1,720,987 research outputs found
Proteomic analysis of proteins responsive to drought and low temperature stress in a hard red spring wheat cultivar
Full text linkDrought stress is becoming more prevalent with global warming, and has been shown to have large effects on gluten proteins linked to wheat bread making quality. Likewise, low temperature stress can detrimentally affect proteins in wheat. This study was done to determine the differential abundance of high molecular weight (HMW) glutenin proteins in a drought and low temperature stressed high quality hard red spring wheat cultivar (PAN3478), against a control. The treatments were applied in the greenhouse at the soft dough stage. HMW glutenin proteins were extracted from the flour, and were separated by using two-dimensional gel electrophoresis. Protein spots that had p values lower than 0.05 and fold values equal to or greater than 1.2 were considered to be significantly differentially abundant. These proteins were further analyzed by using tandem mass spectrometry. There was a 1.3 to 1.8 fold change in 17 protein spots due to the cold treatment. The drought treatment caused a 1.3 to 3.8 fold change in 19 protein spots. These spots matched either HMW or low molecular weight (LMW) glutenin subunits. In the latter case, the C subunits of LMW glutenins were notably found to be up-regulated under both stress conditions. All the proteins that have been identified can directly influence dough characteristics. Data are available via ProteomeXchange with the identifier PXD017578
Morphological and genetic characterisation of mango (Mangifera indica L.) varieties in Mozambique
No full textEnglish: Mango (Mangifera indica L.) belongs to the Anacardiaceae family. Consumption is increasing worldwide due its their nutritional value that is rich in vitamins A and C, potassium, β-carotene, fibre as well as proteins. Mangoes are economically important for Mozambique because of suitable climatic conditions and international market opportunities. This study compared morphological and AFLP characterisation of 30 mango varieties from the Umbeluzi research station, including some commercial varieties: “Keitt”, “Kent”, “Haden”, “Sensation” and “Ruby”. Morphological characterisation using IPGRI descriptors were divided into quantitative (23 characteristics) and qualitative (58 characteristics) data. The total variation was lower using quantitative (89.4% similarity) than qualitative data (60% similarity). The combined quantitative and qualitative dendrogram had 63% similarity and clustered varieties in three subgroups based on high fruit weight, high Brix content and low fruit weight. AFLP characterisation used seven primer combinations, generating 207 data points and detecting 74.9% polymorphism with an average of 30 fragments per primer combination. The total variation was low (72.49% similarity) and the dendrogram showed two main groups subdivided in five subgroups based on low fruit weight, dwarfness and low Brix content, high fruit weight and roundish fruit shape. The combined morphological and AFLP dendrogram was more accurate in clustering varieties based on geographic origin within the country and from outside. The dendrograms presented in the study will help breeders to select parents for crosses. PCA results confirmed the pattern of clustering of varieties based on fruit weight and Brix/acidity ratio. It is recommended to extend the study to include, the entire collection at Umbeluzi and to include morphological data, considering pest and diseases resistance characterisation, as well as genetic and cytological analysis. A study of genotype x environment interactions done over years should be undertaken in future.Afrikaans: Veselperske (Mangifera indica L.) behoort aan die familie Anacardiaceae. Verbruik
het wêreldwyd toegeneem as gevolg van die voedingswaarde; veselperskes is ryk aan
Vitamien A en C, kalsium, β-karoteen, vesel en proteïene. Die gewas is vir
Mosambiek ekonomies belangrik omdat die land geskikte klimaatstoestande vir die
gewas het en daar internasionale markgeleenthede bestaan. Die studie vergelyk
morfologiese en AFLP analises van 30 variëteite afkomstig van die Umbeluzi
navorsingsstasie. Kommersiële variëteite: “Keitt”, “Kent”, “Haden”, “Sensation” en
“Ruby” was ook ingesluit by die studie. Vir die beskrywing van morfologiese
eienskappe is IPGRI beskrywers gebruik en die eienskappe is verdeel in
kwantitatiewe (23 eienskappe) en kwalitatiewe (58 eienskappe) data. Die totale
variasie vir die kwantitatiewe data (89.4%) was meer ooreenstemmend as variasie vir
die kwalitatiewe data (60%). Die gekombineerde kwalitatiewe en kwantitatiewe
dendrogram het 63% ooreenstemmendheid gehad en die variëteite groepeer in drie
subgroepe gebaseer op hoë vrugmassa, hoë Brix inhoud en lae vrugmassa. AFLP
merkers met sewe priemstuk-kombinasies is gebruik om data punte te genereer en
74.9% polymorfismes is bepaal met 'n gemiddeld van 30 fragmente per priemstukkombinasie.
