The objective of this thesis is to better understand the impact of paper and printer types on xerographic print quality. To achieve this objective, commercially printed samples comprising of ten different paper substrates printed using three different xerographic printers were examined. The print quality of these samples was assessed in terms of print microgloss and its nonuniformity, print density, print and gloss mottle, print roughness, and visual ranking. This study showed that print mottle conducted by Fast Fourier Transform produced the best correlation with visual ranking at the size range of 0.1 - 1mm, while print gloss mottle was found to affect print quality regardless of the mottle size. Brightness, opacity, basis weight, gloss 75, and roughness of these paper substrates were found to have the most significant effect on print quality. All of the optical properties of paper included in this analysis showed a strong correlation to print quality.

There are high demands on flexographic print quality to be sufficiently high and consistent in order to create a competitive packaging. At the same time the production efficiency need to be high. Printers thus need to achieve the same quality every time and quickly start-up new printing jobs. To accomplish this, one needs to gain a thorough understanding of how the liquid packaging board interacts with the ink and impacts the print quality. This thesis focuses on water-based ink absorption of liquid packaging boards and particularly on a) how uniformity of ink absorption can be measured and b) to what extent the absorption characteristics contribute to print mottle in flexographic printing. The work encompasses two parts. First, an absorption non-uniformity test method has been developed using a staining technique. This method is unique as it measures how unevenly an aqueous solution is absorbed, in a short time period and without impact from surface roughness. Moreover, the contributions from white-top mottle and absorption non-uniformity can be quantified simultaneously from one single measurement. Second, a method to independently study the effects of absorption non-uniformity on print quality has been established. This is achieved by introducing artificial absorption non-uniformities with well-controlled barrier patterns. A barrier pattern may modify local pore structure and/or surface energy, hence lead to lateral absorption variations. By these means, it is possible to produce a substrate property-matrix; encompassing absorption non-uniformity and for example surface roughness. It was demonstrated that non-uniform absorption indeed has a negative impact on print quality, both on smoother and rougher boards. Low absorption made print density decrease and uneven absorption caused print mottle. This was the case when other properties of the samples were kept within a narrow range; otherwise surface roughness appeared to determine print mottle ranking.

What is meant with print quality, what makes people perceive the quality of an image in a certain way? An inquiry was made about what the parameters are that strongly affect the perception of digital printed images. A subjective test and some measurements make the basis for the thesis. The goal was to find a tool to predict perceived image quality when investigating the connections between the subjective test and the measurements. Some suitable images were chosen, with a variety of motifs. A test panel consisting of people that are used to observe image quality answered questions about the perception of the quality. Measurements were made on a special test form to get information about the six different printers used in the investigation. One of the discoveries was made when two images with the same colorful motif were compared. The first image got a much higher grade for general quality than the second image, even though the second image was printed with a printer that had a larger color gamut. The reason of this is that the first image consists of more saturated colors, and the second image has more details. The human eye perceives the more saturated image to be better than the image with more details. Another discovery was the correlation between the perceived general quality of a colored image and the perceived color gamut. One conclusion was that a great difference between two calculated color gamuts resulted in a large difference in perception of the color gamuts. A discovery of an image with very few colors and many glossy surfaces was that print mottle and sharpness are strictly connected to the general quality.

Coated solid bleached board belongs to the top-segment of paperboards. One important property of paperboard is the printability. In this diploma work a specific print defect, oriented mottle, has been studied in association with Iggesund Paperboard. The objectives of the work were to develop a method for analysis of the dark and light areas of oriented mottle, to analyse these areas, and to clarify the effect from the print, coating and paperboard surface related factors. This would clarify the origin of oriented mottle and predict oriented mottle on unprinted paperboard. The objectives were fulfilled by analysing the areas between the dark halftone dots, the amount of coating and the ink penetration, the micro roughness and the topography. The analysis of the areas between the dark halftone dots was performed on several samples and the results were compared regarding different properties. The other methods were only applied on a limited selection of samples. The results from the study showed that the intensity differences between the dark halftone dots were enhanced in the dark areas, the coating amount was lower in the dark areas and the ink did not penetrate into the paperboard. The other results showed that areas with high transmission corresponded to dark areas, smoother micro roughness, lower coating amount and high topography. A combination of the information from these properties might be used to predict oriented mottle. The oriented mottle is probably an optical phenomenon in half tone prints, and originates from variations in the coating and other paperboard properties.

