999 research outputs found
Sponge-associated fungi and their bioactive compounds - the Suberites case
No full textSpecimens of Suberites domuncula that had been cultured in aquaria for 4 weeks were analyzed for their associated fungi. A total of 81 fungal strains belonging to 20 different genera was isolated and identified by morphological and molecular methods. The most frequently isolated taxa were Cladosporium spp., Penicillium spp., Petriella sp., Phialophora spp. and Engyodontium album. Based on chromatographic and mass spectrometric analysis of fungal extracts, as well as on bioassay results, Aspergillus ustus, Penicillium sp., Petriella sp. and Scopulariopsis sp. were selected for in-depth analysis of their natural products. A total of 19 different fungal metabolites, including three new natural products, was isolated and structurally identified. A. ustus yielded two sesquiterpenes, a drimane derivative and deoxyuvidin, as well as a sesterterpene ophiobolin H. The drimane derivative had an ED50 value against L5178Y cells of 1.9 mu g ml(-1) in vitro. The crude extract of Petriella sp. was also strongly cytotoxic against the L5178Y cell line. The cyclic tetrapeptide WF-3161 was primarily responsible for the activity; the ED50 value was <0.1 mu g ml(-1). It was identical to the known compound WF-3161 and had been previously isolated from Petriella guttulata. In addition to WF-3161, three further natural products were obtained and unequivocally identified as new derivatives of infectopyrone by one-and two-dimensional NMR spectroscopy and by mass spectroscopy. Of the new compounds, only dihydroinfectopyrone was active against L5178Y cells; the ED50 value was 0.2 mu g ml(-1). Penicillium sp. yielded the largest number of metabolites. Viridicatin, viridicatol, cyclopenin and cyclopenol suppressed larval growth of the polyphagous pest insect Spodoptera littoralis when incorporated into an artificial diet at an arbitrarily chosen concentration of 237 ppm. Viridicatol was the most active compound and had an ED50 value of ca. 50 ppm. Scopulariopsis sp. yielded three metabolites, including the known acetylcholinesterase inhibitors quinolactacin A1 and A2
Pseudosteineria anteramphida Sun & Huang & Tang & Zang & Xiao & Tang 2019, sp. nov
No full text<i>Pseudosteineria anteramphida</i> sp. nov <p>(Figs. 3–4)</p> <p> <b>Type material.</b> Holotype: ♂ 1 on slide WF–21–1; Paratypes ♂ 2, ♂ 3, and ♀ 1, ♀ 2 on slides: WF–23–2; WF–37–1 and WF–37–2, respectively.</p> <p> <b>Type locality and habitat.</b> Specimens were collected from intertidal silt sediment (0–2 cm surface layer) in the Laizhou Bay (37° 11′ 26″ N; 119° 10′ 52″ E).</p> <p> <b>Etymology.</b> The species name is derived from the Latin <i>anter</i> and the Greek <i>amphid</i>, meaning relatively anterior position of amphideal fovea in this species.</p> <p> <b>Measurements.</b> All measurement data are given in Table 2.</p> <p> <b>Description. Males.</b> Body slender, gradually tapering towards both extremities. Cuticle striated, beginning at base of buccal cavity and ending at tail tip. Buccal cavity with hemispherical cheilostom and funnel-shaped pharyngostom. Labial region set off. Six lips slightly inflated. Six inner labial sensilla papilliform. Six outer labial sensilla setiform, strong and stout, 10 µm long. Four cephalic setae, 12–14 µm long, and arranged in one circle with the six outer labial sensilla. Very long subcephalic setae arranged densely in eight short longitudinal rows (subdorsal, laterodorsal, lateroventral and subventral on both sides of body) behind the amphideal fovea, 18 µm from the anterior end. Each group with 5–6 setae, and the length of these setae increasing gradually from anterior to posterior in every row. Length of shortest seta about 7 µm, longest one about 60 µm. Somatic setae short, scattered along the rest of