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Novel Investigation of Stochastic Fractional Differential Equations Measles Model via the White Noise and Global Derivative Operator Depending on Mittag-Leffler Kernel 被引量:1
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作者 Saima Rashid Fahd Jarad 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2289-2327,共39页
Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this p... Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this paper,we constructed a stochastic fractional framework of measles spreading mechanisms with dual medication immunization considering the exponential decay and Mittag-Leffler kernels.In this approach,the overall population was separated into five cohorts.Furthermore,the descriptive behavior of the system was investigated,including prerequisites for the positivity of solutions,invariant domain of the solution,presence and stability of equilibrium points,and sensitivity analysis.We included a stochastic element in every cohort and employed linear growth and Lipschitz criteria to show the existence and uniqueness of solutions.Several numerical simulations for various fractional orders and randomization intensities are illustrated. 展开更多
关键词 Measles epidemic model Atangana-Baleanu Caputo-Fabrizio differential operators existence and uniqueness qualitative analysis Newton interpolating polynomial
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Understanding the oxidation chemistry of Ti_(3)C_(2)T_(x)(MXene)sheets and their catalytic performances 被引量:1
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作者 Suvdanchimeg Sunderiya Selengesuren Suragtkhuu +9 位作者 Solongo Purevdorj Tumentsereg Ochirkhuyag Munkhjargal Bat-Erdene Purevlkham Myagmarsereejid Ashley DSlattery Abdulaziz SRBati Joseph GShapter Dorj Odkhuu Sarangerel Davaasambuu Munkhbayar Batmunkh 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期437-445,I0010,共10页
Transition metal carbides and nitrides(MXenes)nanosheets are attractive two-dimensional(2D)materials,but they suffer from oxidation/degradation issues during storage and/or applications due to their sensitivity to wat... Transition metal carbides and nitrides(MXenes)nanosheets are attractive two-dimensional(2D)materials,but they suffer from oxidation/degradation issues during storage and/or applications due to their sensitivity to water and oxygen.Despite the great research progress,the exact oxidation kinetics of Ti_(3)C_(2)T_(x)(MXene)and their final products after oxidation are not fully understood.Herein,we systematically tracked the oxidation process of few-layer Ti_(3)C_(2)T_(x) nanosheets in an aqueous solution at room temperature over several weeks.We also studied the oxidation effects on the electrocatalytic properties of Ti_(3)C_(2)T_(x) for hydrogen evolution reaction and found that the overpotential to achieve a current density of 10 mA cm^(-2)increases from 0.435 to 0.877 V after three weeks of degradation,followed by improvement to stabilized values of around 0.40 V after eight weeks.These results suggest that severely oxidized MXene could be a promising candidate for designing efficient catalysts.According to our detailed experimental characterization and theoretical calculations,unlike previous studies,black titanium oxide is formed as the final product in addition to white Ti(IV)oxide and disordered carbons after the complete oxidation of Ti_(3)C_(2)T_(x).This work presents significant advancements in better understanding of 2D Ti_(3)C_(2)T_(x)(MXene)oxidation and enhances the prospects of this material for various applications. 展开更多
关键词 2D materials MXene Chemical degradation CATALYSIS Hydrogen evolution reaction
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The Impacts of Flood and Local Communities’ Coping Strategies along the River Gambia
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作者 Edward Mendy Sêmihinva Akpavi +1 位作者 Sidat Yaffa Alpha Kargbo 《American Journal of Climate Change》 2024年第3期522-542,共21页
Flood disasters as Climate change hazards are common in developing countries, particularly in communities along the river Gambia. Local communities, for instance, had their local coping strategies that enabled them to... Flood disasters as Climate change hazards are common in developing countries, particularly in communities along the river Gambia. Local communities, for instance, had their local coping strategies that enabled them to stay in their communities even amid these ordeals, and climate change disaster threats. This work strives to understand flood impacts and the local peoples’ adaptation or coping strategies along the River Gambia basin. A community-based cross-sectional research study of 422 research participants of which 294 are males (69.7%) and females 128 (30.3%), and a focus group discussion