Tryckflammighet, ojämnheter på tryckta ytor är en icke önskvärd egenskap som länge bekymrat tryckeribranschen. Ojämnheterna har medfört en försämrad kvalité på kartongmaterial som visuellt får materialet att se fläckig och sämre ut. Egenskapen har visat sig vara mer tydlig på ytor som tryckts med färgen cyan, vanligt förekommande i metoderna flexotryck och offsettryck. Detta examensarbete har gjorts hos ett företag inom tryckeribranschen. Företaget har använt två metoder för bedömning av tryckflammighet på tryckta vätske- och förpackningskartong, en Parvis visuell bedömning och en instrumentell mätning med en skanner och programvaran STFI Mottling Expert. Programvaran har utvecklats med syftet att på ett identiskt sätt bedöma bland annat tryckflammighet på kartongmaterialytor så som den upplevs på den visuella bedömningen. Under en lång period har företaget använt instrumentet för att verifiera resultat som erhålls från den visuella metoden. Under de senaste åren har korrelationen mellan dessa metoder blivit sämre, till en punkt där företaget inte litar på instrumentet. Korrelationsanalys har därför utförts för att undersöka sambandet mellan dessa två metoder och orsaken till problemet. I samband med detta har företaget upptäckt en möjlighet, att undersöka topografiska egenskaper på otryckt material från samma produktionstillfälle och dess korrelation med tryckflammigheten. Topografiska värden har därför tagits fram via instrumentet L&W OptiTopo samt programvaran RISE OptiTopo Expert och korrelationsanalys utförts. Resultaten indikerar en fortfarande väldigt hög korrelation mellan de två metoder som används för bedömning av tryckflammighet, dock inom andra våglängder än den rekommenderad av programvaran och orsakerna till tidigare problem har lagts fram. Topografiska värden som ytråhet samt andelen kratrar under en viss tröskel har kunnat kopplas till tryckflammighetsvärdet och sambandet visats. / Print mottle, unevenness on printed surfaces is an undesirable property that has long worried the printing industry. The effect has led to a degraded quality in cartonboard which visually makes the material look stained and worse. The property has been shown to be more evident on surfaces printed with the color cyan, commonly in printing methods such as flexography and offset. This project degree has been conducted at a company in the printing industry. The company has used two methods for assessing print mottle on printed liquid- and packaging board, a Pairwise visual assessment and an instrumental measurement with a scanner and software STFI Mottling Expert. The software has been developed with the purpose of identifying among others print mottle on cartonboard surfaces in an identical way as the visual assessment. For a long period of time, the company has used the instrument to verify the results from the visual assessment. In recent years, the correlation between these methods has gotten worse, to a point where company does not trust the instrument. Correlation analysis has therefore been performed to investigate the relationship between these two methods and the cause of the problem. In connection with this, the company has discovered an opportunity, to investigate topographical properties on unprinted materials from the same production line and its correlation with print mottle. Topographical values have therefore been determined using the L&W OptiTopo instrument and RISE OptiTopo Expert software. The results indicate that there is still a very high correlation between the two methods used to assess print mottle, though within wavelengths other than the one recommended by the software and the causes of previous problems have been presented. Topographical values such as surface roughness and the proportion of craters under a certain threshold have been linked to the print mottle value and the correlation between them shown.

