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Research on Anti-Fluctuation Control of Winding Tension System Based on Feedforward Compensation
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作者 Yujie Duan Jianguo Liang +4 位作者 Jianglin Liu Haifeng Gao Yinhui Li Jinzhu Zhang Xinyu Wen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1239-1261,共23页
In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tens... In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tension output,this paper proposed a tension fluctuation rejection strategy based on feedforward compensation.In addition to the bias harmonic curve of the unknown state,the tension fluctuation also contains the influence of bounded noise.A tension fluctuation observer(TFO)is designed to cancel the uncertain periodic signal,in which the frequency generator is used to estimate the critical parameter information.Then,the fluctuation signal is reconstructed by a third-order auxiliary filter.The estimated signal feedforward compensates for the actual tension fluctuation.Furthermore,a time-varying parameters fractional-order PID controller(TPFOPID)is realized to attenuate the bounded noise in the fluctuation.Finally,TPFOPID is enhanced by TFO and applied to control a tension control system considering multi-source disturbances.The stability of the method is analyzed by using the Lyapunov theorem.Finally,numerical simulations verify that the proposed scheme improves the tracking ability and robustness of the system in response to tension fluctuations. 展开更多
关键词 Constant tension control anti-fluctuation strategy tension fluctuation observer time-varying parameters fractional-order PID controller feedforward compensate
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Atomistic evaluation of tension–compression asymmetry in nanoscale body-centered-cubic AlCrFeCoNi high-entropy alloy
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作者 邢润龙 刘雪鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期613-622,共10页
The tension and compression of face-centered-cubic high-entropy alloy(HEA) nanowires are significantly asymmetric, but the tension–compression asymmetry in nanoscale body-centered-cubic(BCC) HEAs is still unclear. In... The tension and compression of face-centered-cubic high-entropy alloy(HEA) nanowires are significantly asymmetric, but the tension–compression asymmetry in nanoscale body-centered-cubic(BCC) HEAs is still unclear. In this study,the tension–compression asymmetry of the BCC Al Cr Fe Co Ni HEA nanowire is investigated using molecular dynamics simulations. The results show a significant asymmetry in both the yield and flow stresses, with BCC HEA nanowire stronger under compression than under tension. The strength asymmetry originates from the completely different deformation mechanisms in tension and compression. In compression, atomic amorphization dominates plastic deformation and contributes to the strengthening, while in tension, deformation twinning prevails and weakens the HEA nanowire.The tension–compression asymmetry exhibits a clear trend of increasing with the increasing nanowire cross-sectional edge length and decreasing temperature. In particular, the compressive strengths along the [001] and [111] crystallographic orientations are stronger than the tensile counterparts, while the [110] crystallographic orientation shows the exactly opposite trend. The dependences of tension–compression asymmetry on the cross-sectional edge length, crystallographic orientation,and temperature are explained in terms of the deformation behavior of HEA nanowire as well as its variations caused by the change in these influential factors. These findings may deepen our understanding of the tension–compression asymmetry of the BCC HEA nanowires. 展开更多
关键词 high-entropy alloys body-centered-cubic NANOWIRE tension–compression asymmetry atomistic simulations
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Impact of Tension-Type Headaches in the Workplace in Brazzaville
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作者 Happhia Dinah Boubayi Motoula Latou Josué Euberma Diatewa +4 位作者 Ghislain Armel Mpandzou Prince Eliot Galieni Sounga Bandzouzi Jean Brice Mouendenguia Karen Lise Obondzo Aloba Paul Macaire Ossou-Nguiet 《Neuroscience & Medicine》 2024年第2期77-91,共15页
Introduction: Tension-type headaches are the most widespread of the primary headache disorders. Due to their high prevalence, tension-type headaches represent a major public health problem with an enormous socio-econo... Introduction: Tension-type headaches are the most widespread of the primary headache disorders. Due to their high prevalence, tension-type headaches represent a major public health problem with an enormous socio-economic burden. Determining their impact remains a challenge. Objective: To assess the impact of occupational tension-type headache in Brazzaville and identify associated factors. Population and Methods: This was an analytical case-control study conducted in public and private companies in the city of Brazzaville over a period of four (04) months. The case population consisted of cephalalgic employees;the control population was drawn from the same companies and was free of tension-type headaches. Study variables were divided into socio-professional, clinical and