of 10 groups which comprised 5 female groups and 5 male groups respectively found that 98.6% of the households experienced floods in their community, and 70.6% experienced flood in their houses, 2.1% have impending flood information and 88.4% do not know evacuation centres. The majority of the households had some local coping strategies, but they acknowledged their insufficient effectiveness. The result also shows that the impact of floods on farmlands, roads, buildings, and livestock was greatly felt. Coping strategies such as sandbags, raised elevations, contour bonds, dikes, and buildings on highlands were all found to be common mechanisms the local people used. The study opines that floods affect communities, but the effects vary depending on individual assets. 展开更多
关键词 Coping Strategies DISASTER Flood Impact Climate Change Hazard Local Communities
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The Transport and Persistence of Escherichia coli in Leachate from Poultry Litter Amended Soils
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作者 Lorra Belle Hill 《Open Journal of Soil Science》 2024年第4期269-282,共14页
Fecal coliform bacteria such as Escherichia coli (E. coli) are one of the main sources of groundwater pollution. An assessment of the transport and Persistence of E. coli in poultry litter amended Decatur silty Clay s... Fecal coliform bacteria such as Escherichia coli (E. coli) are one of the main sources of groundwater pollution. An assessment of the transport and Persistence of E. coli in poultry litter amended Decatur silty Clay soil and Hartsells Sandy soil was conducted using soil columns and simulated groundwater leaching. Enumeration of initial E. coli was determined to range from 2.851 × 10<sup>3</sup> to 3.044 × 10<sup>3</sup> CFU per gram of soil. These results have been used in a batch study to determine the persistence rate of E. coli in Decatur silty Clay soil and Hartsells Sandy soil. Results prove that E. coli survival growth rate increases for clay soil later than and at a higher rate than sandy soil. The column study has determined that E. coli was transported at a rate of 3.7 × 10<sup>6</sup><sup> </sup>CFU for Decatur silty loam and 6.3 × 10<sup>6</sup><sup> </sup>CFU for Hartsells sandy per gram of soil. Further, linear regression analysis predictions show higher porosity and soil moisture content affect transport, and Hartsells sandy soil has higher transport of E. coli due to its higher porosity and lower volumetric water content. 展开更多
关键词 TRANSPORT LEACHATE PERSISTENCE Poultry Litter E. coli
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Quantitative Analysis of the Effectiveness of Antigen-and Polymerase Chain Reaction-Based Combination Strategies for Containing COVID-19 Transmission in a Simulated Community
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作者 Qiangru Huang Yanxia Sun +6 位作者 Mengmeng Jia Ting Zhang Fangyuan Chen Mingyue Jiang Qing Wang Luzhao Feng Weizhong Yang 《Engineering》 SCIE EI CAS CSCD 2023年第9期234-242,共9页
The number of coronavirus disease 2019(COVID-19)cases continues to surge,overwhelming healthcare systems and causing excess mortality in many countries.Testing of infectious populations remains a key strategy to conta... The number of coronavirus disease 2019(COVID-19)cases continues to surge,overwhelming healthcare systems and causing excess mortality in many countries.Testing of infectious populations remains a key strategy to contain the COVID-19 outbreak,delay the exponential spread of the disease,and flatten the epidemic curve.Using the Omicron variant outbreak as a background,this study aimed to evaluate the effectiveness of testing strategies with different test combinations and frequencies,analyze the factors associated with testing effectiveness,and optimize testing strategies based on these influencing factors.We developed a stochastic,agent-based,discrete-time susceptible–latent–infectious–recovered model simulating a community to estimate the association between three levels of testing strategies and COVID-19 transmission.Antigen testing and its combination strategies were more efficient than polymerase chain reaction(PCR)-related strategies.Antigen testing also showed better performance in reducing the demand for hospital beds and intensive care unit beds.The delay in the turnaround time of test results had a more significant impact on the efficiency of the testing strategy compared to the detection limit of viral load and detection-related contacts.The main advantage of antigen testing strategies is the short turnaround time,which is also a critical factor to be optimized to improve PCR strategies.After modifying the turnaround time,the strategies with less frequent testing were comparable to daily testing.The choice of testing strategy requires consideration of containment goals,test efficacy,community prevalence,and economic factors.This study provides evidence for the selection and optimization of testing strategies in the post-pandemic era and provides guidance for optimizing healthcare resources. 展开更多
