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Integral terminal sliding mode augmented finite-time visual servo control of omni-directional mobile manipulators 被引量:1
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作者 Yuanji Liu Tianyu Zhu +1 位作者 Qingdu Li Jianwei Zhang 《Control Theory and Technology》 2025年第2期193-206,共14页
This paper presents a robust finite-time visual servo control strategy for the tracking problem of omni-directional mobile manipulators(OMMs)subject to mismatched disturbances.First,the nonlinear kinematic model of vi... This paper presents a robust finite-time visual servo control strategy for the tracking problem of omni-directional mobile manipulators(OMMs)subject to mismatched disturbances.First,the nonlinear kinematic model of visual servoing for OMMs with mismatched disturbances is explicitly presented to solve the whole-body inverse kinematic problem.Second,a sliding mode observer augmented with an integral terminal sliding mode controller is proposed to handle these uncertainties and ensure that the system converges to a small region around the equilibrium point.The boundary layer technique is employed to mitigate the chattering phenomenon.Furthermore,a strict finite-time Lyapunov stability analysis is conducted.An experimental comparison between the proposed algorithm and a traditional position-based visual servo controller is carried out,and the results demonstrate the superiority of the proposed control algorithm. 展开更多
关键词 Omni-directional mobile manipulators Nonlinear kinematic model Mismatched disturbances Integral terminal sliding mode control Finite-time control
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The Common Bottlenose Dolphins (Tursiops truncatus) Song
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作者 Nicholovich Rose 《Open Journal of Animal Sciences》 2025年第1期1-29,共29页
A 1.5-hour recording of six (Gulf of Mexico) captive common bottlenose dolphins (Tursiops truncatus) at Sea Life Park, Hawaii shows that: 1) they have a song of a sequence of tonal (often slurred) notes. The evidence ... A 1.5-hour recording of six (Gulf of Mexico) captive common bottlenose dolphins (Tursiops truncatus) at Sea Life Park, Hawaii shows that: 1) they have a song of a sequence of tonal (often slurred) notes. The evidence for their song comes from: a) their emitting songs that were complex (both tonally and rhythmically), b) their likely improvising (as inferred from their most complex songs not being repeated), c) songs based on a theme (used repeatedly), d) a bout of singing (at times) including social creativity, e) songs with a distinct beginning, middle and end section, and f) one song consisting of in part, a theme, 2) their songs are not sung in key (as determined from analysing the beginning tonal value of a note with spectral-frequency analysis), and 3) are sung in bouts, and 4) mostly with tonal-striated vocalizations (in the literature termed squawks and bray calls). Their apparent creativity (likely improvisations) and social creativity are of importance to how they evolved cognitively, to the study of song culture (between populations and delphinid species), understanding their (intra and inter-species) associations, and kinds of relationships, determining individual personalities, and perhaps will provide supporting evidence for their ability to reason. As inferred, they sing without being intentionally manipulative from: 1) their use of Gquic psychology [1] (as explained in this article), and 2) as inferred from their likely having an ability to reason [1] [2] (as deduced from their behavioural ecology (their unique exceptional evolutionary freedom), including their comparatively peaceful composure between conspecifics, in line with the proof of The Peaceful Composure Theorem), suggesting (per The Peaceful Composure Theorem) they have an egalitarian-like society. Their interspecies (displaced) aggression towards smaller odontocete species is shown to be a function of jealousies that emerge from their stronger social bonds than other species, from their compassionate nature, and females and males not pairing up in long-term associations. Species with greater cultural freedom are shown to have a more complex song providing further evidence for species culture not crucial to survival. The conclusive evidence for specie culture from my recent publications is of relevance to the scientific community’s acceptance of two new theories of evolution, and Gquic psychology. The loud burst-pulse sounds, chasing, charging and raking behaviours described in the literature could be a play behaviour, ought not be labelled as aggressive behaviours, as inferred from dog mock-fight play behaviour. In regard to future comparative behavioural ecology studies, aggressive animal behaviour should only be defined as an act of displacement (that is shown to commonly occur in the Indo-Pacific bottlenose dolphin species (Tursiops aduncus)), or as acts of biting, and hitting. 展开更多
关键词 Animal Behaviour Animal Communication Common Bottlenose Dolphin Song Delphinids Dolphin Behaviour ETHOLOGY Evolution Freedom to Intellectualize Theory Mebir Innate Response Music Peaceful Composure Theorem Psychology Social Creativity SOCIOLOGY Theory of Cultural and Evolutionary Freedom Tursiops truncatus
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Dieback of spruce plantations:Deadwood stands and management heterogeneity enhance beetle diversity and habitat connectivity