Die totale variasie was laag (72.49%) en die dendrogram toon twee hoof
groepe wat in vyf subgroepe verdeel is op grond van lae vrugmassa, dwergagtigheid
en lae Brix waarde, hoë vrugmassa en ronde vrugvorm. Die gekombineerde
morfologiese en AFLP dendrogram was meer akkuraat in groepering van variëteite
gebaseer op geografiese oorsprong binne en buite die land. Die dendrogramme in die
studie sal telers help om die geskikste ouers vir kruisings te kies. PCA resultate
bevestig die groeperings patroon gebaseer op vrugmassa en Brix/suur verhouding. Dit
word aanbeveel dat die studie uitgebou word om al die inskrywings in die Umbeluzi
versameling te ondersoek en dat morfologiese data vir peste en siekte weerstand as
ook sitologie daarby ingesluit word. 'n Studie oor jare om die genotipe x omgewing
interaksie te bepaal moet in die toekoms onderneem word
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Enviromental influence on the expression of wheat protein fractions under South African drylands conditions
No full textEnglish: Ten South African hard red wheat cultivars (BettaDN, Caledon, Elands, Gariep, Komati, Limpopo, Matlabas, PAN3118, PAN3349 and PAN3377) were planted at five localities over two seasons in the winter dryland wheat production area of South Africa. Localities were divided into North Western Free State (NW-FS) and Eastern Free State (E-FS). Size-exclusion high-performance liquid-chromatography was applied to determine the molecular weight distribution of SDS-extractable protein and SDS-unextractable protein fractions. Relative and absolute amounts were measured for glutenin, gliadin, albumin and globulin.
Protein fractions did not increase parallel to increased flour protein content. The gliadin fraction showed the highest correlation in NW-FS, while polymeric proteins showed the highest correlation in E-FS with flour protein content. Albumin and globulin showed the lowest correlation with flour protein content in both regions. Environment made the largest contribution to variation in flour protein content in both regions.
Bread making properties were correlated with flour protein content and protein fractions. Significant positive correlations were observed between flour protein content and wet gluten content, farinograph water absorption, alveograph extensibility, alveograph strength and loaf volume. Significant negative correlations occurred between flour protein content and SDS-sedimentation and alveograph tenacity. Mixograph peak time was mainly influenced by genotype and did not correlate significantly with flour protein content, while unextractable polymeric proteins showed a significant positive correlation with mixograph peak time. Partial correlations were conducted to remove the quantitative effect of flour protein content. Polymeric and monomeric protein fractions affected bread making quality differently in NW-FS than E-FS, indicating the effect of environment on protein composition.
Pearson’s correlation showed that flour protein content correlated between significantly and not significantly with alveograph tenacity, alveograph extensibility and mixogrpah peak time MPT for individual cultivars. The stepwise multiple linear regression indicated that flour protein content could only explain variation in alveograph extensibility and loaf volume for two cultivars in E-FS. Protein fractions contributed in different degrees to variation for alveograph tenacity, alveograph extensibility, mixograph peak time and loaf volume for individual cultivars and between the two regions. The model explained a larger percentage of variation in alveograph extensibility for BettaDN, Caledon, Elands, Gariep, Komati and Limpopo in E-FS than in NW-FS, while the model explained a larger proportion of variation in mixograph peak time for Matlabas and the Pannar cultivars in NW-FS than in E-FS. Albumin and globulin fractions contributed more to variation for alveograph tenacity, alveograph extensibility and mixograph peak time in NW-FS than in E-FS. The effect of albumin and globulin on baking quality justifies further research.