The bean leaf beetle (BLB), Cerotoma trifurcata (Forster) (Coleoptera: Chrysomelidae), is a pest of commercially produced legumes in eastern Virginia. Field cage and manual-defoliation studies were conducted in Virginia to determine an economic impact of BLB. In the manual-defoliation study, snap bean plants had significant yield loss when > 25% of leaf area was removed. In the field cage experiments, I was unable to establish beetle densities per plant to impact yield. Host plant selection by BLB was done in laboratory and field studies with snap bean, lima bean, and soybeans. Laboratory studies showed that BLB preferred snap bean and lima bean over soybean. Field studies did not showed no preference. A survey was conducted on the Eastern Shore of Virginia determine the epicenter of BPMV. Soybean leaves and beetles were collected and assessed for BPMV by ELISA or TBIA. Beetles at the ESAREC were BPMV-positive upon emergence from overwintering sites, but the virus load was low when tested by ELISA. This suggests acquisition of virus from a source other than infected cultivated legumes. To find the potential inoculum sources of BPMV in eastern Virginia, leguminous weeds and perennial weeds were tested for BPMV. Four weed species gave BPMV-positive tissue blots including: Oxalis stricta, Rumex acetosella, Trifolium pretense, and Trifolium repens. Insecticidal seed treatment of thiamethoxam on soybean seeds was evaluated to test the efficacy. Leaf area eaten and beetle mortality was measured. The thiamethoxam seed treatment protected soybean seedlings from beetle feeding through the V2 stage of growth. / Master of Science in Life Sciences

Bean pod mottle virus (BPMV), a member of the genus Comovirus in the family Comoviridae, is widespread in the major soybean-growing areas in the United States. The complete nucleotide sequences of the genomic RNAs of the naturally occurring partial diploid strain IL-Cb1 were determined. Intermolecular RNA1 recombinants were isolated from strain IL-Cb1 and characterized at the molecular level. Structurally similar recombinant RNA1 was also generated after four passages in soybean derived from plants previously inoculated with a mixture of infectious RNA1 transcripts from two distinct strains. BPMV was developed as a plant viral vector that is appropriate for gene expression and virus-induced gene silencing (VIGS) in soybean. The foreign gene was inserted between the movement protein (MP) and the large coat protein (L-CP) coding regions. The recombinant BPMV constructs were stable following several serial passages in soybean and relatively high levels of protein expression were attained. Successful expression of several proteins with different biological activities was demonstrated from the BPMV vector. Double infection of soybean by BPMV and SMV triggers a synergistic interaction leading to a serious disease. To investigate the underlying mechanism, helper componentprotease (HC-Pro) genes from several SMV strains and TEV were expressed from BPMV vectors. The recombinant BPMV vectors carrying the HC-Pro genes from SMV strain G7 or TEV induced very severe symptoms on soybean whereas constructs containing the HC-Pro gene from SMV isolate P10, a mild strain with an apparent defect in synergism, induced only very mild symptoms. Transient agroinfiltration assays using GFP-transgenic Nicotiana benthamiana showed that HC-Pro from SMV isolate P10 was not a RNA silencing suppressor, whereas those of SMV strain G7 and TEV exhibited strong suppressor activities. Analysis of chimeric HC-Pro genes and point mutations indicated that a positively charged amino acid at position 144 is critical for the suppressor function of not only SMV HC-Pro but also other potyvirus HC-Pro proteins. Although amino acid substitution at position 144 resulted in changes in small RNA profile, it did not affect HC-Pro stability.