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作者 Eva Plath Kim Ehringhausen +5 位作者 Laura Griebel Leon Martiny Michel Schmitz Katharina Schreek Christoph Thiem Klaus Fischer 《Forest Ecosystems》 2025年第1期121-135,共15页
Forest ecosystems are important for biodiversity conservation and human societies,but are under pressure due to climate change and human interventions.This applies to natural forests as well as tree plantations.The la... Forest ecosystems are important for biodiversity conservation and human societies,but are under pressure due to climate change and human interventions.This applies to natural forests as well as tree plantations.The latter are globally widespread and therefore gaining increasing importance for biodiversity conservation.However,even after dieback due to increasing disturbance frequencies,such plantations are primarily managed for economic returns,leading to growing conflicts among stakeholders.In particular,the impact of forest management on biodiversity is being discussed.This study investigates the effects of five management approaches in a landscape severely affected by spruce(Picea abies L.)dieback on beetle diversity,conservation,and community composition.We considered direct effects of management and indirect effects of environmental parameters separately in ground-dwelling and flight-active beetles.Beetle diversity was strongly affected by forest management,with nonintervention deadwood stands being most beneficial for beetles.In addition,we show indirect effects of environmental factors.In general,parameters related to salvage logging(e.g.open canopies,tree stumps)influenced beetle diversity and conservation negatively,while positive effects were found for soil nutrient availability and plant species richness.Community composition differed strongly among management categories and indicated a lack of landscape connectivity for open habitat species,as we found only low proportions of such species even on salvage-logged sites.We propose a mixture of management approaches after bark beetle outbreaks,including a substantial proportion of non-intervention deadwood stands,to increase landscape heterogeneity and connectivity.This may increase overall biodiversity while addressing the concerns of both forestry and species conservation. 展开更多
关键词 Ips typographus Post-disturbance management Coleoptera Natural disturbances Biodiversity loss Beetle assemblages Nature conservation Forest dieback
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Impact of Terroir on Some Morphophysiological Parameters of Grapevines in Four Agroecological Zones of Côte d’Ivoire
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作者 Kouakou Thomas Yao Oi Kouadio Samuel Kouadio +1 位作者 Idrissa Coulibaly Tanoh Hilaire Kouakou 《Journal of Agricultural Chemistry and Environment》 2025年第1期1-22,共22页
Grapes are the main reason why the grapevine (Vitis vinifera L.) is cultivated. However, climate, soil conditions, vegetation and anthropogenic effects on the soil greatly affect grapevine production. The organoleptic... Grapes are the main reason why the grapevine (Vitis vinifera L.) is cultivated. However, climate, soil conditions, vegetation and anthropogenic effects on the soil greatly affect grapevine production. The organoleptic properties of grape-derived products, such as wine, are influenced by these factors, which are becoming increasingly popular in Africa. Thus, grapevines, which are commonly grown in warm regions, are acclimatized in Africa using grapevine varieties that can adjust to tropical conditions. This study, which was carried out in 2019, aimed to promote grapevine cultivation in Côte d’Ivoire by examining the influence of pedoclimatic factors on the agro-physiological characteristics of grapevines. In Côte d’Ivoire, there were four distinct agro-ecological zones (North, South, Southeast and West) where three grapevine varieties, Bequignol, Muscat Rouge and Aleatico, were grown. Grapevine plants could grow robustly in morpho-physiological ways because the soils had sufficient fertility, as revealed by the analysis of experimental sites. Grapevine varieties have successfully adapted to different terroirs, with the exception of Muscat Rouge, which only displayed favorable morphological characteristics in the Man zone (West). Regardless of the grape variety, the regions with the best grapevine-growing conditions were Man (West), followed by Aboisso (Southeast). Consequently, grapevine development was less favorable in Korhogo (North) and Abidjan (South) zones. Thus, the cultivation of grapevine varieties in Côte d’Ivoire was greatly influenced by terroir. 展开更多
关键词 Vitis vinifera Pedoclimatic Factors Bequignol Muscat Rouge Aleatico
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Reversible phase transition poly(benzyl methacrylate)/ionic liquid electrolytes for effective overheating protection in lithium batteries
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作者 Qian Yu Wei Sun +10 位作者 Jialing Zhu Haoxiang Li Shuai Wang Longqing Huang Qian Qiu Haoran Tian He Miao Fu Wang Chunfei Zhang Jinliang Yuan Lan Xia 《Journal of Energy Chemistry》 2025年第2期76-86,I0003,共12页