body. Amphideal fovea large, circular, situated between cephalic setae and groups of long subcephalic setae, at a distance of 12 µm from anterior end. Pharynx cylindrical, 185–203 µm (about 20% of total body length). Pharyngo-intestinal junction with conical cardia. Nerve ring located at anterior portion of pharynx (i.e. 35% of pharyngeal length). Excretory-secretory system not observed. Tail conico-cylindrical, 140–146 µm (i.e. equal to 6.4–7.7 anal body diameters in length) long, with distal two fifths cylindrical. Tail tip bearing three terminal setae, up to 20 µm long. Three caudal glands within the tail. Reproductive system diorchic, testes opposed. Anterior testis outstretched and situated to left of intestine; posterior testis reflexed and situated to right of intestine. Both spicules slender, curved, cephalated proximally and tapered distally, equal to 1.8 anal body dimeters in length. Gubernaculum simple, tubular, encloses distal part of the spicule, without apophysis. Precloacal supplements absent. There is a precloacal seta on ventral body side, 10 µm long, 22 µm in front of cloaca.</p> <p> <b>Females.</b> Similar to males in most respects except body slightly larger, subcephalic setae longer (the longest up to 80 µm) and amphideal fovea smaller. Reproductive system monodelphic, one anterior outstretched ovary, stretched forward to the base of pharynx, situated to left of intestine. Postvulaval uterine sac present. Oviduct a wide tube. Uterus a wide tube. Vagina straight. Vulva located at posterior portion of the body (i.e. 65% of the body length from the anterior end), opening via a small pore on ventral body side.</p> <p> <b>Differential diagnosis and discussion.</b> <i>Pseudosteineria anteramphida</i> <b>sp. nov.</b> is characterized by having circular amphideal fovea situated between cephalic setae and the groups of long subcephalic setae, i.e. eight groups of long subcephalic setae are located posterior to amphideal fovea. Curved slender spicules with cephalated proximal end and tapered distal end, equal to 1.8 anal body diameters in length. Tubular gubernaculum without apophysis. No precloacal supplement. The species is very similar to <i>P. ventropapillata</i> Tchesunov, 2000 in the position of groups of long subcephalic setae, but differs from the latter in having shorter body (997–1183 µm vs. 1407–1449 µm), not jointed cephalic setae, no procloacal supplements (vs. 12–14 wart-shaped procloacal supplements) and lacking gubernacular apophysis (vs. presence of gubernacular apophysis). Moreover, the new species is similar to <i>P. pavo</i> and <i>P. sagittispiculata</i> in lacking the gubernacular apophysis. However, the new species differs from <i>P. pavo</i> in having shorter and slenderer male body (962–997 µm, a=25.3–34.4 vs. 1480 µm, a=16.3) and shorter spicules (33–34 µm vs. 56 µm), more posterior position of groups of long subcephalic setae (vs. at level with amphideal fovea). It differs from <i>P. sagittispiculata</i> in posterior position of groups of long subcephalic setae (posterior to amphideal fovea vs. at level with amphideal fovea), shorter cephalic setae (12–14 µm vs. 14-16 µm) and shape of spicules (L-shaped vs. sagittate). Further differences of <i>Pseudosteineria anteramphida</i> <b>sp. nov.</b> from the other species of the genus are specified in the key below.</p>Published as part of <i>Sun, Yan, Huang, Yong, Tang, Hongshuo, Zang, Yu, Xiao, Hui & Tang, Xuexi, 2019, Two new free-living nematode species of the family Xyalidae from the Laizhou Bay of the Bohai Sea, China, pp. 383-394 in Zootaxa 4614 (2)</i> on pages 388-389, DOI: 10.11646/zootaxa.4614.2.7, <a href="http://zenodo.org/record/3242486">http://zenodo.org/record/3242486</a>
MULTIPHOTON DISSOCIATION AND IONIZATION OF Ni(CO), AND VARIOUS COBALT COMPLEXES IN A JET-COOLED MOLECULAR BEAM: COMPARISON WITH MPI OF WF.