Este trabalho apresenta resultados da caracterização biológica, serológica e molecular de um potyvirus que causa mosqueado foliar em maracujazeiro e infecta, experimentalmente, plantas de abobrinha-de-moita (Cucurbita pepo cv. Caserta). Esse potyvirus foi inicialmente observado em extratos de folhas de maracujazeiro e em cortes ultra finos de tecidos infectados de abobrinha-de-moita, em microscopia eletrônica. Além de partículas alongadas, observaram-se inclusões lamelares do tipo catavento, características de espécies de vírus do gênero Potyvirus. Após purificação a partir de folhas de maracujazeiro com mosqueado, as partículas desse potyvirus foram dissociadas para a caracterização dos seus principais componentes. O RNA viral apresentou peso molecular de aproximadamente 10000 pb. O peso molecular da proteína da capa protéica foi de aproximadamente 32 kDa. Antissoro policlonal produzido em coelho reagiu com o antígeno homólogo, bem como com o Passion fruit woodiness virus (PWV), em teste de PTA-ELISA, mas não reagiu com dois potyvirus que infectam cucurbitáceas, Papaya ringspot virus - type W e Zucchini yellow mosaic virus. O antissoro contra o PWV reagiu com o potyvirus do mosqueado do maracujazeiro. Quando três isolados do potyvirus do mosqueado do maracujazeiro (M1, M2 e M3) foram inoculados em 37 espécies vegetais, juntamente com dois isolados do PWV (PWV-1 e PWV-2), constatou-se que todas as espécies infectadas pelos isolados do PWV também o foram com os isolados do potyvirus do mosqueado. Estes últimos, entretanto, também foram capazes de infectar sistemicamente plantas de abobrinha-de-moita cv. Caserta e de abóbora híbrida do tipo Tetsukabuto, o que não ocorreu com os isolados do PWV. Testes de transmissão do isolado M1 do potyvirus do mosqueado, por meio mecânico e com os afídeos Myzus persicae e Aphis gossypii, de plantas de maracujazeiro, abobrinha-de-moita, feijoeiro BT 2 e crotalária, para plantas das mesmas espécies foram positivos. No entanto, observou-se que a eficiência de transmissão foi influenciada pela planta fonte de inóculo. Quando a abobrinha-de-moita foi utilizada como fonte de inóculo, a transmissão só ocorreu para plantas-teste dessa espécie, independente do processo de inoculação. Testes de proteção entre os isolados do potyvirus do mosqueado e do PWV, em plantas de Crotalaria juncea, juntamente com a análise da seqüência de nucleotídeos do gene da capa protéica e da região terminal 3' não traduzida dos isolados M2 e M3, indicaram que o potyvirus do mosqueado é uma estirpe do PWV que ocorre em São Paulo. Análises moleculares comparativas com outras espécies de Potyvirus indicaram que tanto os isolados do potyvirus do mosqueado como os isolados do PWV têm alta identidade com o Cowpea aphid-borne mosaic virus (CABMV). Esse resultado corrobora relato anterior feito no país e aponta para a necessidade de uma alteração na nomenclatura da espécie do vírus que está freqüentemente associada ao endurecimento dos frutos do maracujazeiro no Brasil. / This work presents results of the biological, serological and molecular characterization of a potyvirus that causes leaf mottling on passion fruit and infects some cucurbit plants experimentally. This potyvirus was initially observed in extracts of passion fruit leaves and in ultra thin sections of infected tissue of Cucurbita pepo L. cv. Caserta, examined in the electronic microscope. Besides flexuous filamentous particles, lamellar inclusions, characteristic of species of potyvirus, were observed in infected tissue. After purification from infected passion fruit leaves, virus particles were dissociated for the molecular characterization of their main components. The viral RNA showed a molecular weight of approximately 10000 bp. The molecular weight of the coat protein was nearly 32 kDa. Policlonal antibody, produced in rabbit, reacted with the homologous antigen, as well as with Passion fruit woodiness virus (PWV), in PTA-ELISA. No reaction was observed with Papaya ringspot virus - type W and Zucchini yellow mosaic virus, two potyviruses usually found infecting plants in the Cucurbitaceae family. The antibody against PWV reacted with the passion fruit mottling potyvirus. When three isolates of the passion fruit leaf mottling potyvirus (M1, M2 and M3) and two isolates of PWV were separately inoculated in 37 vegetable species, it was verified that all the species infected with the PWV isolates were also infected with the isolates of the passion fruit leaf mottling potyvirus. Isolates M1, M2 and M3, however, were also capable to infect systemically plants of zucchini squash cv. Caserta and hybrid squash Tetsukabuto, which were not infected with the PWV isolates. Transmission tests showed that the M1 isolate of passion fruit leaf mottling potyvirus was efficiently transmitted from infected plants of passion fruit, zucchini squash, Phaseolus vulgaris cv. BT 2 and Crotalaria juncea to plants of the same species by means of mechanical inoculation. Efficient transmission was also obtained when the aphids Myzus persicae and Aphis gossypii were used as vectors. However, the transmission efficiency was influenced by the plant source of inoculum. When zucchini squash was used as a source of inoculum, the transmission only occurred for plants of the same specie, independent of the method of inoculation. Cross protection tests with isolates of the passion fruit leaf mottling potyvirus and PWV, in plants of C. juncea, together with the analysis of the nucleotide sequences of the coat protein (CP) gene and the 3' non translated region (NTR) of the isolates M2 and M3, indicated that the leaf mottling potyvirus has high identity with the PWV present in São Paulo State. As compared with other species of the genus Potyvirus, isolates of both potyviruses showed high identity with the CP gene and 3' NTR of Cowpea aphid-borne mosaic virus (CABMV). This result corroborates previous report regarding to the identity between Brazilian PWV isolates and CABMV and it points for the need of an alteration in the nomenclature of the virus species frequently associated to passion fruit woodiness in Brazil.

