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brassinosteroid biosynthesis and signaling:conserved and diversified functions of core genes across multiple plant species

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Plant communications 2024年第9期5卷 72-100页

作者： brian Zebosi Erik Vollbrecht norman b.best Department of Genetics Development and Cell BiologyIowa State UniversityAmesIA 50011USA Interdepartmental Genetics and Genomics Graduate Program Iowa State UniversityAmesIA 50011USA USDA-ARS Plant Genetics Research UnitColumbiaMO 65201USA

brassinosteroids(bRs)are important regulators that control myriad aspects of plant growth and development,including biotic and abiotic stress responses,such that modulating bR homeostasis and signaling presents abundant opportunities for plant breeding and crop *** and other proteins involved in the biosynthesis and signaling of bRs are well understood from molecular genetics and phenotypic analysis in Arabidopsis thaliana;however,knowledge of the molecular functions of these genes in other plant species,especially cereal crop plants,is *** this manuscript,we comprehensively review functional studies of bR genes in Arabidopsis,maize,rice,Setaria,brachypodium,and soybean to identify conserved and diversified functions across plant species and to highlight cases for which additional research is in *** performed phylogenetic analysis of gene families involved in the biosynthesis and signaling of bRs and re-analyzed publicly available transcriptomic *** trees coupled with expression data provide a valuable guide to supplement future research on bRs in these important crop species,enabling researchers to identify gene-editing targets for bR-related functional studies.

关键词： brassinosteroids maize rice Setaria soybean brachypodium Arabidopsis

I-Quiz:An Intelligent Assessment Tool for non-Verbal behaviour Detection

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computer Systems Science & Engineering 2022年第3期40卷 1007-1021页

作者： b.T.Shobana G.A.Sathish Kumar Department of Information Technology Sri Venkateswara College of EngineeringSriperumbudur602117India Department of Electronics and communication Engineering Sri Venkateswara College of EngineeringSriperumbudur602117India

Electronic learning(e-learning)has become one of the widely used modes of pedagogy in higher education today due to the convenience and flexibility offered in comparison to traditional learning *** in Information and communication Technology have eased learner connectivity online and enabled access to an extensive range of learning materials on the World Wide *** covid-19 pandemic,online learning has become the most essential and inevitable medium of learning in primary,secondary and higher *** recent times,Massive Open Online courses(MOocs)have transformed the current education strategy by offering a technology-rich and flexible form of online learning.A key component to assess the learner’s progress and effectiveness of online teaching is the Multiple choice Question(McQ)assessment in most of the MOoc *** exists on the reliability and validity of the assessment component as it raises a qualm whether the real knowledge acquisition level reflects upon the assessment *** is due to the possibility of random and smart guesses,learners can attempt,as McQ assessments are more vulnerable than essay type *** paper presents the architecture,development,evaluation of the I-Quiz system,an intelligent assessment tool,which captures and analyses both the implicit and explicit non-verbal behaviour of learner and provides insights about the learner’s real knowledge acquisition *** I-Quiz system uses an innovative way to analyse the learner non-verbal behaviour and trains the agent using machine learning *** intelligent agent in the system evaluates and predicts the real knowledge acquisition level of learners.A total of 500 undergraduate engineering students were asked to attend an on-Screen McQ assessment test using the I-Quiz system comprising 20 multiple choice questions related to advanced c *** non-verbal behaviour of the learner is recorded using a front-facing camera during t

关键词： E-Learning adaptive and intelligent e-learning systems intelligent tutoring systems emotion recognition non-verbal behaviour knowledge acquisition level

biophysical activity of pulmonary surfactant: an alternative view

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Acta Pharmacologica Sinica 2003年第12期 156-157页

作者： Stephen b HALL M/c nRc-3 Molecular Medicine OR 97201-3098 USA Oregon Health & Science University Portland

Pulmonary surfactant has long been recognized as a potential factor in the development and perpetuation of the acute respiratory distress syndrome(ARDS). Attempts to use therapeutic surfactants in the treatment of ARD... 详细信息

关键词： of that biophysical activity of pulmonary surfactant an alternative view DPPc form

DESIGn　AnD　PREPARATIOn　OF　SILIcOn　nITRIDE　cOMPOSITE　WITH　HIGH　FRAcTURE　TOUGHnESS　AnD　nAcRE　STRUcTURE

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 479-484页

作者： Y Huang H.n Hao Y.L. chen and b.L.Zhou (1)Department of Materials Science and Engineering, Tsinghua University,beijing 100084, china 2)Institute of Metal Research, chinese Academy of Sciences,Shenyang 110015, china ) Tsinghua Univ Beijing China