Battery safety is influenced by various factors,with thermal runaway being one of the most significant concerns.While most studies have concentrated on developing one-time,self-activating mechanism for thermal protect... Battery safety is influenced by various factors,with thermal runaway being one of the most significant concerns.While most studies have concentrated on developing one-time,self-activating mechanism for thermal protection,such as temperature-responsive electrodes,and thermal-shutdown separators,these methods only provide irreversible protection.Recently,reversible temperature-sensitive electrolytes have emerged as promising alternatives,offering both thermo-reversibility and self-protective properties.However,further research is crucial to fully understand these thermal-shutdown electrolytes.In this study,we propose lower critical solution temperature(LCST)phase behavior poly(benzyl methacrylate)/imidazolium-based ionic liquid mixtures to prepare temperature-sensitive electrolytes that provide reversible thermal shutdown protection of batteries.This electrolyte features an appropriate protection temperature(~105℃)and responds quickly within a 1 min at 105℃,causing cells to hardly discharge as the voltage suddenly drops to 3.38 V,and providing efficient thermal shutdown protection within 30 min.Upon cooling back to room temperature,the battery regains its original performance.Additionally,the electrolyte exhibits excellent cycling stability with the capacity retention of the battery is 91.6%after 500 cycles.This work provides a viable solution for preventing batteries from thermal runaway triggered by overheating. 展开更多
关键词 Lithium-ion battery Safety OVERHEATING Thermal runaway lonic liquid Lower critical solution temperature
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Advanced applications of pulsed laser deposition in electrocatalysts for hydrogen-electric conversion systems
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作者 Yuanyuan Zhou Yong Wang +4 位作者 Ke Zhang Huaqian Leng Peter Müller-Buschbaum Nian Li Liang Qiao 《Opto-Electronic Advances》 2025年第11期1-20,共20页
Pulsed laser deposition(PLD),as an advanced synthesis technology with unparalleled control over thin films,has evolved into a universal platform for optoelectronic materials engineering.Its unique advantages including... Pulsed laser deposition(PLD),as an advanced synthesis technology with unparalleled control over thin films,has evolved into a universal platform for optoelectronic materials engineering.Its unique advantages including precise stoichiometric transfer,heterogeneous structure preparation and in-situ monitoring enable the design of opto-electrocatalysts with controllable active sites.Traditional methods struggle to pinpoint active sites in hydrogen technologies such as fuel cells and water electrolysis,impeding catalyst customization and mechanistic understanding.Nevertheless,PLD remains underused here despite its outstanding performances in targeted photo-assisted electrocatalysts design.This review systematically explores the breakthrough achievements and provides detailed insights into photo-enhanced water electrolysis and fuel cells based on PLD.Beginning with the fundamentals of epitaxial film growth and film classification,particularly emphasis the related in situ optical analysis techniques.It subsequently highlights recent advances in electro-oxidation and reduction reactions of H_(2)and O_(2),demonstrating the control capabilities of PLD in precisely correlating the structure and activity at the atomic level.Finally,the review concludes by proposing scalable fabrication strategies and performance optimization frameworks to bridge fundamental insights with industrial-scale optoelectronic integration systems. 展开更多
关键词 pulse laser deposition oxygen reduction reaction oxygen evolution reaction hydrogen oxidation reaction hydrogen evolution reaction
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Direct Observation of Early-Stage Polymer Crystallization Driven by Surface Wrinkling and Compressive Stress in Thin Films
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作者 Peng Zhang Stephan V.Roth +1 位作者 Peter Muller-Buschbaum Tian-Bai He 《Chinese Journal of Polymer Science》 2025年第2期360-367,共8页
The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surfa... The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surface wrinkling precedes nucleation and crystal growth.This study examined the relationship between surface wrinkling,nucleation,and the formation of crystalline supramolecular structures using atomic force microscopy(AFM)and X-ray scattering measurements.Surface wrinkling is attributed to curving induced by accumulated stresses,including residual stress from the sample preparation and thermal stress during cooling.These stresses cause large-scale material flow and corresponding changes in the molecular conformations,potentially reducing the nucleation barrier.This hypothesis is supported by the rapid crystal growth observed following the spread of surface wrinkles.Additionally,the surface curving of the polymer thin film creates local minima of the free energy,facilitating nucleation.The nuclei subsequently grow into crystalline supramolecular structures by incorporating polymer molecules from the melt.This mechanism highlights the role of localized structural inhomogeneity in the early stages of crystallization and provides new insights into structure formation processes. 展开更多
关键词 Polymer crystallization NUCLEATION Surface wrinkling Stress Thin film
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Impact of anthropogenic pressure on the formation of population structure and genetic diversity of raccoon dog Nyctereutes procyonoides 被引量:4