No full textAuthor Institution: Department of Chemistry, University of Illinois at ChicagoMutiphoton ionization spectroscopy of Ni(CO), and various cobalt complexes have been investigated. Their MPI spectra exhibited relatively sharp and narrow peaks, namely atomic lines, in the 410-510nm region. Two-photon resonance ionization spectra of metal atoms have been observed in Ni(CO), and cobalt complexes. The multiphoton process for dissociation and ionization in these complexes will be discussed. However, MPI spectra of WF, have exhibited broad bands over the 450-500nm region. The MPI spectra of WF, are quite different than those of Ni(CO), and cobalt complexes: no atomic bands have been observed. The spectra can be instead assigned to three-photon molecular resonance ionization of WF,. All the MPI spectra observed have been assigned and predicted pathways of the MPD/MPI mechanism have been postulated based on energertic thresholds and a power study. Comparison between molecular MPI and atomic MPI in the supersonic jet expansion will be discussed
Tungsten Fibre Reinforced Tungsten (Wf /W) using Yarn Based Textile Preforms
No full textTungsten Fibre Reinforced Tungsten (Wf/W) using Yarn Based Textile PreformsJ.W.Coenena,e,∗,P.Huberb, L.Raumanna, D.Schwalenberga,d, Y.Maoa, J.Rieschc,Ch.Linsmeiera, R.Neuc,da)Forschungszentrum J ̈ulich GmbH, Institut f ̈ur Energie- und Klimaforschung 52425J ̈ulich, Germany,b)Institut f ̈ur Textiltechnik (ITA) der RWTH Aachen University,Aachen, Germany,c)Max-Planck-Institut f ̈ur Plasmaphysik, 85748 Garching,Germany,d)Technische Universit ̈at M ̈unchen, 85748 Garching, Germany,e)Department of Engineering Physics, University of Wisconsin Madison, WI 53706Madison, USAMaterial issues pose a significant challenge for the design of future fusion reactors.Tungsten (W) is the main candidate material as it is resilient against erosion, has thehighest melting point of any metal and shows rather benign transmutations under neu-tron irradiation. However, W is intrinsically brittle and faces operational embrittlement.To overcome these issues new advanced materials are being developed. W-fibre re-inforced W-composite material (Wf/W) incorporates extrinsic toughening mechanismsallowing the redistribution of stress peaks and thus allowing steps towards applica-tion in a future fusion reactor. Recently progress has been made towards fully densemulti short-fibre powder metallurgical production of Wf/W [2] as well as optimising theprocess understanding for the routes using chemical deposition [3].In this contribution the recent status for the Wf/W production will be given with a focuson the introduction of advanced textile preforms produced from W-yarns [1]. In thepast, typically monofilamantes with a diameter of150μm(OSRAM) have been used toweave textile preforms to facilitate large scale production of e.g. for CVD-Wf/W [3].However, the high stiffness of the tungsten fibers with 150 um diameter oftenpresents some challenges, i.e. positioning of a flat preform during the CVD processes.Here less stiff16μmor25μmfibres can be used where the strength of the16μmfibresis at4500MPa[3] and thus significant higher than the strength of the150μmfibre.After the initial success in yarn production [1] a larger amount of yarns were indus-trially produced at Bossert&Kast and used for Weaving. The superior weavability ofthe yarn allows a much more flexible textile preform to be manufactured. Here threetypes of weaves are being compared, firstly of course the original monofilamant basedweave and then the yarn based options utilising first a classical50μmtungsten fila-ment in the weft direction and a second one utilising the identical yarn type in bothwarp and weft direction. Testing of these weaves in the CVD (Wf/W) production isessential to optimise density and fibre volume fraction.For the individual yarns already a dense infiltration is observed and needs nowto be established for the woven product. Modelling shows that utilising a yarn basedweave and thus making the layer placement more accurate, which is crucial to allowWf/W production with optimal density and mechanical properties.[1] Coenen J.W. et al.Physica Scripta, IOP, T171, 014061, (2020).[2] Mao, Y. et al.Composites Part A:,Elsevier BV, 2018, 107, 342-353.[3] Gietl, H. et al.Journal of Composite Materials, (2018), 002199831877114.∗Corresponding Author: tel +492461615536 e-mail [email protected]
Corn-bran: Alternative cellulosic filler for polypropylene
No full textIn this study, the use-ability of corn bran (CB) as a reinforcing filler in polypropylene (PP) matrix was investigated. The properties of CB/PP composites were compared with wood fiber (WF) filled PP composites. In order to enhance the interfacial adhesion, maleated-PP (PP-g-MAH) (MaPP) was used. The CB/PP and WF/PP composites were compounded in an Xplore laboratory compounder. The CB/PP/MaPP and WF/PP/MaPP composites were characterized by tensile test, differential scanning calorimetry (DSC), thennogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The morphology investigated by scanning electron microscopy (SEM). It was shown that corn bran can be an alternative candidate to be used as a reinforcing natural filler source for thermoplastic composites
Induction of virulence variants of the entomopathogenic fungus, Nomuraea rileyi, against the common cutworm, Spodoptera litura
No full textInduction of virulence variants of the entomopathogenic fungus, Nomuraea rileyi, against the common cutworm, Spodoptera litura
Hwei-Jan Lin
Summary
Nine fungal isolates were collected and purified from the infected larvae found in the field, and identified to be Nomuraea rileyi. Growth of these nine isolates at different temperatures was examined. Conidia of all isolates failed to germinate at 35℃and only few isolates could germinate at 15℃. However, they were capable of germinating at 20-30℃, although their germination rate was different. The TC isolate took 60, 36, and 48 hr to reach 100 % germination at 20, 25, and 30℃, respectively. In the same condition, the TC isolate was superior to others in germination. No mycelial growth was found in all isolates at 15 or 35℃. But 9 isolates grew well and sporulated at 20-25℃. The optimum temperatures for mycelial growth and sporulation were found to be at 20-25℃. None could sporulate at 30℃ except the WF isolate. This isolate was though to be most adaptive to high temperatures comparing with other isolates.