Environment had a large influence on flour protein content and percentages of protein fractions. Protein fractions affected baking quality differently between environments and genotypes.Afrikaans: Tien Suid Afrikaanse harde rooi koringkultivars (BettaDN, Caledon, Elands, Gariep, Komati, Limpopo, Matlabas, PAN3118, PAN3349 en PAN3377) is aangeplant oor vyf lokaliteite en twee seisoene, in die winter droëland koringproduksie streek van Suid Afrika. Lokaliteite was verdeel in Noordwes-Vrystaat (NW-VS) en Oos-Vrystaat (O-VS). Molekulêre gewig verspreiding van SDS-oplosbare en SDS-nie-oplosbare proteïenfraksies is bepaal met hoë uitset vloeistofchromatografie. Relatiewe en absolute hoeveelhede is bepaal vir glutenien, gliadien, albumien en globulien.
Proteïenfraksies het nie parallel met meel proteïeninhoud vermeerder nie. Gliadiene het die hoogste korrelasie met meel proteïeninhoud getoon in NW-VS, terwyl polimeriese proteïene die hoogste korrelasie getoon het in O-VS. Albumien en globulien het die laagste korrelasie getoon met meel proteïeninhoud. Omgewing het die grootste bydrae gemaak tot variasie in meel proteïeninhoud in beide streke.
Korrelasies is bepaal tussen meel proteïeninhoud en proteïenfraksies met bakkwaliteit eienskappe. Betekenisvolle positiewe korrelasies is waargeneem tussen meel proteïeninhoud en nat gluten inhoud, farinograaf waterabsorpsie, alveograaf rekbaarheid, alveograaf sterkte en broodvolume. Betekenisvolle negatiewe korrelasies het voorgekom tussen meel proteïeninhoud en SDS-sedimentasie en alveograaf weerstand teen uitrekking. Miksograaf mengtyd was hoofsaaklik deur die genotipe beïnvloed en het nie ‘n betekenisvolle korrelasie met meel proteïeninhoud getoon nie, terwyl nie-oplosbare polimeriese proteïene ‘n betekenisvolle positiewe korrelasie met miksograaf mengtyd getoon het. Gedeeltelike korrelasies is ook uitgevoer, waar die kwantitatiewe effek van meel proteïeninhoud verwyder word. Polimeriese en monomeriese proteïenfraksies beïnvloed kwaliteitseienskappe verskillend in NW-VS teenoor die O-VS, wat dui op die invloed van die omgewing op proteïensamestelling.
Meel proteïeninhoud vir individuele kultivars se korrelasies het gewissel tussen betekenisvol en nie-betekenisvol met alveograaf weerstand teen uitrekking, alveograaf
rekbaarheid en miksograaf mengtyd. Stapsgewyse veelvuldige liniêre regressie het aangedui dat meel proteïeninhoud alleen, variasie in alveograaf rekbaarheid en broodvolume slegs vir twee kultivars in O-VS kon verklaar. Proteïenfraksies het verskillend bygedra tot variasie in alveograaf weerstand tot uitrekking, miksograaf mengtyd en broodvolume vir individuele kultivars en tussen die twee streke. Die model kon ‘n groter persentasie van variasie verklaar in alveograaf rekbaarheid vir BettaDN, Caledon, Elands, Gariep, Komati en Limpopo in O-VS teenoor NW-VS, terwyl die model ‘n groter persentasie van variasie in miksograaf mengtyd in Matlabas en die Pannar kultivars verklaar in NW-VS teenoor O-VS. Albumien en globulien fraksies het ‘n groter bydrae gemaak tot variasie in alveograaf weerstand tot uitrekking, alveograaf rekbaarheid en miksograaf mengtyd in NW-VS teenoor O-VS. Die effek van albumien en globulien op eienskappe vir bakkwaliteit regverdig verdere navorsing.
Omgewing het ‘n groot invloed op meel proteïeninhoud en hoeveelhede van proteïenfraksies gehad. Die invloed van proteïenfraksies op eienskappe vir bakkwaliteit het verskil tussen genotipes en omgewings. Verskillende genotipes en omgewings mag verskillende resultate oplewer
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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