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作者 Loreta GRICIUVIENE Algimantas PAULAUSKAS +2 位作者 Jana RADZIJEVSKAJA Judita ZUKAUSKIENE Irma PURAITE 《Current Zoology》 SCIE CAS CSCD 2016年第5期413-420,共8页
The raccoon dog Nyctereutes procyonoides experienced an active introduction and acclimatization in the European part of Russia followed by its migration to and colonization in the neighboring countries. Eventually, it... The raccoon dog Nyctereutes procyonoides experienced an active introduction and acclimatization in the European part of Russia followed by its migration to and colonization in the neighboring countries. Eventually, it has spread rapidly into many European countries. N. procyonoides probably invaded Lithuania from the neighboring countries of Belarus and Latvia where the species was introduced. However, the data on genetic diversity and population structure of the raccoon dogs in the recently invaded territories are still scarce. The objectives of this study were to investigate genetic diversity of N. procyonoides in Lithuania after acclimatization, and to assess the impact of anthropogenic pressure on the formation of population structure. A total of 147 N. procyonoides individuals collected from different regions of Lithuania were genotyped using 17 microsatellite markers. The microsatellite analysis of raccoon dogs indicated high levels of genetic diversity within the population. The Bayesian clustering analysis in STRUCTURE identified 4 genetic clusters among sampled raccoon dogs that could not reveal a clear separation between subpopulations. The widespread distribution of raccoon dogs in Lithuania, high level of genetic variation observed within subpopulations, and low level of variation portioned among subpopulations suggest migration and gene flow among locations. The significant correlation between genetic and geographic distances indicated isolation that reflected the distance between locations. The fencing of highways and very intensive traffic could be barriers to gene flow between the western and eastern sampling areas of raccoon dogs. 展开更多
关键词 Nyctereutes procyonoides microsatellite loci INVASION genetic diversity Lithuania.
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First Psocodean (Psocodea,Empheriidae) from the Cretaceous Amber of New Jersey 被引量:2
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作者 Dany AZAR Andre NEL Julian F.PETRULEVICIUS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第4期762-767,共6页
Representatives of the extinct psocid family Empheriidae are known from Eocene Baltic amber, Lowermost Eocene French amber (Oise), and Lower Cretaceous Spanish amber (Alava). We report herein the first discovery o... Representatives of the extinct psocid family Empheriidae are known from Eocene Baltic amber, Lowermost Eocene French amber (Oise), and Lower Cretaceous Spanish amber (Alava). We report herein the first discovery of an empheriid psocid from the Cretaceous amber of New Jersey as Jerseyempheria grimaldii gen. et sp. nov. The fossil is figured and described. The new species is distinguished from related taxa. A discussion and checklist of Empheriidae are provided. 展开更多
关键词 PSOCODEA Trogiomorpha Atropetae Empheriidae TURONIAN Cretaceous amber New Jersey USA
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Combined Effect of Nutrient and Pest Management on Soil Ecological Quality in Hybrid Rice Double-Cropping System 被引量:2
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作者 A.SUBHANI 《Pedosphere》 SCIE CAS CSCD 2003年第2期129-138,共10页
The mineral fertilizers (NPK) and pesticide, including herbicides, insecticides and fungicides, were applied alone or in combination and the soil sampling was done at different growth stages during the crop cycle to s... The mineral fertilizers (NPK) and pesticide, including herbicides, insecticides and fungicides, were applied alone or in combination and the soil sampling was done at different growth stages during the crop cycle to study the changes in soil organic matter, microbial biomass and their activity parameters in a paddy soil with different nutrient and pest management practices in a hybrid rice double-cropping system. A consistent increase in the electron transport system (ETS) activity was measured during the different crop growth stages of rice. The use of fertilizers (NPK) alone or with pesticides increased ETS activity, while a decline of ETS activity was noticed with pesticides alone as compared with the control. Nearly an increasing trend in soil phenol content was observed with the progression of crop growth stages, while the usage of pesticides alone caused maximum increments in the soil phenol content. The soil protein content was found nearly stable with fertilizers and/or pesticides application at various growth stages in both crops taken. But notable changes were noticed at different growth stages probably because of fluctuations in moisture and temperature at particular stages, which might have their effects on N mineralization. Marked depletions in the phospholipid content were found with the advancement of crop growth stages, while the incorporation of fertilizers and/or pesticides also produced slight changes, in which a higher decline was noticed with pesticide application alone compared with the control. 展开更多
关键词 electron transport system (ETS) hybrid rice PHENOL PHOSPHOLIPID PROTEIN