Different larval stages of the common cutworm, Spodoptera litura, varied with susceptibility to N. rileyi. Mortalities of 2nd/3rd, 4th, and 5th instars of S. litura were 70, 40, and 20%, respectively, when inoculated with 1´106 conidia/ml of TC isolate. However 1st and 6th instars were not susceptible to this fungus, indicating that 2nd and 3rd instars were most susceptible to N. rileyi. Among 9 isolates, TC and WF isolates were most pathogenic to insect host as assayed with S. litura larvae.
Exposure of WF and TC isolates to UV light at 254 nm induced 19 and 36 variants, respectively. Variants of TC isolate were more tolerable to UV light than WF isolate’s variants. Bioassay showed that the variants, TC-171, TC3, WF144, WF151, WF167, and WF133, had lower LC50 values than other isolates, and have the potential for microbial control.
Seventeen chemicals were tested for their inhibition to mycelial growth of different variants. All of herbicides and insecticides tested were not inhibitory to isolates of N. rileyi. However, three fungicides including maneb, mancozeb, and copper oxychloride + mancozeb showed inhibition to mycelial growth of TC and WF isolates. The variants, TC-168、WF-61、WF-245 and WF-424, TC-17、TC-68、TC-83、TC-159、TC-168、TC-169 and WF-245, TC-10、TC-19、TC-21、TC-32、TC-45、TC-68、TC-77、TC-83、TC-94、TC-112、TC-138、TC-159、TC-162、TC-164、TC-169、TC-182、WF-61、WF-245、WF-413、WF-424 and WF-650, could grow upon treatments with mancozeb, maneb, and copper oxychloride + mancozeb.中 文 摘 要
自田間採集的九株真菌，在實驗室分離及純粹培養後，經對照檢索表鑑定為綠殭菌 (Nomuraea rileyi)。在此九菌株中，只有少數菌株之孢子可在15℃的低溫下發芽，但除TC株外，發芽率皆不高，培養5天之發芽率僅達50 %。在20-30℃培養各菌株，其發芽率皆可達100 %，但所需之培養時間不同；TC株在溫度為20、25及30℃之下，孢子100 %發芽所需之培養時間，分別為60、36及48小時；在35℃高溫時，則會抑制發芽。相同培養條件下，以TC株之發芽率最高，且孢子發芽所需時間也較其他菌株短。在15℃下，只有少數菌株可行菌絲生長，但生長狀況不佳。以高溫35℃培養時，所有菌株均無生長現象。在20-25℃溫度範圍內，所有菌株均可行菌絲生長，且培養兩週後有產孢現象，顯示最適綠殭菌之生長溫度為20-25℃。所有菌株均可在30℃行菌絲生長，但只有WF株可在30℃產孢，故以WF品系具有較廣的溫度適應性。
斜紋夜蛾(Spodoptera litura)不同齡期幼蟲對本菌之感受性各異；接種TC株菌液之濃度為1´106 conidia/ml時，可造成二及三齡蟲70 %之死亡率，而四齡蟲之死亡率為40 %，五齡蟲之死亡率僅有20 %，而一及六齡幼蟲之死亡率更低，幾乎不受感染，顯示斜紋夜蛾幼蟲以二、三齡蟲對綠殭菌最具感受性，而一齡與六齡幼蟲均無感受性。以S. litura檢定九個綠殭菌菌株的致病性，結果以TC與WF株之致病力最佳。
以UV (254nm)光照射所誘發有效之WF及TC株，各得19及36個變異株，其中WF株對UV光之忍受力較TC株高，但培養時則以TC變異株之生長狀況較WF變異株佳。此55個變異株比親本之WF及TC株增加耐UV光照射之特性。變異株之致病力以TC-171、TC-3、WF-144、WF-154、WF-167與WF-133最高，其LC50值較其他株低，故較具使用於微生物防治之潛力。
田間常用之17種農藥，除大生類三種殺菌劑外，其他十四種藥劑，包括殺蟲劑及殺草劑，均不會抑制菌的生長；大生類殺菌劑對各變異株之抑制作用不同，其中以鋅錳乃浦之抑菌力最強。所有變異株中，以TC-168、WF-61、WF-245與WF-424株之生長最不受鋅錳乃浦限制；以TC-17、TC-68、TC-83、TC-159、TC-168、TC-169株與WF-245株對錳乃浦之耐藥性最高，WF-245株之生長完全不受錳乃浦抑制；而TC-10、TC-19、TC-21、TC-32、TC-45、TC-68、TC-77、TC-83、TC-94、TC-112、TC-138、TC-159、TC-162、TC-164、TC-169、TC-182株與WF-61、WF-245、 WF-413、WF-424與WF-650株對銅錳鋅乃浦之忍受度較其他株高。目 錄
中文摘要------------------------------------------------------------------------I
英文摘要------------------------------------------------------------------------III
誌謝------------------------------------------------------------------------------V
目錄------------------------------------------------------------------------------VI
圖次索引------------------------------------------------------------------------IX
表次索引------------------------------------------------------------------------X壹、前言------------------------------------------------------------------------1
貳、文獻摘述------------------------------------------------------------------3
一、斜紋夜蛾------------------------------------------------------------3
二、綠殭菌---------------------------------------------------------------3
三、綠殭菌對不同寄主之致病力------------------------------------4
四、寄主對不同品系綠殭菌之感受性------------------------------5