individual impact variables. Individual impact variables were represented by: the HIT-6 score, which incorporates a very broad conception of disability, covering several domains, namely: severity of pain during attacks and the restrictive and limiting nature of attacks. Results: Individual impact was severe in 18 (62.1%) men and 11 (37.9%) women. Mean age was 36.3 6.14 years for cases with severe impact. The mean duration of headache was 40.3 32.7 months for cases with severe impact. Tension headache evolved in attacks in 22 (75.9%) cases with severe impact, and continuously in seven (24.1%) cases. The average number of attacks per month was 2.52 1.04 for cases with severe impact. Cases with severe impact included 14 (48.3%) with chronic headache and 15 (51.7%) with episodic headache. Pain of severe intensity present in 48.3% of cases was associated with a severe impact of tension-type headache: OR = 151.66 [2.36 - 44245.95] and p-value = 0.037. At least one days absence from work per year was observed in 47.4% of our cases. The number of days off work per year due to tension-type headache had an interquartile range between 0 and 3 days and extremes from 0 to 14 days. It was the consequence of a severe impact on daily and/or professional activities. Conclusion: The high frequency of tension-type headaches in the workplace and its impact on the condition of workers in Brazzaville represent a real public health problem. It was found that the number of days absent from work per year due to tension headaches was the consequence of a severe impact on daily and/or professional activities. An awareness-raising program in this environment seems necessary, as well as an assessment of working conditions. 展开更多
关键词 IMPACT tension Headache WORKPLACE
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Eudragit®-PEG Nanoparticles: Physicochemical Characterization and Interfacial Tension Measurements
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作者 Papa Mady Sy Sidy Mouhamed Dieng +4 位作者 Alphonse Rodrigue Djiboune Louis Augustin Diaga Diouf Boucar Ndong Gora Mbaye Mounibé Diarra 《Open Journal of Biophysics》 2024年第2期121-131,共11页
The objectives of this study are to understand the mechanisms involved in the stabilization of water/oil interfaces by polymeric nanoparticles (NPs) (Eudragit®). Eudragit L100 NPs of various sizes and Zeta potent... The objectives of this study are to understand the mechanisms involved in the stabilization of water/oil interfaces by polymeric nanoparticles (NPs) (Eudragit®). Eudragit L100 NPs of various sizes and Zeta potentials were studied and compared at a water/cyclohexane model interface using a droplet tensiometer (Tracker Teclis, Longessaigne, France). The progressive interfacial adsorption of the NPs in the aqueous phase was monitored by tensiometry. The model interface was maintained and observed in a drop tensiometer, analyzed via axisymmetric drop shape analysis (ADSA), to determine the interfacial properties. Given the direct relationship between the stability of Pickering emulsions (emulsions stabilized by solid nanoparticles) and the interfacial properties of these layers, different nanoparticle systems were compared. Specifically, Eudragit NPs of different sizes were examined. Moreover, the reduction of the Zeta potential with PEG-6000 induces partial aggregation of the NPs (referred to as NP flocs), significantly impacting the stability of the interfacial layer. Dynamic surface tension measurements indicate a significant decrease in interfacial tension with Eudragit® nanoparticles (NPs). This reduction correlates with the size of the NPs, highlighting that this parameter does not operate in isolation. Other factors, such as the contact angle and wettability of the nanoparticles, also play a critical role. Notably, larger NPs further diminished the interfacial tension. This study enhances our understanding of the stability of Pickering emulsions stabilized by Eudragit® L100 polymeric nanoparticles. 展开更多
关键词 NANOPARTICLES Eudragit® PEG Interfacial tension Pickering Emulsion
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What diameter?What height?Influence of measures of average tree size on area-based allometric volume relationships
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作者 Yilin Wang John A.Kershaw +2 位作者 Mark J.Ducey Yuan Sun James B.McCarter 《Forest Ecosystems》 SCIE CSCD 2024年第1期100-109,共10页
Volume is an important attribute used in many forest management decisions.Data from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and he... Volume is an important attribute used in many forest management decisions.Data from 83 fixed-area plots located in central New Brunswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume equation.When density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height measure.When density was not included(Volume=f(Diameter,Height)),the opposite was true.For models with density included,moment-based estimators of stand diameter and height performed better than all other measures.For models without density,largest tree estimators of stand diameter and height performed better than other measures.The overall best equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The best equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height subsampling and LiDAR-derived forest inventory analyses. 展开更多