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Challenges and opportunities in the production of magnesium parts by directed energy deposition processes 被引量:2
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作者 Gürel Cam Ali Günen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1663-1686,共24页
Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aero... Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport industries.However,their widespread application is hindered by their low formability at room temperature due to limited slip systems.Cast Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high scrap.While casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain applications.Although metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast counterparts.Thus,MAM is a promising technique to produce Mg alloy parts.Directed energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive processes.However,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this technology.This review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and prospects.Furthermore,the predominant imperfections,notably inhomogeneous microstructure evolution and porosity,observed in Mg-alloy components manufactured through DED are discussed.Additionally,the preventive measures implemented to counteract the formation of these defects are explored. 展开更多
关键词 Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate
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Effects of Central Administration of Glutamine and Alanine on Feed Intake and Hypothalamic Expression of Orexigenic and Anorexigenic Neuropetides in Broiler Chicks 被引量:3
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作者 Khondowe Paul WANG Song-bo +8 位作者 CHEN Sheng-feng YU Jian-jian ZHU Xiao-tong WANG Li-na GAO Ping XI Qian-yun ZHANG Yong-liang SHU Gang JIANG Qing-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第7期1173-1180,共8页
Different amino acids have been shown to affect feed intake when injected directly into the central nervous system of birds. In the present study, we investigated the effects of L-glutamine and L-alanine on feed intak... Different amino acids have been shown to affect feed intake when injected directly into the central nervous system of birds. In the present study, we investigated the effects of L-glutamine and L-alanine on feed intake and the mRNA expression levels of hypothalamic neuropeptides involved in feed intake regulation in broiler chicks. L-Glutamine or L- alanine was intra-cerebroventricularly (ICV) administered to 4-d-old broiler chicks and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of neuropeptide Y (NPY), agouti related protein (AgRP), pro-opiomelanocortin (POMC), melanocortin receptor 4 (MC4R) and corticotropin releasing factor (CRF). Our results showed that ICV administration of L-glutamine (0.55 or 5.5 pmol) significantly increased feed intake up to 2 h post-administration period and the hypothalamic NPY mRNA expression levels, while it markedly decreased hypothalamic POMC and CRF mRNA expression levels. In contrast, ICV administration of L-alanine (4 lamol) significantly decreased feed intake for the first 0.5 h post-administration period, and reduced the hypothalamic AgRP mRNA expression levels, while it remarkablely enhanced the mRNA expression levels of MC4R and CRF. These findings suggested that L-glutamine and L-alanine could act within the hypothalamus to influence feed intake in broiler chicks, and that both orexigenic and anorexigenic neuropeptide genes might contribute directly to these effects. 展开更多
关键词 L-GLUTAMINE L-ALANINE intracerebroventricular (ICV) feed intake hypothalamus
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Possible markers of the Jurassic/Cretaceous boundary in the Mediterranean Tethys:A review and state of art 被引量:3
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作者 Jozef Michalik Daniela Rehkov 《Geoscience Frontiers》 SCIE CAS 2011年第4期475-490,共16页
During the last decades,several integrated studies of Tethyan Jurassic/Cretaceous boundary sections from different countries were published with the objective to indicate problems for the selection of biological,chemi... During the last decades,several integrated studies of Tethyan Jurassic/Cretaceous boundary sections from different countries were published with the objective to indicate problems for the selection of biological,chemical or physical markers suitable for identification of the Jurassic/Cretaceous boundary-the only system boundary within the Phanerozoic still not fixed by GSSP.Drawing the boundary between the Jurassic and Cretaceous systems is a matter of global scale discussions.The problem of proposing possible J/K boundary stratotypes results from lack of a global index fossils, global sea level drop,paleogeographic changes causing development of isolated facies areas,as well as from the effect of Late Cimmerian Orogeny.This contribution summarizes and comments data on J/K boundary interval obtained from several important Tethyan sections and shows still existing problems and discrepancies in its determination. 展开更多
关键词 J/K boundary Interregional correlation Biostratigraphic proxies Calpionellids NANNOFOSSILS
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Geostatistical modelling and mapping of nematode-based soil ecological quality indices in a polluted nature reserve 被引量:3
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作者 Israel O.IKOYI Gerard B.M.HEUVELINK Ron G.M.DE GOEDE 《Pedosphere》 SCIE CAS CSCD 2021年第5期670-682,共13页