五、寄主齡期對綠殭菌致病力之影響------------------------------6
六、病原之接種方式---------------------------------------------------6
七、接種之病原形態---------------------------------------------------7
八、變異株之誘發------------------------------------------------------8
九、農藥對綠殭菌之影響---------------------------------------------8
參、材料與方法--------------------------------------------------------------10
一、 供試昆蟲之飼育--------------------------------------------------10
二、 菌種之採集與培養-----------------------------------------------10
三、 綠殭菌發芽率之測試--------------------------------------------11
四、 綠殭菌之溫度適應性--------------------------------------------12
五、 不同齡期幼蟲對綠殭菌之感受性-----------------------------12
六、 綠殭菌不同菌株致病力之比較--------------------------------13
七、 變異株之誘發與篩選--------------------------------------------13
八、 變異株之致病力--------------------------------------------------14
九、 綠殭菌各變異株對農藥相容性之測試-----------------------14
肆、結果-----------------------------------------------------------------------16
一、 菌種之採集與培養-----------------------------------------------16
二、 綠殭菌發芽率之測試--------------------------------------------16
三、 綠殭菌之溫度適應性--------------------------------------------19
四、 不同齡期幼蟲對綠殭菌之感受性-----------------------------21
五、 綠殭菌不同菌株致病力之比較--------------------------------21
六、 變異株之誘發與篩選--------------------------------------------24
七、 變異株之致病力--------------------------------------------------24
八、 綠殭菌各變異株對農藥相容性之測試-----------------------26
伍、討論-----------------------------------------------------------------------31
一、菌種之採集與培養-----------------------------------------------31
二、綠殭菌發芽率之測試--------------------------------------------31
三、綠殭菌之溫度適應性--------------------------------------------34
四、不同齡期幼蟲對綠殭菌之感受性-----------------------------35
五、綠殭菌不同菌株致病力之比較--------------------------------36
六、變異株之誘發與篩選--------------------------------------------37
七、變異株之致病力--------------------------------------------------38
八、綠殭菌各變異株對農藥相容性之測試-----------------------39
九、 結論-----------------------------------------------------------------41
陸、參考文獻-----------------------------------------------------------------43
圖 次 索 引
圖一、不同溫度培養九個綠殭菌菌株之累積發芽率-----------------18
圖二、不同濃度綠殭菌(TC株)對斜紋夜蛾各齡幼蟲之致死率----22
圖三、斜紋夜蛾三齡蟲對九個綠殭菌菌株之感受性-----------------23
圖四、綠殭菌突變株對斜紋夜蛾三齡蟲致病力之比較--------------25
表 次 索 引
表一、菌種採集地及其感染寄主-----------------------------------------17
表二、九個綠殭菌菌株於不同溫度下培養兩週之生長情形--------20
表三、十七種農藥對綠殭菌(TC與WF株)的抑制效果--------------27
表四、大生類殺菌劑對TC突變株之抑制效果------------------------29
表五、大生類殺菌劑對WF突變株之抑制效果-----------------------3
Long-term warfarin therapy and biomarkers for osteoporosis and atherosclerosis
No full textAbstractBackgroundStroke prevention by warfarin, a vitamin K antagonist, has been an integral part in the management of atrial fibrillation. Vitamin K-dependent matrix Gla protein (MGP) has been known as a potent inhibitor of arterial calcification and osteoporosis. Therefore, we hypothesized that warfarin therapy affects bone mineral metabolism, vascular calcification, and vascular endothelial dysfunction.MethodsWe studied 42 atrial fibrillation patients at high-risk for atherosclerosis having one or more coronary risk factors. Twenty-four patients had been treated with warfarin for at least 12months (WF group), and 18 patients without warfarin (non-WF group). Bone alkaline phosphatase (BAP) and under carboxylated osteocalcin (ucOC) and receptor activator of nuclear factor-kappa B ligand (RANKL) were measured as bone metabolism markers. Reactive hyperemia-peripheral arterial tonometry (RH-PAT) index measured by Endo-PAT2000 was used as an indicator of vascular endothelial