A new way of designing and preparing silicon nitride ceramic composite with high fracture toughness and nacre structure has been proposed. To mimic the laminated structure of nacre, Si_3n_4 matrix ceramic layer can be obtained through compacting rolling method. To mimic the secondary toughening of nacre structure, Sic whisker is added into Si_3n_4 and acts as the secondary toughening phase. boron nitride (bn)is selected to mimic the organic layer in nacre so as to form the weak interfaces between Si_3n_4 layers. Alumina is added into bn to adjust the bonding strength of the *** Si_3n_4 sheets are stacked into the die after coating with bn. After the removal of the organic matter in them, the green body is hot pressed at 1820℃for 1.5 hours under n_2 atmosphere. The fracture toughness of the so-made Si_3n_4 composite at room temperature is 20.36MPa m￣(1/2), the three-point bending strength at room temperature is 651.47MPa. The crack spreads and deflects along the interface between bn and Si_3n_4 layer and extends through the bn layer into Si_3n_4 layer. The improvement of the fracture toughness may be due to the staircase-shape-like crack which provides the long crack path, the fracture and deformation of Si_3n_4 layer, and the pullout of Sic whiskers from the Si_3n_4 layer.

关键词： secondary toughening,compact rolling silicon nitride nacre Structure

correlating mode-I fracture toughness and mechanical properties of heat-treated crystalline rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 91-101页

作者： Mayukh Talukdar Debanjan Guha Roy T.n.Singh Indian Institute of Technology bombay PowaiMumbai400076India IITb-Monash Research Academy Indian Institute of Technology BombayPowaiMumbai400076India

For the effect of thermal treatment on the mode-I fracture toughness(FT), three crystalline rocks(two basalts and one tonalite) were experimentally investigated. Semi-circular bend specimens of the rocks were prepared following the method suggested by the International Society for Rock Mechanics(ISRM)and were treated at various temperatures ranging from room temperature(25 ℃) to 600 ℃. Mode-I FT was correlated with tensile strength(TS), ultrasonic velocities, and Young’s modulus(YM). Additionally,petrographic and X-ray diffraction analyses were carried out to find the chemical changes resulting from the heat treatment. Further, scanning electron microscopy(SEM) was conducted to observe the micro structural changes when subjected to high temperatures. These experiments demonstrate that heat treatment has a strong negative impact on the FT and mechanical properties of the rocks. From room temperature to 600 ℃, mode-I FT values of massive basalt, giant plagioclase basalt, and tonalite were reduced by nearly 52%, 68%, and 64%, respectively. Also, at all temperature levels, FT and mechanical properties are found to be exponentially correlated. However, the exact nature of the relationship mainly depends on rock type. besides, TS was found to be a better indicator of degradation degree than the mode-I FT. SEM images show that micro crack density and structural disintegration of the mineral grains increase with temperature. These physical changes confirm the observed reduction in the stiffness of heat-treated crystalline rocks.

关键词： Fracture toughness(FT) Tensile strength(TS) Ultrasonic velocity Young's modulus(YM) crystalline rocks

Scale Effects of Geographical Soil Datasets on Soil carbon Estimation in Louisiana,USA:A comparison of STATSGO and SSURGO

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Pedosphere 2011年第4期21卷 491-501页

作者： b. ZHOnG Y. J. XU School of Renewable natural Resources Louisiana State University Agricultural Center Baton Rouge LA 70803 (USA)

Estimation of soil organic carbon （Soc） pools and fluxes bears large uncertainties because Soc stocks vary greatly over geographical space and through time. Although development of the U.S. Soil Survey Geographic Database （SSURGO）, currently the most detailed level with a map scale ranging from 1：12 000 to 1：63 360, has involved substantial government funds and coordinated network efforts, very few studies have utilized it for soil carbon assessment at the large landscape scale. The objectives of this study were to 1） compare estimates in soil organic matter among SSURGO, the State Soil Geographic Database （STATSGO）, and referenced field measurements at the soil map unit; 2） examine the influence of missing data on Soc estimation by SSURGO and STATSGO; 3） quantify spatial differences in Soc estimation between SSURGO and STATScO, specifically for the state of Louisiana; and 4） assess scale effects on soil organic carbon density （SocD） estimates from a soil map unit to a watershed and a river basin scale. Soc was estimated using soil attributes of SSURGO and STATSGO including soil organic matter （SOM） content, soil layer depth, and bulk density. Paired t-test, correlation, and regression analyses were performed to investigate various relations of Soc and SOM among the datasets. There were positive relations of Soc estimates between SSURGO and STATSGO at the soil map unit （R2 = 0.56, n = 86, t = 1.65, P = 0.102; depth： 30 cm）. However, the Soc estimated by STATSGO were 9%, 33% and 36~ lower for the upper 30-cm, the upper l-m, and the maximal depth （up to 2.75 m） soils, respectively, than those from SSURGO. The difference tended to increase as the spatial scale changes from the soil map unit to the watershed and river basin scales. compared with the referenced field measurements, the estimates in SOM by SSURGO showed a closer match than those of STATScO, indicating that the former was more accurate than the latter in Soc estimation, both in spatial and temporal resoluti