Nematodes are indicators of soil quality and soil health.Knowledge of the relationships between nematode-based soil quality indices and environmental properties is beneficial for assessing environmental threats on soi... Nematodes are indicators of soil quality and soil health.Knowledge of the relationships between nematode-based soil quality indices and environmental properties is beneficial for assessing environmental threats on soil biota.This study evaluated the spatial distribution of nematode-based soil quality indices in a 23-ha heavy metal-polluted nature reserve using geostatistical methods.We expected that a selection of abiotic soil properties(pH and moisture,clay,organic matter,cadmium(Cd),and zinc(Zn)contents)could explain a significant portion of the spatial variation of the indices and that regression kriging could more accurately model their spatial distribution than ordinary kriging.A stratified simple random sampling scheme was used to select 80 locations where soil samples were taken to extract nematodes and derive the indices.The area had a distinct gradient in soil properties with Cd and Zn content ranging from 0.07 to 68.9 and 5.3 to 1329 mg kg^(-1),respectively.Linear regression models were fitted to describe the relationships between the indices and soil properties.By also modelling the spatial correlation structure of regression residuals using spherical semivariograms,regression kriging was used to produce maps of the indices.The regression models explained between 21% and 44% of the total original variance in the indices.Soil pH was a significant explanatory variable in almost all cases,while heavy metal conent had a remarkably low effect.In some cases,the regression residuals had spatial structure.Independent validation indicated that in all cases,regression kriging performed slightly better because of having lower values of the root mean square prediction error and a mean prediction error closer to zero than ordinary kriging.This study showed the importance of soil properties in explaining the spatial distribution of biological soil quality indices in ecological risk assessment. 展开更多
关键词 ecological risk assessment heavy metals model validation regression kriging semivariance analysis soil property spatial structure
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Antibacterial mechanism with consequent cytotoxicity of different reinforcements in biodegradable magnesium and zinc alloys: A review 被引量:6
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作者 Chowdhury Ahmed Shahed Faiz Ahmad +4 位作者 Ebru Günister Farhana Mohd Foudzi Saad Ali Khurshid Malik Wan Sharuzi Wan Harun 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第9期3038-3058,共21页
Benefits achieved by the biodegradable magnesium(Mg) and zinc(Zn) implants could be suppressed due to the invasion of infectious microbial, common bacteria, and fungi. Postoperative medications and the antibacterial p... Benefits achieved by the biodegradable magnesium(Mg) and zinc(Zn) implants could be suppressed due to the invasion of infectious microbial, common bacteria, and fungi. Postoperative medications and the antibacterial properties of pure Mg and Zn are insufficient against biofilm and antibiotic-resistant bacteria, bringing osteomyelitis, necrosis, and even death. This study evaluates the antibacterial performance of biodegradable Mg and Zn alloys of different reinforcements, including silver(Ag), copper(Cu), lithium(Li), and gallium(Ga). Copper ions(Cu^(2+)) can eradicate biofilms and antibiotic-resistant bacteria by extracting electrons from the cellular structure. Silver ion(Ag^(+)) kills bacteria by creating bonds with the thiol group. Gallium ion(Ga^(3+)) inhibits ferric ion(Fe^(3+)) absorption, leading to nutrient deficiency and bacterial death. Nanoparticles and reactive oxygen species(ROS) can penetrate bacteria cell walls directly, develop bonds with receptors, and damage nucleotides. Antibacterial action depends on the alkali nature of metal ions and their degradation rate, which often causes cytotoxicity in living cells. Therefore, this review emphasizes the insight into degradation rate, antibacterial mechanism, and their consequent cytotoxicity and observes the correlation between antibacterial performance and oxidation number of metal ions. 展开更多
关键词 Biodegradable materials Biomedical implants Antibacterial mechanism CYTOTOXICITY Reactive oxygen species
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A New Thorny Lacewing (Insecta:Neuroptera:Rhachiberothidae) from the Early Cretaceous Amber of Lebanon 被引量:1
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作者 Julian F.PETRULEVICIUS Dany AZAR André NEL 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第4期828-833,共6页
A new genus and species of Rhachiberothidae, Raptorapax terribilissima gen. et sp. nov. from the Cretaceous amber of Lebanon is described. The new genus is assigned to the subfamily Paraberothinae. The new material co... A new genus and species of Rhachiberothidae, Raptorapax terribilissima gen. et sp. nov. from the Cretaceous amber of Lebanon is described. The new genus is assigned to the subfamily Paraberothinae. The new material confirms the great diversity of the group in the Cretaceous age and its decrease in diversity in recent times. 展开更多
关键词 NEUROPTERA Rhachiberothidae Paraberothinae Neocomian Lower Cretaceous amber Lebanon gen.et sp. nov.