关键词 COVID-19 Antigen testing PCR testing Testing strategies
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Characteristics and C-E Translation Methods of the Four-Character Frame in the Subtitles of the Documentary Daming Palace
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作者 Junqi Jiang 《Open Journal of Applied Sciences》 CAS 2023年第3期424-430,共7页
This paper studies the four-character frame in the subtitle of the documentary Daming Palace, aiming to provide a reference for the translation of the documentary four-character case as well as better spread Chinese c... This paper studies the four-character frame in the subtitle of the documentary Daming Palace, aiming to provide a reference for the translation of the documentary four-character case as well as better spread Chinese culture. By analyzing, researching and summarizing the subtitle of Daming Palace and reading a lot of literature, the author has found that in Daming Palace the four-character frame is characterized by the use of the absolute four-character frames and the recurrence of some four-character frames, and that C-E translation methods of the four-character frame are mainly literal translation, free translation, provincial translation and concise translation. 展开更多
关键词 Documentary Subtitles Four-Character Frame English Translation
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Characterizations of semihoops based on derivations
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作者 WANG Mei ZHANG Xiao-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期291-310,共20页
In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of them.Then,we prove that every Heyting algebra is isomorphic to the algebra of all multipli... In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of them.Then,we prove that every Heyting algebra is isomorphic to the algebra of all multiplicative derivations and show that every Boolean algebra is isomorphic to the algebra of all implicative derivations.Finally,we show that the sets of multiplicative and implicative derivations on bounded regular idempotent semihoops are in oneto-one correspondence. 展开更多
关键词 (prelinear)semihoop DERIVATION Heyting algebra Galois connection
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Hydroxychloroquine and a low antiresorptive activity bisphosphonate conjugate prevent and reverse ovariectomy-induced bone loss in mice through dual antiresorptive and anabolic effects
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作者 Zhenqiang Yao Akram Ayoub +8 位作者 Venkatesan Srinivasan Jun Wu Churou Tang Rong Duan Aleksa Milosavljevic Lianping Xing Frank H.Ebetino Alison J.Frontier Brendan F.Boyce 《Bone Research》 SCIE CAS CSCD 2024年第3期734-744,共11页
Osteoporosis remains incurable.The most widely used antiresorptive agents,bisphosphonates(BPs),also inhibit bone formation,while the anabolic agent,teriparatide,does not inhibit bone resorption,and thus they have limi... Osteoporosis remains incurable.The most widely used antiresorptive agents,bisphosphonates(BPs),also inhibit bone formation,while the anabolic agent,teriparatide,does not inhibit bone resorption,and thus they have limited efficacy in preventing osteoporotic fractures and cause some side effects. 展开更多
关键词 res CONJUGATE phosphonate
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Scenario-Based Assessment of the Water-Energy-Food Nexus in Kuwait: Insights for Effective Resource Management
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作者 Amani Al-Adwani Ali Karnib +1 位作者 Alaa Elsadek Waleed Al-Zubari 《Computational Water, Energy, and Environmental Engineering》 2024年第1期38-57,共20页
The interdependency among water, food, and energy (WEF) in the GCC countries is strongly and closely interlinked, and is intensifying as demand for resources increases with population growth and changing consumption p... The interdependency among water, food, and energy (WEF) in the GCC countries is strongly and closely interlinked, and is intensifying as demand for resources increases with population growth and changing consumption patterns, and are expected to be further compounded by the impacts of climate change. Therefore, integrated management of the three sectors is crucial to reduce trade-offs and build synergies among them. This paper presents a comprehensive framework to assess the WEF nexus in Kuwait as a representative case for the GCC countries. The framework consists of three main steps: 1) evaluating the influence of socio-economic development and climate change on water, energy, and food resources;2) generating