function.ResultsThere were no significant differences in patient background characteristics and other clinical indicators between the two groups. In WF group, the ucOC levels were significantly higher than those in the non-WF group (10.3±0.8 vs. 3.4±0.9ng/mL; P<0.01), similarly, the RANKL levels in the WF group were higher than those in the non-WF group (0.60±0.06 vs. 0.37±0.05ng/mL; P=0.007). Moreover, RH-PAT index was significantly lower in the WF group compared to those in the non-WF group (1.48±0.11 vs. 1.88±0.12; P=0.017).ConclusionsLong-term warfarin therapy may be associated with bone mineral loss and vascular calcification in 60–80year old hypertensive patients
Closed-loop model-based wind farm control using FLORIS under time-varying inflow conditions
No full textWind farm (WF) controllers adjust the control settings of individual turbines to enhance the total performance of a wind farm. Most WF controllers proposed in the literature assume a time-invariant inflow, whereas important quantities such as the wind direction and speed continuously change over time in reality. Furthermore, properties of the inflow are often assumed known, which is a fundamentally compromising assumption to make. This paper presents a novel, closed-loop WF controller that continuously estimates the inflow and maximizes the energy yield of the farm through yaw-based wake steering. The controller is tested in a high-fidelity simulation of a 6-turbine wind farm. The WF controller is stress-tested by subjecting it to strongly-time-varying inflow conditions over 5000 s of simulation. A time-averaged improvement in energy yield of 1.4% is achieved compared to a baseline, greedy controller. Moreover, the instantaneous energy gain is up to 11% for wake-loss-heavy situations. Note that this is the first closed-loop and model-based WF controller tested for time-varying inflow conditions (i.e., where the mean wind direction and wind speed change over time) at such fidelity. This solidifies the WF controller as the first realistic closed-loop control solution for yaw-based wake steering.Team Jan-Willem van Wingerde
The relationship between Cantonese lexical development and (sub)lexical characteristics
No full textThis study investigated the lexical and sublexical characteristics, including word
frequency (WF), phonological neighbourhood density (PND) and word length (WL), of a
huge sample of Cantonese-speaking children. Parents of 989 Cantonese-speaking children
aged from 24 to 30 months completed the Cantonese version of the MacAurthur-Bates
Communicative Development Inventory : Words and Sentences (CCDI; Tardif, Fletcher,
Liang, & Kaciroti, 2009). Words from CCDI were coded for PND, WF and WL. The
relationships among vocabulary of the children, PND, WF and WL were examined. Children
were classified into typically developing (TD) and late talker (LT) group and the PND and
WF values of their vocabulary were compared. Results showed that PND and WF were both
strong predictors of children’s lexicons. PND accounted for 62.7% of the variance in the size
of vocabulary and WF also accounted for 8.2% of the variance in vocabulary size. Lexicons
of children with small vocabulary size consisted of words that have high PND and high WF
in Cantonese. This indicated that Cantonese-speaking children could extract statistical
properties of the language in the environment, for both typically developing children and late
talkers.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science
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