关键词： carbon accounting climate change GIS soil organic carbon soil organic matter

Multipliers on Vector-valued L^1-spaces for Hypergroups

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Acta Mathematica Sinica,English Series 2018年第7期34卷 1059-1073页

作者： R.SARMA n.Shravan KUMAR Vishvesh KUMAR Department of Mathematics Indian Institute of Technology Delhi

In this article, we extend the well known Wendel＇s theorem to the context of vector-valued L1-spaces on hypergroups. In this regard, various cases have been studied.

关键词： Vector-valued Ll-spaces hypergroups multipliers translation invariant operators Fouriertransform

Quality assessment and hydrogeochemical characteristics of groundwater in Agastheeswaram taluk, Kanyakumari district, Tamil nadu, India

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chinese Journal Of Geochemistry 2014年第3期33卷 221-235页

作者： Srinivas Y Hudson Oliver D Stanley Raj A chandrasekar n centre for GeoTechnology Manonmaniam Sundaranar University Vel Tech Dr. RR & Dr. SR Technical University Avadi Chennai

The present study investigates the hydrogeochemical characteristics of groundwater quality in Agastheeswaram taluk of Kanyakumari district, Tamil nadu, India. A total of 69 groundwater samples were collected during pre- and post-monsoon periods of 2011–2012. The groundwater quality assessment has been carried out by evaluating the physicochemical parameters such as pH, Ec, TDS, HcO3-, cl-, SO42-, ca2+, Mg2+, na+ and K+ for both the seasons. based on these parameters, groundwater has been assessed in favor of its suitability for drinking and irrigation purpose. Dominant cations for both the seasons are in the order of na+ > ca2+ > Mg2+ > K+ while the dominant anions for post monsoon and pre monsoon have the trends of cl- > HcO3- > SO42- and HcO3- > cl- > SO42-, respectively. Analytical results observed from various indices reveal that the groundwater quality is fairly good in some places. Analytical results of few samples show that they are severely polluted and incidentally found to be near the coasts, estuaries and salt pans in the study area. The Gibbs plot indicates that the majority of groundwater samples fall in rock dominant region, which indicates rock water interaction in the study area. The United States salinity(USSL) diagram shows that the groundwater is free from sodium hazards but the salinity hazard varies from low to very high throughout the study area. This reveals that the groundwater is moderately suitable for agricultural activities. The observed chemical variations in pre-monsoon and post-monsoon seasons may be the effect to rock-water interactions, ion-exchange reactions, and runoff of fertilizers from the surrounding agricultural lands.

关键词：地下水质量评价地下水水质水文特性马里印度水岩相互作用物理化学参数研究区域

The effects of sun exposure on carotenoid accumulation and oxidative stress in the retina of the House Finch(Haemorhous mexicanus)

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chinese birds 2016年第1期7卷 56-67页

作者： Matthew b.Toomey Kevin J.McGraw School of Life Sciences Arizona State University Department of Pathology and Immunology Washington University Medical School

background: Diet-derived carotenoid pigments are concentrated in the retinas of birds and serve a variety of functions, including photoprotection. In domesticated bird species(e.g., chickens and quail), retinal carotenoid pigmentation has been shown to respond to large manipulations in light exposure and provide protection against photodamage. However, it is not known if or how wild birds respond to ecologically relevant variation in sun ***: We manipulated the duration of natural sunlight exposure and dietary carotenoid levels in wild-caught captive House Finches(Haemorhous mexicanus), then measured carotenoid accumulation and oxidative stress in the ***: We found no significant effects of sun exposure on retinal levels of carotenoids or lipid peroxidation, in replicate experiments, in winter(Jan–Mar) and spring/summer(May–June). Dietary carotenoid supplementation in the spring/summer experiment led to significantly higher retinal carotenoid levels, but did not affect lipid peroxidation. carotenoid levels differed significantly between the winter and spring/summer experiments, with higher retinal and lower plasma carotenoid levels in birds from the later ***: Our results suggest that variation in the duration of exposure to direct sunlight have limited influence on intraspecific variation in retinal carotenoid accumulation, but that accumulation may track other seasonal–environmental cues and physiological processes.

关键词： carotenoids Haemorhous mexicanus House Finch Photostress Vision