scenario-based projections;and 3) conducting an extensive quantitative nexus analysis. The WEF interlinkages in Kuwait are modelled quantitatively using the Q-Nexus model, and current critical interdependencies are evaluated. Then, various WEF-Nexus scenarios were conducted for the year 2035 to explore the effects of management interventions in one sector on the other two sectors. The main findings are that per capita municipal water consumption is a major influencer on the WEF-nexus due to the heavy reliance on thermal desalination in municipal water supply in Kuwait, which is attributed to its energy intensity, financial cost, GHGs emissions, and environmental impacts on the marine and air environments. To reduce WEF trade-offs, mitigate risks, and build synergies among the three sectors, it is important to shift the current policy focus on supply-side management approach to the demand-side management and efficiency approaches. 展开更多
关键词 Climate Change Socio-Economic Development Municipal Water Consumption Agricultural Water Consumption Renewable Energy Desalination Technology
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Spatial and temporal variability in vegetation cover of Mongolia and its implications 被引量:4
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作者 Sumiya VANDANDORJ Batdelger GANTSETSEG Bazartseren BOLDGIV 《Journal of Arid Land》 SCIE CSCD 2015年第4期450-461,共12页
In this paper, we attempted to determine the most stable or unstable regions of vegetation cover in Mongolia and their spatio-temporal dynamics using Terra/MODIS Normalized Difference Vegetation Index (NDVI) dataset... In this paper, we attempted to determine the most stable or unstable regions of vegetation cover in Mongolia and their spatio-temporal dynamics using Terra/MODIS Normalized Difference Vegetation Index (NDVI) dataset, which had a 250-m spatial resolution and comprised 6 periods of 16-day composited temporal resolution data (from 10 June to 13 September) for summer seasons from 2000 to 2012. We also used precipitation data as well as biomass data from 12 meteorological stations located in 4 largest natural zones of Mongolia. Our study showed that taiga and forest steppe zones had relatively stable vegetation cover because of forest characteristics and relatively high precipitation. The highest coefficient of variation (CV) of vegetation cover occurred frequently in the steppe and desert steppe zones, mainly depending on variation of precipitation. Our results showed that spatial and temporal variability in vegetation cover (NDVI or plant biomass) of Mongolia was highly dependent on the amount, distribution and CV of precipitation. This suggests that the lowest inter-annual CV of NDVI can occur dur- ing wet periods of growing season or in high precipitation regions, while the highest inter-annual CV of NDVI can occur during dry periods and in low precipitation regions. Although the desert zone received less precipitation than other natural zones of the country, it had relatively low variation compared to the steppe and desert steppe, which could be attributed to the very sparse vegetation in the desert. 展开更多
关键词 vegetation cover MODIS NDVI natural zones seasonal dynamics STABILITY Mongolia
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Internal Microanatomy and Zoological Affinity of the Early Cambrian Olivooides 被引量:5
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作者 Han Jian LI Guoxiang +10 位作者 KUBOTA Shin OU Qiang TOSHINO Sho WANG Xing YANG Xiaoguang UESUGI Kentaro MASATO Hoshino SASAKI Osamu KANO Harumasa SATO Tomohiko KOMIYA Tsuyoshi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期38-65,共28页
The early Cambrian pentamerous microfossil Olivooides/Punctatus in South China, which is characterized by a diagnostic stellate tubular apex, has been well-known for its almost complete development sequence that can b... The early Cambrian pentamerous microfossil Olivooides/Punctatus in South China, which is characterized by a diagnostic stellate tubular apex, has been well-known for its almost complete development sequence that can be confidently traced from embryos and hatched juveniles, to conical adults. However, its zoological affinity remains highly controversial. Here we describe the internal microanatomic structures of the soft-body inside the peridermal theca of Olivooides multisulcatus Qian, 1977, including interradial pairs of tentacles, adradial and perradial frenula, perradial oral marginal lappets and twins of perradial gastric saccule-like humps as well as a circular velarium with striated coronal muscles. Particularly, one specimen shows bifurcated velarial canals along the bell aperture. Both the components of the soft-body and the external theca (or cyst) are arranged in perfect pentaradial symmetry. These characteristics are more compatible with those of living cubomedusans and co-occurring Cambrian athecate embryonic cubozoans. Concerning the presence of peridermal theca, Olivooides most likely represents an extinct thecate stem-group cubomedusae but devoid of both perradial eyes and specialized pedalia. The well-grown soft body inside the peridermal tube displays a set of mixed features of both polyp and medusa. 展开更多