关键词 Allometric relationships Stand structure Volume estimation Stand-level attributes
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Neuroimaging in atypical normal tension glaucoma:debating routine implementation in the absence of classic neurological findings
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作者 Umay Güvenç Gülizar Demirok +1 位作者 Güner Üney Selma Uzman 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期509-517,共9页
●AIM:To assess the necessity of neuroimaging in patients with neurological or atypical findings of normal tension glaucoma(NTG)who do not exhibit typical glaucoma manifestations.●METHODS:A retrospective analysis was... ●AIM:To assess the necessity of neuroimaging in patients with neurological or atypical findings of normal tension glaucoma(NTG)who do not exhibit typical glaucoma manifestations.●METHODS:A retrospective analysis was conducted on 90 atypical NTG patients who underwent cranial magnetic resonance imaging(MRI)due to atypical symptoms.The demographic characteristics,clinical parameters,and radiological findings were recorded.●RESULTS:Among the patients,66.7%had abnormal radiology results,with the most common findings being gliosis(34.4%),sequelae of cerebrovascular events and vascular malformations(14.4%),and benign intracranial mass lesions(11%).Non-glaucomatous visual field defects were more frequently observed in patients with abnormal neuroimaging results.However,there were no significant differences in intraocular pressure,optic disc parameters,retinal nerve fiber layer thickness,and visual field indices between patients with normal and abnormal radiological results.The mean age of the patients was 58.74y.Interestingly,there was a significant age difference,with the abnormal radiology group having a higher median age(P=0.021).●CONCLUSION:The study highlights the importance of cranial imaging in older NTG patients to detect underlying pathologies and prevent misdiagnosis.It suggests that neuroimaging may be warranted in NTG patients with atypical visual field defects incompatible with glaucoma.However,routine neuroimaging in all NTG patients without classic neurological signs may not be necessary. 展开更多
关键词 normal tension glaucoma NEUROIMAGING atypical visual field defects
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Mechanical behavior of rock under uniaxial tension:Insights from energy storage and dissipation
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作者 Guanshuang Tan Chunde Ma +3 位作者 Junjie Zhang Wenyuan Yang Guiyin Zhang Zihao Kang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2466-2481,共16页
Many rock engineering projects show that the growth of tensile cracks is often an important cause of engineering disasters,and the mechanical behavior of rocks is essentially the transmission,storage,dissipation and r... Many rock engineering projects show that the growth of tensile cracks is often an important cause of engineering disasters,and the mechanical behavior of rocks is essentially the transmission,storage,dissipation and release of energy.To investigate the tensile behavior of rock from the perspective of energy,uniaxial tension tests(UTTs)and uniaxial compression tests(UCTs)were carried out on three typical rocks(granite,sandstone and marble).Different unloading points were set before the peak stress to separate elastic energy and dissipated energy.The input energy density ut,elastic energy density ue,and dissipated energy density ud at each unloading point were calculated by integrating stress-strain curves.The results show that there is a strong linear relationship between the three energy parameters and the square of the unloading stress in UCT,but this linear relationship is weaker in UTT.The ue and ud increase linearly with the increase in ut in UCT and UTT.Based on the phenomenon that ue and ud increase linearly with ut,the applicability of Wp et index in UTT was proved and the relative energy storage capacity and absolute energy distribution characteristics of three rocks in UCT and UTT were evaluated.The tensile behavior of marble and sandstone in UTT can be divided into two stages vaguely according to the energy distribution,but granite is not the case.In addition,based on dissipated energy,the damage evolution of three types of rocks in UCT and UTT was discussed.This study provides some new insights for understanding the tensile behavior of rock. 展开更多
关键词 Uniaxial tension Energy density Mechanical behavior Energy storage coefficient Energy dissipation coefficient
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Geometry and formation mechanism of tension gashes and their implication on the hydrocarbon accumulation in the deep-seated strata of sedimentary basin:A case from Shunnan area of Tarim Basin
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作者 Yan-Nan Du Kong-You Wu +4 位作者 Yin Liu Yan-Ying Li Zi-Cheng Cao You-Wei Cui Jun Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期87-99,共13页
