** produced significantly fewer fledglings annually in the cities than in the forest sites,and this difference was present both within single-and double-brooded ***,double-brooded urban females produced a similar number of fledglings per season as single-brooded forest *** results indicate that double-brooding increases the reproductive success of female great tits in both habitats,but urban females cannot effectively compensate in this way for their lower reproductive output per ***,other mechanisms like increased post-fledging survival can mitigate habitat differences in reproductive success.

关键词： annual reproductive success habitat differences population self-sustainability second brood urban conservation

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Detecting the presence of natural forests using airborne laser scanning data

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Forest Ecosystems 2023年第6期10卷 668-680页

作者： Marie-Claude Jutras-Perreault Terje Gobakken Erik Næsset Hans OleØrka Faculty of Environmental sciences and Natural Resource Management Norwegian University of Life SciencesNMBUP.O.BoxNO-1432ÅsNorway

Centuries of forest exploitation have caused significant loss of natural forests in Europe,leading to a decline in populations for many *** prevent further loss in biodiversity,the Norwegian government has set a target of protecting 10%of the forested ***,recent data from the National Forest Inventory(NFI)reveals that less than 2%of Norway's forested area consists of natural *** identify forests with high conservation value,we used vertical and horizontal variables derived from airborne laser scanning(ALs)data,along with NFI plot *** study aimed to predict the presence of natural forests across three counties in southeastern Norway,using three different definitions:pristine,near-natural,and semi-natural *** forests are scarce,and their underrepresentation in field reference data can compromise the accuracy of the *** address this,we assessed the potential gain of including additional field data specifically targeting natural forests to achieve a better balance in the ***,we examined the impact of stratifying the data by dominant tree species on the performance of the *** results revealed that semi-natural forests were the most accurately predicted,followed by near-natural and pristine forests,with Matthews correlation coefficient values of 0.32,0.24,and 0.17,*** additional field data did not improve the ***,stratification by species improved the accuracy of predictions for near-natural and semi-natural forests,while reducing accuracy for pristine *** use of horizontal variables did not improve the *** study demonstrates the potential of ALs data in identifying forests with high conservation *** provides a basis for further research on the use of ALs data for the detection and conservation of natural forests,offering valuable insights to guide future forest preservation efforts.

关键词： Natural forest ALs Naturalness Vertical variables Horizontal variables Biodiversity Forest condition Ecosystem services

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乙烷氧化脱氢用Ni/Al_2O_3催化剂中活性镍物种前驱体(英文)

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催化学报 2013年第10期34卷 1905-1913页

作者： Lucie smoláková árka Botková Libor apek Peter Priecel Agnieszka soltysek Martin Kout Lenka Matějová Department of Physical Chemistry Faculty of Chemical TechnologyUniversity of Pardubice Nanotechnology Centre V B-Technical University of Ostrava

Ni/Al2O3 catalysts for oxidative dehydrogenation(ODH) of ethane were prepared by impregnation of Al2O3 with nickel acetate or nickel nitrate,and by mechanical mixing of NiO and *** Ni-based catalysts were characterized by N2 adsorption-desorption,X-ray diffraction,diffuse reflectance UV-visible diffuse reflectance spectroscopy,and temperature-programmed reduction of *** results showed that formation of crystalline NiO particles with a size of stoichiometric NiO species in the Ni/Al2O3 catalysts led to more active species in ODH of ethane under the investigated reaction *** contrast,tetrahedral Ni species present in the catalysts led to higher selectivity for *** of large crystalline NiO particles(22-32 nm) over Ni/Al2O3 catalysts decreased the selectivity for ethene.

关键词： Alumina Ethane Oxidative dehydrogenation Nickel species

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Integration of chemical fractionation, M?ssbauer spectrometry, and magnetic methods for identification of Fe phases bonding heavy metals in street dust

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Journal of Environmental sciences 2023年第2期 875-891页

作者： Beata Górka-Kostrubiec Ryszard ?wietlik Tadeusz szumiata sylwia Dyt?ow Marzena Trojanowska Institute of Geophysics Polish Academy of Sciences Department of Environmental Chemistry and Engineering University of Technology and Humanities in Radom 3. Department of Physics Faculty of Mechanical Engineering University of Technology and Humanities in Radom

street dust is one of the most important carriers of heavy metals(HMs) originating from natural and anthropogenic sources. The main purpose of the work was to identify which of Fe-bearing phases bind HMs in street dust. Magnetic parameters of the Fe-bearing components, mainly magnetically strong iron oxides, are used to assess the level of HM *** sequential extraction combined with magnetic methods(magnetic susceptibility,magnetization, remanent magnetization) allowed determining the metal-bearing fractions and identifying the iron forms that are mostly associated with traffic-related HMs. The use of M?ssbauer spectrometry(Ms) supplemented by magnetic methods(thermomagnetic curves and psarameters of hysteresis loops) enabled precise identification and characterization of iron-containing minerals. The classification of HMs into five chemical fractions differing in mobility and bioaccessibility revealed that iron is most abundant(over 95%) in the residual fraction followed by the reducible fraction. HMs were present in reducible fraction in the following order: Pb>Zn>Mn>Cr>Ni>Fe>Cu, while they bound to the residual fraction in the following order: Fe>Ni>Cr>Mn>Pb>Cu>Zn. The signature of the anthropogenic origin of street dust is the presence of strongly nonstoichiometric and defected grains of magnetite and their porous surface. Magnetite also occurs as an admixture with maghemite, and with a significant proportion of hematite. A distinctive feature of street dust is the presence of metallic iron and iron carbides. Magnetic methods are efficient in the screening test to determine the level of HM pollution, while Ms helps to identify the iron-bearing minerals through the detection of iron.