This thesis is about modelling and predicting the perceived whiteness of plain paper from the paper composition, including fluorescent whitening agents. This involves psychophysical modelling of perceived whiteness from measurable light reflectance properties, and physical modelling of light scattering and fluorescence from the paper composition. Existing models are first tested and improvements are suggested and evaluated. A colour appearance model including simultaneous contrast effects (CIECAM02-m2), earlier tested on coloured surfaces, is successfully applied to perceived whiteness. An extension of the Kubelka-Munk light scattering model including fluorescence for turbid media of finite thickness is successfully tested for the first time on real papers. It is extended to layered constructions with different layer optical properties and modified to enable parameter estimation with conventional d/0° spectrophotometers used in the paper industry. Lateral light scattering is studied to enable simulating the spatially resolved radiance factor from layered constructions, and angle-resolved radiance factor simulations are performed to study angular variation of whiteness. It is shown that the linear CIE whiteness equation fails to predict the perceived whiteness of highly white papers with distinct bluish tint. This equation is applicable only in a defined region of the colour space, a condition that is shown to be not fulfilled by many commercial office papers, although they appear white to most observers. The proposed non-linear whiteness equations give to these papers a whiteness value that correlates with their perceived whiteness, while application of the CIE whiteness equation outside its region of validity overestimates perceived whiteness. It is shown that the fluorescence efficiency of FWA is essentially dependent only on the ability of the FWA to absorb light in its absorption band. Increased FWA concentration leads accordingly to increased whiteness. However, since FWA absorbs light in the violet-blue region of the electromagnetic spectrum, the reflectance factor decreases in that region with increasing FWA amount. This violet-blue absorption tends to give a greener shade to the paper and explains most of the observed greening and whiteness saturation at larger FWA concentrations. A red-ward shift of the quantum efficiency is observed with increasing FWA concentration, but this is shown to have a negligible effect on the whiteness value. The results are directly applicable to industrial applications for better instrumental measurement of whiteness and thereby optimising the use of FWA with the goal to improve the perceived whiteness. / PaperOpt

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-10-05T13:00:31Z No. of bitstreams: 1 texto completo.pdf: 1661309 bytes, checksum: d6a61a932643ca508865fd68cbc3df7d (MD5) / Made available in DSpace on 2016-10-05T13:00:31Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1661309 bytes, checksum: d6a61a932643ca508865fd68cbc3df7d (MD5) Previous issue date: 2003-02-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Espécies do gênero Begomovirus (família Geminiviridae) encontradas no hemisfério ocidental tem tipicamente um genoma bissegmentado que consiste em dois componentes genômicos de 2,6 Kb, denominados DNA-A e DNA-B. Atualmente, a grande diversidade de begomovírus patogênicos identificados tem sido explicada pela alta frequência de eventos de recombinação. Relatos adicionais também tem evidenciado a importância dos eventos de recombinação inter-espécies na evolução dos begomovírus e na sua emergência como patógenos relevantes na agricultura. Utilizando-se um programa computacional para detecção de recombinação foram observados eventos de recombinação estatisticamente significantes entre as sequências completas do componente DNA-A de begomovíus que infectam tomateiros, recentemente identificados no Brasil. As progênies recombinantes exibiram diferentes propriedades biológicas e propriedades patológicas aumentadas quando comparadas com os seus prováveis predecessores. O DNA-A de Tomato chlolorotic mottle virus ToCMV-[MG-Bt1], de Minas Gerais, da