With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention recently.Affected by multi-stage tectonic ... With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention recently.Affected by multi-stage tectonic movements,the strike-slip faults have controlled the distribution of hydrocarbon resources owing to the special fault characteristics and fault-related structures.In contrast,the kinematics and formation mechanism of strike-slip faults in buried sedimentary basins are difficult to investigate,limiting the discussion of these faults and hydrocarbon accumulation.In this study,we identified the characteristics of massive sigmoidal tension gashes(STGs)that formed in the Shunnan area of the Tarim Basin.High-resolution three-dimensional seismic data and attribute analyses were used to investigate their geometric and kinematic characteristics.Then,the stress state of each point of the STGs was calculated using seismic curvature attributes.Finally,the formation mechanism of the STGs and their roles in controlling hydrocarbon migration and accumulation were discussed.The results suggest that:(1)the STGs developed in the Shunnan area have a wide distribution,with a tensile fault arranged in an enéchelon pattern,showing an S-shaped bending.These STGs formed in multiple stages,and differential rotation occurred along the direction of strike-slip stress during formation.(2)Near the principal displacement zone of the strike-slip faults,the stress value of the STGs was higher,gradually decreasing at both ends.The shallow layer deformation was greater than the deep layer deformation.(3)STGs are critical for connecting source rocks,migrating oil and gas,sealing horizontally,and developing efficient reservoirs.This study not only provides seismic evidence for the formation and evolution of super large STGs,but also provides certain guidance for oil and gas exploration in this area. 展开更多
关键词 Tarim Basin Sigmoidal tension gashes Seismic attributes Shear stress calculation Formation mechanism Reservoir control
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Three anti-inflammatory polysaccharides from Lonicera japonica Thunb.:insights into the structure-function relationships
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作者 Yu Liu Hongjing Dong +5 位作者 Dongxiao Sun-Waterhouse Wenwen Li Bin Zhang Jinqian Yu Zhichang Qiu Zhenjia Zheng 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2197-2207,共11页
This study demonstrates the feasibility of producing three polysaccharides(neutral LJP-1,acidic LJP-2 and acidic LJP-3)with significant in vitro and in vivo anti-inflammatory activities from the flowers of Lonicera ja... This study demonstrates the feasibility of producing three polysaccharides(neutral LJP-1,acidic LJP-2 and acidic LJP-3)with significant in vitro and in vivo anti-inflammatory activities from the flowers of Lonicera japonica.The three polysaccharides differed in chemical composition,molecular weight(Mw)distribution,glycosidic linkage pattern,functional groups and morphology.They exhibited excellent protective effects(in a dose-dependent manner)in lipopolysaccharide-injured RAW264.7 macrophages and Cu SO4-damaged zebrafish via reducing NO production and inhibiting the overexpressions of inflammation-related transcription factors,inflammatory proteins and cytokines in the NF-κB/MAPK signaling pathways.Their antiinflammatory effects varied owing to their different molecular characteristics and chemical compositions.Overall,LJP-2 at 400μg/m L was the most effective.LJP-2 consisted mainly of→5)-α-L-Araf(1→,→4)-α-LGalp A(1→and→2)-α-L-Rhap(1→residues with terminal T-β-D-Glcp.Thus,honeysuckle flowers are good sources of anti-inflammatory polysaccharides,and precise fractionation enables the production of potent antiinflammatory agents for the development of functional foods and healthcare products. 展开更多
关键词 Honeysuckle polysaccharides FRACTIONATION Molecular characteristics Anti-inflammatory properties Structure-function relationship
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Effectivity and safety of trifocal intraocular lenses and capsular tension rings implantation for cataract patients with axial high myopia
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作者 Shan Hua Qiu-Xia Xie +1 位作者 Hu Wang Jing-Xiang Zhong 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期499-508,共10页
●AIM:To assess effectivity and safety of trifocal intraocular lenses(IOLs)and capsular tension rings in treating cataract patients with axial high myopia.●METHODS:A prospective nonrandomized controlled clinical tria... ●AIM:To assess effectivity and safety of trifocal intraocular lenses(IOLs)and capsular tension rings in treating cataract patients with axial high myopia.●METHODS:A prospective nonrandomized controlled clinical trial was conducted.Totally 98 eyes(74 patients)who underwent femtosecond laser-assisted cataract surgery(FLACS)with trifocal IOLs were enrolled in the study and followed up for 2y after surgery:46 eyes(33 patients)with capsular tension ring implantation in the long axial lengths(AL)group(26<AL<29 mm)and 52 eyes(41 patients)in the normal AL group(22<AL<24.5 mm).Postoperative outcomes about effectivity and safety,including the subjective and objective visual quality,and postoperative complications were assessed.