关键词 Embryos PERIDERM CNIDARIANS cubozoan early Cambrian Kuanchuanpu Formation
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Redox history of the Three Gorges region during the Ediacaran and Early Cambrian as indicated by the Fe isotope 被引量:2
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作者 Yusuke Sawaki Miyuki Tahata +3 位作者 Tsuyoshi Komiya Takafumi Hirata Jian Han Degan Shu 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第1期155-172,共18页
The Ediacaran-Cambrian transition is characterized by numerous events such as the emergence of large multi-cellular metazoans and surface environmental disturbances.Based on geological evidence,it has been proposed th... The Ediacaran-Cambrian transition is characterized by numerous events such as the emergence of large multi-cellular metazoans and surface environmental disturbances.Based on geological evidence,it has been proposed that this transition coincided with the increase in the atmospheric oxygen level that was key to the evolution of life.Even though ancient redox conditions can be inferred from the composition of sedimentary iron mineral species,this method is not necessarily applicable to all rocks.In the Earth system,the cycling of iron is of considerable interest owing to its sensitivity to redox conditions.Information regarding the paleo-oceanic iron cycle is revealed in the iron isotopic composition of ironbearing minerals.Unfortunately,only limited iron isotopic data exists for Ediacaran-to Cambrianperiod oceans.To circumvent this deficiency,we drilled a fossiliferous Ediacaran to Early Cambrian sedimentary succession in the Three Gorges region,South China.We analyzed the iron isotope ratios(δ^(56/54)Fe)of pyrite grains in the drill cores using laser ablation multi collector inductively coupled plasma mass spectrometry.The results demonstrate large variations inδ^(56/54)Fe,from-1.6 to 1.6‰,and positive iron isotope ratios are observed in many successions.The presence of positiveδ^(56/54)Fe in pyrite indicates that the ferrous iron in the seawater was partially oxidized,suggesting that seawater at Three Gorges was ferruginous during the Ediacaran and Early Cambrian periods.However,aggregated pyrite grains in organic carbon-rich black shales at Member 4 of the Doushantuo Formation and the base of the Shuijingtuo Formation yield near-zeroδ^(56/54)Fe values;this suggests that the ocean was transiently dominated by sulfidic conditions during these periods.Notably negativeδ^(56/54)Fe values,lower than-1‰,can be interpreted as a signature of DIR.The DIR also might contribute in part to the re-mineralization of organic matter during the largest negative carbon isotope anomaly in the Ediacaran. 展开更多
关键词 δ56/54Fe PYRITE EDIACARAN CAMBRIAN Three Gorges
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Modulatory Effect of Motivation on the Association of Trait Anxiety and Cognitive Performance: A Pupillometric Study 被引量:1
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作者 Takatoshi Hoshino Yoshihiko Tanno 《Journal of Behavioral and Brain Science》 2017年第7期273-286,共14页
The attentional control theory (ACT) proposes that trait anxiety disrupts functional efficiency of executive control of attention relating to working memory system such as shifting. ACT also emphasizes the modulatory ... The attentional control theory (ACT) proposes that trait anxiety disrupts functional efficiency of executive control of attention relating to working memory system such as shifting. ACT also emphasizes the modulatory role of motivation in anxiety on cognitive task performance. The present study investigated the association of trait anxiety-related inefficiencies in attentional shift and working memory performance in conjunction with the level of motivation. A variation of complex span paradigm is designed to systematically manipulate the time constraint on shifting attentional focus back and forth between working memory contents and processing task was used in this study. In the experiment, participants high and low in trait anxiety were allocated either high or low motivation induction conditions, and performed a series of complex span tasks. They also completed a state anxiety measure before and after the experimental task. Motivational states were assessed by the pupil dilation, which is known to reflect the amount of cognitive effort invested on the task at hand. Results showed that, only in low