região de Betim, identificado e clonado por nosso grupo, possui um genoma híbrido no qual o módulo compatível de replicação (AC1 e a origem de replicação) foi provavelmente doado por ToCMV-[BA-Se1] e as sequências remanescentes parecem ter sido originadas de Tomato rugose mosaic virus (ToRMV). Apesar do alto grau de conservação de sequência com os seus predecessores, ToCMV-[MG-Bt1] difere significantemente nas suas propriedades biológicas. De fato, ToCMV-[MG-Bt1] infectou seu hospedeiro natural Lycopersicon esculentum, induziu sintomas atenuados e acumulou DNA viral nas folhas apicais na ausência de um DNA-B cognato. Foi caracterizada a patogenicidade deste DNA-A clonado e infeccioso através de uma gama de hospedeiros, e a efetividade foi avaliada via inclusão de um DNA-B compatível em ensaios de infectividade. O DNA-A de ToCMV-[MG-Bt1] sozinho é capaz de infectar sistematicamente e causar sintomas nos hospedeiros permissíveis Nicotiana benthamiana, Chenopodium amaranticolor e Chenopodium quinoa. Ele move-se sistematicamente em Datura stramonium, mas causa uma infecção assintomática. O acúmulo do DNA viral nas plantas infectadas foi confirmado por PCR. A inclusão de um componente B compatível nos ensaios de infectividade não alterou a sintomatologia das doenças mediadas pelo ToCMV-[MG- Bt1]-A, também não aumentou o nível do DNA-A nos hospedeiros permissíveis. Assim, os resultados deste trabalho forneceram evidências adicionais sobre os eventos de recombinação inter-espécies que podem desempenhar um papel significativo na diversidade dos geminivírus e na sua emergência como patógenos importantes na agricultura. / Species of Begomovirus genus (Geminiviridae family) found in the Western Hemisphere typically have a bipartite genome that consists of two 2.6-kb DNA genomic components, DNA-A and DNA-B. A current consensus prediction for the extent of begomovirus diversity holds that a high frequency of recombination resulted in the recent emergence of highly pathogenic virus genotypes causing a variety of serious begomovirus diseases. We have provided further evidence for the importance of interspecies recombination in begomovirus evolution and emergence as agriculturally relevant pathogens. Using the Recombination Detection Program software, we detected statistically significant recombination events among full-length DNA-A component sequences of recently identified tomato-infecting begomovirus from Brazil. The recombinant progenies exhibited different biological and enhanced pathological properties as compared to their probable predecessors. The Tomato chlolorotic mottle virus ToCMV-[MG-Bt1] DNA-A, identified and cloned by our group, possesses a hybrid genome on which the replication compatible module (AC1 and replication origin) was likely donated by ToCMV-[BA-Se1] and the remaining sequences appear to have originated from Tomato rugose mosaic virus (ToRMV). Despite the high degree of sequence conservation with its predecessors, ToCMV- [MG-Bt1] differs significantly in its biological properties. In fact, ToCMV-[MG-Bt1] DNA-A infected its natural host Lycopersicon esculentum, induced mild symptoms and accumulated viral DNA in the apical leaves in the absence of a cognate DNA-B. We have further characterized the pathogenesis of this infectious cloned DNA-A by determining its host range properties and the effectiveness of inclusion of a compatible DNA-B component in the infectivity assays. ToCMV-[MG-Bt1] DNA-A is able to infect systemically and cause symptoms in the permissive hosts Nicotiana benthamiana, Chenopodium amaranticolor and Chenopodium .quinoa. It moves systemically in Datura stramonium, but causes an asymptomatic infection. The accumulation of viral DNA in the infected plants was confirmed by PCR. Inclusion of a compatible DNA-B component in the infectivity assay did not alter the symptomatology of ToCMV-[MG-Bt1] DNA-A-mediated disease, nor did it increases the DNA-A level in a permissive host. Our results further support the notion that interspecies recombination may play a significant role in geminivirus diversity and emergence as agriculturally important pathogens. / Dissertação importada do Alexandria