●RESULTS:Uncorrected distance visual acuity at 5 m and uncorrected intermediate visual acuity at 60 and 80 cm in the long AL group were significantly worse than those in the normal AL group at 3mo postoperatively(P<0.05).The differences in reading speed,spectacle independence and potential visual complaints between the two groups were not statistically significant(P>0.05).The dysfunctional lens index and total modulation transfer function(MTF)average height were similar between the two groups.The postoperative internal coma aberrations in the axial high myopia eyes were significantly higher than that in the normal AL group(P<0.05).The total satisfaction score in the long AL group(91.32±2.76)was slightly higher than that in the normal AL group(90.36±3.47),but there was no difference(P=0.136).A statistically negative correlation was found between corrected distance visual acuity(CDVA)and dysfunctional lens index(r=-0.382,P=0.009),and between CDVA and the total MTF average height(r=-0.374,P=0.01).But there was no significant correlation between CDVA and total satisfaction score(r=0.059,P=0.696).Postoperative complications mainly presented as posterior capsular opacity(PCO),retinal detachment and cystoid macular edema.There was no difference in the incidence of fundus disease(6.5%vs 3.8%,P=0.663)or PCO(17.4%vs 7.7%,P=0.217)between the two groups at two years.●CONCLUSION:The utilization of trifocal IOL and capsular tension ring implantation is beneficial for cataract patients with axial high myopia undergoing FLACS.This approach not only ensures excellent subjective feelings and objective visual quality,but also does not increase the incidence of postoperative complications. 展开更多
关键词 trifocal intraocular lenses capsular tension ring axial high myopia CATARACT visual quality
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Relationship between Kawasaki disease and abdominal pain
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作者 Yan Pan Fu-Yong Jiao 《World Journal of Clinical Cases》 SCIE 2024年第17期2932-2934,共3页
This editorial presents an analysis of an article recently published in the World Journal of Clinical Cases.Kawasaki disease(KD)is a well-known pediatric vasculitis characterized by fever,rash,conjunctivitis,oral muco... This editorial presents an analysis of an article recently published in the World Journal of Clinical Cases.Kawasaki disease(KD)is a well-known pediatric vasculitis characterized by fever,rash,conjunctivitis,oral mucosal changes,and swelling of the extremities.This editorial aims to delve into the intricate relationship between KD and abdominal pain,drawing insights from recent research findings to provide a comprehensive understanding and potential avenues for future investigation. 展开更多
关键词 Kawasaki disease Abdominal pain relationship RESEARCH INVESTIGATION
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Monitor and Acceptance among Couples in Romantic Relationships:Actor-Partner Interdependence Models Based on the Monitor and Acceptance Theory
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作者 Xue Wen Yuyang Zhou +2 位作者 Jiaxuan Du Xiaoyan Liu Wei Xu 《International Journal of Mental Health Promotion》 2024年第7期589-598,共10页
Communication could be an essential part of couples in their daily life.Based on Monitor and Acceptance Theory(MAT),the present study explored the mediating role of communication in the relationship between mindfulnes... Communication could be an essential part of couples in their daily life.Based on Monitor and Acceptance Theory(MAT),the present study explored the mediating role of communication in the relationship between mindfulness and relationship quality among college-student couples.The research examined the dynamic relationship of monitoring and acceptance to relationship satisfaction in the Actor-Partner Interdependence Model(APIM),and the mediating effect of positive or negative communications in these relationships.A total of 96 pairs of couples in the universities in Nanjing,China participated in the research.Momentary measurements were used to measure the momentary levels of their monitor,acceptance,positive/negative communication,and relationship satisfaction.A Hierarchical Linear Model(HLM)was used to deal with the APIM.Results showed that the women’s monitor facet of state mindfulness negatively predicted men’s relationship satisfaction through women’s negative communication,and the women’s acceptance facet of state mindfulness positively predicted women’s relationship satisfaction through women’s positive and negative communication at the within-person level.The study highlights the importance of cooperation in monitoring and acceptance for couples to own and hold high levels of relationship satisfaction. 展开更多
关键词 Romantic relationship communication MINDFULNESS MONITOR ACCEPTANCE
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Elucidating the structure-activity relationship of Cu-Ag bimetallic catalysts for electrochemical CO_(2) reduction
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作者 Qining Huang Lili Wan +1 位作者 Qingxuan Ren Jingshan Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期345-351,I0009,共8页
Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential fo... Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential for catalyst design.Herein,we prepared two Cu-Ag bimetallic catalysts with Ag nanoparticles attached to the top or the bottom of Cu nanowires.When tested in a flow cell,the Cu-Ag catalyst with Ag nanoparticles on the bottom achieved a faradaic efficiency of 54%for ethylene production,much higher than the catalyst with Ag nanoparticles on the top.The catalysts were further studied in the H-cell and zero-gap MEA cell.It was found that placing the two metals in the intensified reaction zone is crucial to triggering the tandem reaction of bimetallic catalysts.Our work elucidates the structure-activity relationship of bimetallic catalysts for CO_(2) reduction and demonstrates the importance of considering both catalyst structures and cell characteristics to achieve high activity and selectivity. 展开更多
关键词 Electrochemical CO_(2)reduction Bimetallic catalyst CU-AG Structure-activity relationship
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Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems
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作者 G.Wilson FERNANDES Letícia RAMOS +3 位作者 Dario C.PAIVA Jéssica CUNHA-BLUM Vanessa Matos GOMES Daniel NEGREIROS 《Journal of Mountain Science》 SCIE CSCD 2024年第3期719-733,共15页
Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferrugin... Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low resilience.The determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological restoration.We proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic composition.We described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and soils.All three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia subalata.The distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt concentration.We provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local conditions.Failure to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem services.This study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem. 展开更多
关键词 Canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships
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The Relationship between Father-Love Absence and Loneliness:Based on the Perspective of the Social Functionalist Theory and the Social Needs Theory
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作者 Yaping Zhou He Zhong +1 位作者 Xiaojun Li Yanhui Xiang 《International Journal of Mental Health Promotion》 2024年第2期139-148,共10页
Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-lov... Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-love absence on individual loneliness are not clear.Based on the social functionalist theory and the social needs theory,this study examines the influence of individual fatherlove absence on loneliness and its underlying mechanisms.A questionnaire survey was administered to 319 junior high school students and 1,476 high school students.The results showed that adolescents with father-love absence had higher levels of loneliness,and that father-love absence affected loneliness levels through mediating pathways of individual gratitude,peer relationships,and gratitude to peer relationships.This study not only confirms the negative effects of father-love absence on adolescents’loneliness,but also explains the mediate roles of individual gratitude and peer relationships.It enriches the theoretical system related to family education and has important theoretical and practical implications for further interventions on adolescents’mental health from the perspective of fatherless parenting. 展开更多
关键词 Father-love absence LONELINESS GRATITUDE peer relationships
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Different mechanisms underlie similar species-area relationships in two tropical archipelagoes
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作者 Shengchun Li Tieyao Tu +5 位作者 Shaopeng Li Xian Yang Yong Zheng Liang-Dong Guo Dianxiang Zhang Lin Jiang 《Plant Diversity》 SCIE CAS CSCD 2024年第2期238-246,共9页
Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelag... Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China Sea.We found positive plant species-area relationships for both coral and continental archipelagoes.However,our results showed that different mechanisms contributed to similar plant species-area relationships between the two archipelagoes.For coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species diversity.By contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental islands.Intriguingly,increasing soil nutrients availability(N,P,K)had opposite effects on plant diversity between the two archipelagoes.In summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental islands.More generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands. 展开更多
关键词 Coral and continental islands Plant diversity Soil nutrients Species-area relationships The sampling effect
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Modern pollen-vegetation relationships along altitudinal vegetation belts in the Leigong Mountain of southwestern China
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作者 LI Shuming ZHAO Wenwei +7 位作者 WEI Lisi REN Weihe GU Qinran WU Siqi JI Yang YANG Ziteng ZHUANG Rui CHEN Chunzhu 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2249-2262,共14页