motivation condition, high trait-anxious individuals exhibited greater difficulty, relative to those low in trait anxiety, in maintaining working memory contents as the task demand increased. State anxiety showed no relation to working memory performance regardless of the level of motivation and task demands. Pupillary responses revealed that, in high motivational state, high trait-anxious individuals invested more effort than those low in trait anxiety when the task demand was low, F(1, 132) = 6.65, p = 0.0110, to moderate, F(1, 132) = 8.441, p = 0.00043. In accordance with ACT, these findings suggest that motivation can modulate the association between trait anxiety and cognitive performance along with the levels of task demand. Clinical implication is briefly discussed. 展开更多
关键词 TRAIT ANXIETY MOTIVATION Working Memory Attentional Control Theory (ACT) PUPILLOMETRY
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Neurobehavioral and Hemodynamic Evaluation of Cognitive Shifting in Children with Autism Spectrum Disorder 被引量:1
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作者 Akira Yasumura Naomi Kokubo +5 位作者 Hisako Yamamoto Yukiko Yasumura Yusuke Moriguchi Eiji Nakagawa Masumi Inagaki Kazuo Hiraki 《Journal of Behavioral and Brain Science》 2012年第4期463-470,共8页
The restrictive, stereotyped behavior in autism spectrum disorder (ASD) is considered to be related to deficits in execu- tive function. In particular, cognitive shifting in executive function is deeply related to ste... The restrictive, stereotyped behavior in autism spectrum disorder (ASD) is considered to be related to deficits in execu- tive function. In particular, cognitive shifting in executive function is deeply related to stereotyped behavior in ASD. Previous investigations have clarified that the lateral prefrontal cortex is involved in cognitive shifting when flexible changes in attention were needed. However, a few studies have revealed a direct association between cognitive shifting tasks and lateral prefrontal cortex activity in children with ASD. We examined cognitive shifting in 7- to 12-year-old children with ASD and typically developing children using the dimensional change card sort task. In addition, using near-infrared spectroscopy, we examined prefrontal brain activity in conjunction with cognitive shifting. The autistic children provided fewer correct answers and slower reaction times in the task than typically developing children. Fur- thermore, the autistic children displayed a decline in right lateral prefrontal cortex activity during the task compared with typically developing children. In addition, a negative correlation was observed between the severity of autism and brain activity during the task. These results suggest that the activity and physiological indices used in this study may be useful for identifying the symptoms of ASD and discriminating ASD from other disabilities. 展开更多
关键词 Autism SPECTRUM DISORDER Executive FUNCTION COGNITIVE SHIFTING Frontal Lobe FUNCTION Near-Infrared Spectroscopy
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Growth, Duplication and Lateral Mutual Compressive Deformation of Akouemma hemisphaeria on the Seafloor of Okondja Basin at 2.2 Ga (Gabon) 被引量:1
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作者 Ambroise Edou-Minko Mathieu Moussavou +13 位作者 Tomohiko Sato Yusuke Sawaki Simplice Ndong Ondo Richard Maire Guillaume Fleury Michel Mbina Mounguengui Anders Kaestner Richard Ortega Stéphane Roudeau Asuncion Carmona Makaya Mvoubou Benjamin Musavu Moussavou Osamu Sasaki Shigenori Maruyama 《International Journal of Geosciences》 2017年第9期1172-1191,共20页
A colony of macro-fossils Akouemma hemisphaeria has been described in the Paleoproterozoic sedimentary basin of Okondja, Gabon. These fossils are classified into two groups according to their spheroidal or elongated f... A colony of macro-fossils Akouemma hemisphaeria has been described in the Paleoproterozoic sedimentary basin of Okondja, Gabon. These fossils are classified into two groups according to their spheroidal or elongated forms. The spheroidal shapes are similar, have a tripartite structure with two hemispheres and a median disc and gradually pass to the elongated forms. These elongated forms have a pronounced bipartite tendency to two “hemispheres” separated by a median surface, and often have several ovoid “pieces” attached. The elongated specimens show both lateral growth marks and signs of fission. Growth marks are characterized by unidirectional homogeneous side elongations and lateral bud-like protuberances. The signs of fission are marked by circular furrows perpendicular to the direction of elongation, called “constriction furrows” with varying depths depending on the degree of fission of the specimen and internal vertical “division planes”. All of these ovoid and elongated specimens have undergone significant initial deformations due mainly to mutual lateral compressions in tabular beds. The Akouemma hemisphaeria macro-organisms, which were primitive probably sessile organisms, lived on the seafloor. They provide the oldest known record of macro-organisms on Earth having vegetative growth and asexual reproduction by budding, lateral elongation and fission. Their mutual lateral deformations would result from their growth. 展开更多