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Effects of “Bioactive” amino acids leucine, glutamate, arginine and tryptophan on feed intake and mRNA expression of relative neuropeptides in broiler chicks 被引量:4
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作者 Songbo Wang Paul Khondowe +8 位作者 Shengfeng Chen Jianjian Yu Gang Shu Xiaotong Zhu Lina Wang Ping Gao Qianyun Xi Yongliang Zhang Qingyan Jiang 《Journal of Animal Science and Biotechnology》 SCIE 2012年第4期199-206,共8页
Feed intake control is vital to ensuring optimal nutrition and achieving full potential for growth and development in poultry. The aim of the present study was to investigate the effects of L-leucine, L-glutamate, L-t... Feed intake control is vital to ensuring optimal nutrition and achieving full potential for growth and development in poultry. The aim of the present study was to investigate the effects of L-leucine, L-glutamate, L-tryptophan and L-arginine on feed intake and the mRNA expression levels of hypothalamic Neuropeptide involved in feed intake regulation in broiler chicks. Leucine, glutamate, tryptophan or arginine was intra-cerebroventricularly (ICV) administrated to 4d-old broiler chicks respectively and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of Neuropeptide Y (NPY), agouti related protein (AgRP), pro-opiomelanocortin (POMC), melanocortin receptor 4 (MC4R) and corticotrophin releasing factor (CRF). Our results showed that ICV administration of L-leucine (0.15 or 1.5 μmol) significantly (P〈0.05) increased feed intake up to 2 h post-administration period and elevated both hypothalamic NPY and AgRP mRNA expression levels. In contrast, ICV administration of L-glutamate (1.6 μmol) significantly (P 〈 0.05) decreased feed intake 0.25, 0.5 and 2 h post-injection, and increased hypothalamic CRF and MC4R mRNA expression levels. Meanwhile, both L-tryptophan (10 or 100 μg) and L-arginine (20 or 200 μg) had no significant effect on feed intake. These findings suggested that L-leucine and L-glutamate could act within the hypothalamus to influence food intake, and that both orexigenic and anorexigenic Neuropeptide genes might contribute directly to these effects. 展开更多
关键词 Broiler chicks Feed intake HYPOTHALAMUS Intracerebroventricular (ICY) L-LEUCINE L-GLUTAMATE
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Genetic differentiation in two widespread, open-forest bird species of Southeast Asia (Copsychus saularis and Megalaima haemacephala): Insights from ecological niche modeling 被引量:2
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作者 Haw Chuan LIM Fasheng ZOU Frederick H. SHELDON 《Current Zoology》 SCIE CAS CSCD 2015年第5期922-934,共13页
Ecological niche modeling has emerged as an useful tool in the investigation of the phylogeographic histories of species or communities in a region. The high biodiversity (oftentimes cryptic), and complex geography ... Ecological niche modeling has emerged as an useful tool in the investigation of the phylogeographic histories of species or communities in a region. The high biodiversity (oftentimes cryptic), and complex geography and geological history of Southeast Asia particularly call for multipronged approaches in phylogeographic investigations. Past studies have focused on taxa that are associated with lowland rainforests, which is the dominant natural vegetation type. Here, we combine published phylogenetic data, ecological niche modeling and paleo-climate models to reveal potential drivers of divergence in two open-forest bird species, the oriental magpie-robin Copsychus saularis and Coppersmith barbet Megalaima haemacephala. In spite of broad overlap in current distributions, there are subtle differences in their climatic niches, which result in different responses to past climatic changes. For C saularis, both Last Glacial Maximum climate models indicated that the entire Sundaland was climati- cally suitable, while phylogenetic analyses found divergent eastern and western Sundaland lineages. We thus postulate that this genetic divergence was a result of past separations of coastal habitats into eastern and western portions due to the emergence of Sunda shelf as sea-level fell. The current separation of morphological subspecies in Borneo is maintained by low climatic suitability (high annual rainfall) in certain regions. The extirpation of M. haemacephala from Borneo and southern Malay Peninsula might have been driven by unsuitable conditions (high temperature seasonality) in central Sundaland and/or the lack of open woodlands. Our study shows that ecological niche modeling adds a powerful dimension to our attempt to understand lineage evolution in space [Current Zoology 61 (5): 922-934, 2015]. 展开更多