Understanding the distribution,dispersal,and correlation of modern pollen with vegetation in mountainous regions is essential for establishing accurate modern analogs for fossil pollen records.This study,conducted in ... Understanding the distribution,dispersal,and correlation of modern pollen with vegetation in mountainous regions is essential for establishing accurate modern analogs for fossil pollen records.This study,conducted in Leigong Mountain on the YunnanGuizhou Plateau of southwestern China,involved the collection of 35 surface soil samples from diverse vegetation communities along an elevational gradient ranging from 1210 to 1875 meters.The results reveal a close correspondence between modern pollen assemblages and vegetation zones.Principal Component Analysis(PCA)results indicate that pollen assemblages can effectively distinguish between subtropical montane evergreen broad-leaved forest(SEBF)and subtropical montane deciduous broadleaved forest(SDBF).However,both SEBF and SDBF show significant overlap with subtropical montane evergreen-deciduous broad-leaved mixed forest(SEMF).Detrended Correspondence Analysis(DCA)results clearly distinguish the three vegetation zones,and the first axis of DCA shows a significant positive correlation with elevation(p<0.01,R=0.48).Discriminant Analysis(DA)successfully assigns 94.4%of the modern pollen samples to their respective vegetation zones.Pollen taxa such as Impatiens,Astertype,and Rosaceae exhibit significant indicative capabilities for the SEBF zone,effectively distinguishing this vegetation zone from others.Pinus and Alnus display overrepresentation in the Leigong Mountain region,while Quercus(D,deciduous-type)and Poaceae exhibit high representation in the SEBF zone.In the SEBF zone,both pollen diversity and richness are the lowest.Our study reveals the complex relationship between the richness and diversity of pollen and vegetation.The diversity and richness of tree and shrub pollen are found to be lower than those of the corresponding plants.The pollen-vegetation relationship elucidated in this study serves as a critical reference for reconstructing ancient environments from fossil pollen retrieved in this region. 展开更多
关键词 Modern pollen assemblages Pollenvegetation relationship Pollen diversity and richness Leigong Mountain Southwestern China
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Predicting Users’ Latent Suicidal Risk in Social Media: An Ensemble Model Based on Social Network Relationships
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作者 Xiuyang Meng Chunling Wang +3 位作者 Jingran Yang Mairui Li Yue Zhang Luo Wang 《Computers, Materials & Continua》 SCIE EI 2024年第6期4259-4281,共23页
Suicide has become a critical concern,necessitating the development of effective preventative strategies.Social media platforms offer a valuable resource for identifying signs of suicidal ideation.Despite progress in ... Suicide has become a critical concern,necessitating the development of effective preventative strategies.Social media platforms offer a valuable resource for identifying signs of suicidal ideation.Despite progress in detecting suicidal ideation on social media,accurately identifying individuals who express suicidal thoughts less openly or infrequently poses a significant challenge.To tackle this,we have developed a dataset focused on Chinese suicide narratives from Weibo’s Tree Hole feature and introduced an ensemble model named Text Convolutional Neural Network based on Social Network relationships(TCNN-SN).This model enhances predictive performance by leveraging social network relationship features and applying correction factors within a weighted linear fusion framework.It is specifically designed to identify key individuals who can help uncover hidden suicidal users and clusters.Our model,assessed using the bespoke dataset and benchmarked against alternative classification approaches,demonstrates superior accuracy,F1-score and AUC metrics,achieving 88.57%,88.75%and 94.25%,respectively,outperforming traditional TextCNN models by 12.18%,10.84%and 10.85%.We assert that our methodology offers a significant advancement in the predictive identification of individuals at risk,thereby contributing to the prevention and reduction of suicide incidences. 展开更多
关键词 Suicide risk prediction social media social network relationships Weibo Tree Hole deep learning
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Hubble Tension Explanation from This Cosmological Model AΛΩ (Slow Bang Model, SB)
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作者 Jean Perron 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期106-125,共20页
In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of t... In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of the evolution of space-time as well as an equation of state that retains all the infinitesimal terms. We find an explanation of the Hubble tension H<sub>0</sub>. Indeed, we have seen that this constant depends on the transceiver pair which can vary from the lowest observable value, from photons of the CMB (theoretical [km/s/Mpc]) to increasingly higher values depending on the earlier origin of the formation of the observed galaxy or cluster (ETG ~0.3 [Gy], ~74 [km/s/Mpc]). We have produced a theoretical table of the values of the constant according to the possible pairs of transmitter/receiver in the case where these galaxies follow the Hubble flow without large disturbance. The calculated theoretical values of the constant are in the order of magnitude of all values mentioned in past studies. Subsequently, we applied the models to 9 galaxies and COMA cluster and found that the models predict acceptable values of their distances and Hubble constant since these galaxies mainly follow the Hubble flow rather than the effects of a galaxy cluster or a group of clusters. In conclusion, we affirm that this Hubble tension does not really exist and it is rather the understanding of the meaning of this constant that is questioned. 展开更多