关键词 PALEOPROTEROZOIC Francevillian Group Okondja BASIN Akouemma hemisphaeria GROWTH DUPLICATION
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Quasinormal Modes of a Noncommutative-Geometry-Inspired Schwarzschild Black Hole: Gravitational, Electromagnetic and Massless Dirac Perturbations
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作者 Jun Liang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期15-19,共5页
In our previous work [Chin. Phys. Lett. 35(2018) 010410], the quasinormal modes of massless scalar field perturbation in a noncommutative-geometry-inspired Schwarzschild black hole spacetime are studied using the th... In our previous work [Chin. Phys. Lett. 35(2018) 010410], the quasinormal modes of massless scalar field perturbation in a noncommutative-geometry-inspired Schwarzschild black hole spacetime are studied using the third-order Wentzel–Kramers–Brillouin approximative approach. In this study, we extend the work to the cases of gravitational, electromagnetic and massless Dirac perturbations. The result further confirms that the noncommutative parameter plays an important role for the quasinormal frequencies. 展开更多
关键词 NC Quasinormal Modes of a Noncommutative-Geometry-Inspired Schwarzschild Black Hole Electromagnetic and Massless Dirac Perturbations GRAVITATIONAL
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Geoecological parameters indicate discrepancies between potential and actual forest area in the forest-steppe of Central Mongolia
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作者 Michael Klinge Choimaa Dulamsuren +4 位作者 Florian Schneider Stefan Erasmi Uudus Bayarsaikhan Daniela Sauer Markus Hauck 《Forest Ecosystems》 SCIE CSCD 2021年第4期735-754,共20页
Background:Forest distribution in the forest-steppe of Mongolia depends on relief,permafrost,and climate,and is highly sensitive to climate change and anthropogenic disturbance.Forest fires and logging decreased the f... Background:Forest distribution in the forest-steppe of Mongolia depends on relief,permafrost,and climate,and is highly sensitive to climate change and anthropogenic disturbance.Forest fires and logging decreased the forest area in the forest-steppe of Mongolia.The intention of this study was to identify the geoecological parameters that control forest distribution and living-tree biomass in this semi-arid environment.Based on these parameters,we aimed to delineate the area that forest might potentially occupy and to analyse the spatial patterns of actual and potential tree biomass.Methods:We used a combination of various geographic methods in conjunction with statistical analyses to identify the key parameters controlling forest distribution.In several field campaigns,we mapped tree biomass and ecological parameters in a study area within the Tarvagatai Nuruu National Park(central Mongolia).Forest areas,topographic parameters and vegetation indices were obtained from remote sensing data.Significant correlations between forest distribution and living-tree biomass on one hand,and topographic parameters,climate data,and environmental conditions on the other hand,were used to delineate the area of potential forest distribution and to estimate total living-tree biomass for this area.Results:Presence of forest on slopes was controlled by the factors elevation,aspect,slope,mean annual precipitation,and mean growing-season temperature.Combining these factors allowed for estimation of potential forest area but was less suitable for tree-biomass delineation.No significant differences in mean living-tree biomass existed between sites exposed to different local conditions with respect to forest fire,exploitation,and soil properties.Tree biomass was reduced at forest edges(defined as 30m wide belt),in small fragmented and in large forest stands.Tree biomass in the study area was 20×10^(9) g(1,086 km^(2) forest area),whereas the potential tree biomass would reach up to 65×10^(9) g(>3168 km^(2)).Conclusions:The obtained projection suggests that the potential forest area and tree biomass under the present climatic and geoecological conditions is three times that of the present forest area and biomass.Forest fires,which mostly affected large forest stands in the upper mountains,destroyed 43% of the forest area and 45% of the livingtree biomass in the study area over the period 1986-2017. 展开更多