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silver flr tree-ring fluctuations decrease from north to south latitude—total solar irradiance and NAO are indicated as the main influencing factors

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Forest Ecosystems 2023年第6期 717-731页

作者： Václav ?im?nek Anna Prok?pková Zdeněk Vacek stanislav Vacek Jan Cukor Jirí Reme? Vojtěch Hájek Giuseppe D'Andrea Martin ?álek Paola Nola Osvaldo Pericolo ?árka Holzbachová Francesco Ripullone Faculty of Forestry and Wood sciences Czech University of Life Sciences Prague Forestry and Game Management Research Institute 3. Czech Academy of sciences Institute of Vertebrate Biology Faculty of Environmental sciences Czech University of Life Sciences Prague Department of Earth and Environmental sciences University of Pavia Forests of the Czech Republic SOE school of Agricultural Forestry and Environmental Sciences University of Basilicata

silver flr(Abies alba Mill.) is a flexible European tree species, mainly vegetating within the mountainous regions of Europe, but its growth responses across its latitudinal and longitudinal range have not yet been satisfactorily verifled under changing environmental conditions. This study describes the tree-ring increment of silver flr in research plots across a latitudinal gradient from the northern range in Czechia(CZ), through Croatia(HR) to the southernmost range in Italy(IT). The research aims to analyze in detail the dynamics and cyclicity of the ringwidth index(RWI) and how it relates to climatic factors(temperature and precipitation), the North Atlantic Oscillation(NAO), and total solar irradiance(TsI), including the determination of latitude. The results show that the main drivers affecting flr growth are the seasonal NAO index and TsI. Monthly temperatures affect RWI early in the vegetation season, while lack of precipitation during the summer is a limiting factor for flr growth,especially in July. seasonal temperatures and temperatures in June and July negatively impact, while seasonal precipitation totals in the same months positively influence the RWI in all research plots across meridian. The longest growth cycles in flr RWI were recorded in the northernmost studied plots in CZ. These cyclical fluctuations recede approaching the south. The cyclic increase in RWI is related to the TsI, which decreases its effect from north to south. The TsI?s effects vary, positively impacting CZ but negatively influencing HR while remaining relatively neutral in IT. On the other hand, seasonal NAO tends to negatively affect silver flr growth in HR and CZ but has a mildly positive effect in IT. In conclusion, the TsI and the influence of the seasonal NAO index are prevalent in the flr RWI and are accompanied by a greater cyclicity of RWI in Central Europe(temperature optimum) than in the Italian Mediterranean region, where this tree species is limited by climatic condi

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Factors Controlling Low Uranium and Thorium Concentrations in the Cayirhan Bituminous shales(CBs)in the Beypazari(Ankara)Area,Turkey

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Acta Geologica sinica(English Edition) 2014年第1期88卷 248-252,I0009,I0010,253-259页

作者： Berna Yavuz PEHLIVANLI sükrü KOC Ali sARI Hilal ENGIN Department of Geological Engineering Faculty of Engineering and Architecture Bozok University Department of Geological Engineering Faculty of Engineernig Ankara University Graduate school of Natural and Applied sciences Ankara University

In this study uranium and thorium contents and depositional characteristics of ay rhan bituminous shales（ Bs）, west of Ankara（central Anatolia）, are investigated. samples used were collected from boreholes opened by Park Holding Ltd. A total of 25 samples were taken from bituminous shale levels in boreholes drilled at 6 different locations in the study area. The H rka formation which hosts bituminous shale deposits is a volcanosedimentary sequence and all lithofacies indicate that a lacustrine environment where the water level was continuously changed. In addition to hydrocarbon generation potential, bituminous shales also accumulate significant amount of radioactive elements such as uranium and thorium. The average uranium and thorium concentrations of Bs（1.83/2.62 ppm） are much lower than averages of UC, NAsK and PAAs（uranium： 2.70/2.66/3.10 ppm; thorium： 8.50/12.30/14.60 ppm）. Low uranium contents in comparison to those of similar lacustrine environments might be attributed to that waters of depositional environment of Bs contain low concentration of dissolved uranium and redox conditions were of oxic and dioxic character. Correlation data indicate that U and Th have a similar source and are associated predominantly with clays and phosphates and dominantly with organic material. Radioactive elements in the basin might be derived from Paleozoic granites and metamorphites（e.g. gneiss, schist） which comprise the basement and volcanism which was active in the region throughout the Miocene period. These elements are probably associated with uraniferous phosphate minerals（e.g. autunite, torbernite） which occur in granite, gneiss and schist. Bs with average TOC content of 10.96 % shows very good/perfect source rock potential. Positive correlations between Gamma-Ray values and U, Th and K concentrations imply that radioactivity might be originated from these three elements.

关键词： Uranium and Thorium concentrations ay rhan bituminous shales Beypazar area Turkey

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