关键词 Barbet Indo-Burma Malay Archipelago Magpie-robin PHYLOGEOGRAPHY Species distribution modeling
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Assessment of Reusing Ferrochrome Slag Wastes in Mortar as SCMs 被引量:1
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作者 IŞIL Sanrı Karapınar HASAN Biricik 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第6期1043-1052,共10页
The demand for alternative cementitious materials is on the rise,as the cement causes huge energy consumption and produces greenhouse gas emission.Additionally,there is economic potential for the construction industry... The demand for alternative cementitious materials is on the rise,as the cement causes huge energy consumption and produces greenhouse gas emission.Additionally,there is economic potential for the construction industry to reuse wastes as supplementary building materials.The purpose of this study is to evaluate the potential of utilizing ferrochrome slag wastes in mortar as supplementary cementitious materials (SCMs),thereby achieving this double-sided goal.Thus,the mechanical and physical properties of ferrochrome slag wastes were investigated to be used as admixtures in concrete production.Three different cement mortar specimens were prepared by replacing cement with ferrochrome slag in ratios of 0,30%,and 60% by mass and flexural and compressive strengths of the specimens were determined at the ages of 7,28,56,90,and 180 days.Also,the effects of the ferrochrome slag replacement ratio on workability,setting time and volume expansion were revealed.Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were also investigated to study the microstructural properties of the specimens containing ferrochrome slag.Based on the results,it is concluded that ferrochrome slag wastes have pozzolanic activity,therefore reusing them as SCMs in the cement and concrete industry is convenient. 展开更多
关键词 RECYCLING reuse of materials ferrochrome slags pozzolanic activity physical and mechanical properties concrete technology
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Foraging ecology and occurrence of 7 sympatric babbler species (Timaliidae) in the lowland rainforest of Borneo and peninsular Malaysia 被引量:2
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作者 Alison R. STYRING Roslina RAGAI +1 位作者 Mohamed ZAKARIA Frederick H. SHELDON 《Current Zoology》 SCIE CAS CSCD 2016年第4期345-355,共11页
Understanding foraging strategies of birds is essential to understanding mechanisms of their community assembly. To provide such information on a key Southeast Asian rainforest family, the babblers (Timaliidae), we ... Understanding foraging strategies of birds is essential to understanding mechanisms of their community assembly. To provide such information on a key Southeast Asian rainforest family, the babblers (Timaliidae), we evaluated foraging behavior and abundance in 7 morphologically and behaviorally similar sympatric species (Cyanoderma erythropterum, C. rufifrons, Stachyris maculata, S. nigricollis, S. poliocephala, Macronus ptilosus, and Mixornis gularis) in 5 habitats defined by structural complexity: (1) continuous native rainforest, (2) logged native rainforest fragments, (3) mature industrial tree plantation, (4) young industrial plantation, and (5) oil palm plantation. Enough data were obtained to compare abundance in all 7 species and foraging behavior in 5. All species were common in forest fragments and mature industrial tree plantations and less so in continuous rainforest and young industrial plantations; only M. gularis occurred in oil palm. In terms of foraging, M. gularis was the greatest generalist; C. rufifrons foraged mainly on live leaves in the forest midstory; and S. maculata, C. eryth- ropterum, and M. ptilosus foraged mainly on dead leaves suspended in understory vegetation at sig- nificantly different heights. The dead-leaf substrate depends on a rich supply of falling leaves and ex- tensive understory structure, conditions most common in native forest and old industrial plantations, and less so in mature forest, young plantations, and oil palm. Because of the importance of foraging data to understanding and managing biodiversity, we encourage the development of foraging fields in eBird (ebird.org), so that birdwatchers may help collect these relatively rare data. 展开更多
关键词 BRUNEI dead leaves logged forest plantation SABAH Sarawak.
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