关键词 BIOMASS Fire Forest-steppe Geoecological factors Mongolia PERMAFROST
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Mssbauer and XRD characterization of contaminated sediments by coal mining drainage in Neath Canal, South Wales, UK
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作者 Guodong ZHENG Akihito Kuno +5 位作者 Talib Abdulameer Mahdi David J. Evans Masaaki Miyahara Yoshio Takahashi Motoyuki Matsuo Hiroshi Shimizu 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期137-138,共2页
关键词 矿山酸性排水 氧化铁 沉积物 重金属 环境污染
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Morphodynamic development of the Terkhiin Tsagaan Lake Depression,Central Mongolia:Implications for the relationships of Faulting,Volcanic Activity,and Lake Depression Formation
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作者 Altanbold ENKHBOLD Ulambadrakh KHUKHUUDEI +4 位作者 Timothy KUSKY CHUN Xi Gansukh YADAMSUREN Byambabayar GANBOLD Tuvshin GERELMAA 《Journal of Mountain Science》 SCIE CSCD 2022年第9期2451-2468,共18页
Data on the origin and morphology of lake depressions caused by volcanism are scarce in Mongolia.Previous studies focused on climate change patterns based on Terkhiin Tsagaan Lake sediment.We present a result of exist... Data on the origin and morphology of lake depressions caused by volcanism are scarce in Mongolia.Previous studies focused on climate change patterns based on Terkhiin Tsagaan Lake sediment.We present a result of existing reconstructions of lake depression development and changes in the hydrology system during the Khorgo volcanic activation and the Holocene environmental change.A depression of the Terkhiin Tsagaan Lake is formed by a lava flow barrier from the Khorgo volcano.However,the Khorgo volcanic eruption and the lake depression that could shape a large lake have arisen instead from a fault.The morphometric analysis and field measurements indicate that the derivation of the Terkhiin Tsagaan Lake depression and Khorgo volcano may have evolved from movement on a sinistral strike-slip fault,which is about 70 km long.The southern mountains and rivers were displaced from northwest to southeast along the Terkh Fault.The offset along Terkh Fault is 4.02-5.28 km in the depression of the Terkhiin Tsagaan Lake.After movement,a wide valley of the Terkh River developed in the present landscape.The active Khorgo Volcano formed along the Khorgo Fault.The Terkhiin Tsagaan Lake is formed by blocked water from the PaleoTerkh River after lava damming from the Khorgo Volcano.The initial paleo-lake area was about 195.7km^(2),which was three times larger than the modern lake.The current water volume of the Terkhiin Tsagaan Lake is 0.351 km^(3) while the volume of the paleo-lake was 2.248 km^(3).Based on this volume indicator the paleo-lake was 6.4 times larger than the current lake.Overflowing water from the lake depression formed the Suman River by a drying canyon through the lava plateau,but the canyon is along the Terkh Fault.Changes in the water volume of Terkhiin Tsagaan Lake and erosion of Suman River canyon are inversely related to each other.We present the morphometric relationships between the lava plateau of Khorgo Volcano and development of Terkhiin Tsagaan Lake depression. 展开更多
关键词 Khangay Mountain Khorgo Volcano Lava plateau Sinistral strike-slip fault Terkhiin Tsagaan Lake Morphometric analysis
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Design and Development of Garment Fabric Database Management System
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作者 DU Jianxia LIU Zhengdong GENG Zengmin 《Journal of Donghua University(English Edition)》 CAS 2022年第4期392-399,共8页
The main performance characteristics of garment fabric are analyzed and extracted,which include physical characteristics,appearance characteristics and subjective evaluation characteristics.A calculating model of fab... The main performance characteristics of garment fabric are analyzed and extracted,which include physical characteristics,appearance characteristics and subjective evaluation characteristics.A calculating model of fabric’s subjective evaluation is provided,which can be adjusted as the data increasing.The database system of garment fabric is analyzed,and then function design,concept design and logic design are carried out.The user interface(UI)design of garment fabric database system is described.The system can not only serve the fabric management and customization of garment enterprises,but also serve the teaching work of colleges and universities,because it is rich in information and convenient.It is of great significance to digital construction in the clothing field. 展开更多
关键词 fabric physical characteristic subjective evaluation model of fabric fabric database design concept design logic design
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