关键词 Model of the Universe Cosmological Constant Hubble Constant Hubble’s tension Hubble-Lemaître Law Hubble’s Flow
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Relationship between Inter Canine Width and Inter Alar Width, Inter Commissural Width, and Inter Canthal Distance: A Pilot Study
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作者 Grevisse Bindele Ndombolo Augustin Mantshumba Milolo +5 位作者 Fidele Nyimi Bushabu Em Kalala Kazadi Pierrot Kumpanya Ntumba Jean Marie Kayembe Bukama Elias Lubadi Tshilumba Jean Paul Sekele Isouradi 《Open Journal of Stomatology》 2024年第6期279-290,共12页
The aim of this study was to determine the relationship between inter canine width (ICW) and inter alar width (IAW), inter commissural width (ICoW), and inter canthal distance (ICaD) in Bantu population. Materials and... The aim of this study was to determine the relationship between inter canine width (ICW) and inter alar width (IAW), inter commissural width (ICoW), and inter canthal distance (ICaD) in Bantu population. Materials and Methods: It was a pilot study included all participants who were aged at least 18 years, without a history of orthodontics treatment from Prosthodontics Department, Faculty of Dental Medicine, University of Kinshasa. The Ethics committee of the National Center of Research for Dental Sciences in DR Congo approved the study protocol (CNRSB 1504.218). The participants medical records were obtained from the interview and dental examination. Nature of the study was explained with participant information sheet, and an informed consent of all participants was obtained. The inclusion criteria were no missing maxillary and mandibular teeth, no diastema, and no anterior restorations, 18 years old before enrollment in the study. The exclusion criteria were inability to meet the above requirements, pregnancy, and refusal to participate in the study. The inter-canine width (ICW), inter alar width (IAW), inter canthal distance (ICaD) and inter-commissural width (ICoW) of each participant were measured with a digital Vernier caliper (Mitutoyo, UK Ltd.,) (0.01 mm) three times and the average value was recorded. The inter canthal distance (ICaD) was measured without applying pressure by bringing the recording parts of the caliper just in contact with the medial angle. The inter alar width (IAW) was marked with a fine marked pencil on the widest outer surface of the alae of the nose on either side or width. Those two points were measured without applying pressure by bringing the recording parts of the caliper just in contact with the outer surface. The participant was told to stop breathing shortly to avoid any change in shape of the nose. The inter-commissural width (ICoW) was determined by measuring the maxillary lip vermilion from commissure to commissure without the application of pressure on the tissue in the relaxed state. The inter-canine width (ICW) was measured indirectly using a dental floss. A dental floss was marked on one end prior to placement in the mouth. Using that point as reference, the dental floss was circumference along the curvature of the anterior dentition such that it passed along the contact point of all the teeth. The distal end of the canine teeth on both sides was then marked on the floss while it was stretched in the patients mouth. Floss was marked on both sides with the marker pencil. The distance between the two proximal contact points was measured and recorded. Data, analysis and validation were performed by the SPSS software (version 22.0, IBM SPSS Statistics, Chicago, IL, USA). Unpaired t-test was used, of Kolmogorov-Smirnov test. Analysis of variance (ANOVA) test was used to test for comparability between socio-demographic characteristics dental measurements. Pearsons correlation coefficients test was calculated to determine the relationship between facial and dental parameters. Significance was set at P 0.01. Results: Of 314 participants enrolled, 202 were included. The age ranged from 18 to 68 years, with a mean age of 40.62 12.99 years. Although the Pearsons correlation coefficients were negative. Ninety-three participants (46%) were men and one hundred and nine (54%) were women. The overall mean age was 40.62 12.99 years. Facial and dental measurements were greater in women than men with significant differences for ICW (p = 0.04). However, no significant difference was seen between men and women for IAW, ICaD and ICoW (p = 0.44, p = 0.23, p = 0.31 respectively). The correlation including Pearsons correlation coefficient and P-values for all participants is not demonstrated. Conclusion: Within the limitations of this study, the results suggest that IAW, ICaD and ICoW cannot be used as a preliminary method for determining the width of the maxillary for anterior teeth for edentulous patients. 展开更多
关键词 relationship Inter-Canine Width Inter Alar Width Inter Canthal Distance Inter Commissural Width
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