Histochemical and ultrastructural study of Caesalpinia peltophoroides Benth. (Leguminosae-Caesalpinoideae) seeds

The objective of this work was to correlate data on light microscopy observations through histochemical analysis and polarized light techniques and investigations in transmission electron microscopy (TEM) to characterize the reserve materials in C. peltophoroides Benth. (Leguminosae-Caesalpinoideae) cotyledons, popularly known as "sibipiruna", a tropical tree species with wide distribution in Brazil. The cotyledon mesophyll, especially in the abaxial face, is rich in unsaturated neutral lipids contained in numerous lipid bodies dispersed in the cytoplasm. Proteins, more concentrated in the adaxial face of the cotyledons, occur in all the mesophyll and are stored in protein bodies containing globoids, with variable number and size, responsible for accumulation of mineral reserves. Calcium oxalate druses have distribution restricted to the cotyledons adaxial face and are associated with protein bodies. Starch, also distributed all over the cotyledon mesophyll, occurs in small amounts in plastids with developed lamellar system. Secretory cavities rich in phenolic compounds occur among procambial strands.

Physiological and biochemical characterization of the assai palm (Euterpe oleracea Mart.) during seed germination and seedling growth under aerobic and anaerobic conditions

Physiological and biochemical aspects of assai palm during seed germination and early seedling growth were investigated. Seeds collected from plants growing in flooded and upland forests were used to determine the influence of normoxic (aerobic) and anoxic (anaerobic) conditions in germination and the initial and average time of development in the roots and shoots. After 75 days, seedlings germinated under normoxia were transferred to trays and submitted to flooding. Seed reserves (lipids, proteins, soluble sugars and starch) were monitored for quiescent and germinated seeds maintained under normoxic and anoxic conditions, as well as after 5, 10 and 20 days of seedling growth. Alcohol dehydrogenase (ADH) activity was quantified in roots and leaves of seedlings without or with flooding (partial and total). Seeds were not able to germinate under anoxia. Different strategies of storage mobilization of lipids, proteins, soluble sugars and starch were observed in seeds of each environment. ADH activity was induced by anoxia, with the highest level observed in the leaves. This study showed that, under normoxic conditions, the best developmental performance of assai palm seeds, from flooded or upland forest areas, during germination was associated with primary metabolites mobilization and seedling flooding tolerance with increased ADH activity. We conclude that the assai palm is well adapted to the anoxic conditions provoked by flooding.

Optimization of the refining and shoe press in board production

Optimointi on tavallinen toimenpide esimerkiksi prosessin muuttamisen tai uusimisen jälkeen. Optimoinnilla pyritään etsimään vaikkapa tiettyjen laatuominaisuuksien kannalta paras tapa ajaa prosessia tai erinäisiä prosessin osia. Tämän työn tarkoituksena oli investoinnin jälkeen optimoida neljä muuttujaa, erään runkoon menevän massan jauhatus ja määrä, märkäpuristus sekä spray –tärkin määrä, kolmen laatuominaisuuden, palstautumislujuuden, geometrisen taivutusjäykkyyden ja sileyden, suhteen. Työtä varten tehtiin viisi tehdasmittakaavaista koeajoa. Ensimmäisessä koeajossa oli tarkoitus lisätä vettä tai spray –tärkkiä kolmikerroskartongin toiseen kerrosten rajapintaan, toisessa koeajossa muutettiin, jo aiemmin mainitun runkoon menevän massan jauhatusta ja jauhinkombinaatioita. Ensimmäisessä koeajossa tutkittiin palstautumislujuuden, toisessa koeajossa muiden lujuusominaisuuksien kehittymistä. Kolmannessa koeajossa tutkittiin erään runkoon menevän massan jauhatuksen ja määrän sekä kenkäpuristimen viivapaineen muutoksen vaikutusta palstautumislujuuteen, geometriseen taivutusjäykkyyteen sekä sileyteen. Neljännessä koeajossa yritettiin toistaa edellisen koeajon paras piste ja parametreja hieman muuttamalla saada aikaan vieläkin paremmat laatuominaisuudet. Myös tässä kokeessa tutkittiin muuttujien vaikutusta palstautumislujuuteen, geometriseen taivutusjäykkyyteen ja sileyteen. Viimeisen kokeen tarkoituksena oli tutkia samaisen runkoon menevän massan vähentämisen vaikutusta palstautumislujuuteen. Erinäisistä vastoinkäymisistä johtuen, koeajoista saadut tulokset jäivät melko laihoiksi. Kokeista kävi kuitenkin ilmi, että lujuusominaisuudet eivät parantuneet, vaikka jauhatusta jatkettiin. Lujuusominaisuuksien kehittymisen kannalta turha jauhatus pystyttiin siis jättämään pois ja näin säästämään energiaa sekä säästymään pitkälle viedyn jauhatuksen mahdollisesti aiheuttamilta muilta ongelmilta. Vähemmällä jauhatuksella ominaissärmäkuorma saatiin myös pidettyä alle tehtaalla halutun tason. Puuttuvat lujuusominaisuudet täytyy saavuttaa muilla keinoin.

Physical-chemical characterization and wet milling yield of four maize hybrids

The influence of physical-chemical characteristics of maize grains and lactic acid concentrations on byproduct yields, generated by conventional wet milling, was studied during steeping, for four maize hybrids and two lactic acid concentrations (0.55 and 1.00%). For physical-chemical characterization, grain dimensions (length, thickness, and width) were determined, as well as mass of 100 grains, percentage of floating grains, volumetric mass, and centesimal composition. Statistical differences were found for percentage of floating grains (2.33 to 24.67%), volumetric mass (0.814 to 0.850 kg.L-1), mass of 100 grains (0.033 to 0.037 kg), water content (11.86 to 12.20%), proteins (8.21 to 9.06%), lipids (3.00 to 4.77%), and ashes (1.07 to 1.26%). There were no relationships of wet milling yields with maize appearance and physical-chemical characteristics. The addition of 1.00% lactic acid did not statistically improve byproduct yields; however, it favored separation of the grain components.

Microencapsulation of pequi pulp by spray drying: use of modified starches as encapsulating agent

The aim of this study was to evaluate the microencapsulation of pequi pulp by spray drying. A central composite rotational design was used in order to evaluate the effect of the independent variables: inlet air temperature, surfactant concentration and modified starch concentration. The dependent variables were assumed as yield of the process and the product features microencapsulated. A selection of the best process condition was performed to obtain the best condition of a product with the highest vitamin C and carotenoids content. Powders showed moisture content below 2%. The experimental values of hygroscopicity, yield, water activity, total carotenoids and vitamin C powders ranged from 7.96 to 10.67 g of adsorbed water/100g of solids, 24.34 to 49.80%, 0.13 to 0.30, 145.78 to 292.11 mg of ascorbic acid/g of pequi solids and 15.51 to 123.42 mg of carotenoids/g of pequi solids, respectively. The inlet air temperature 140°C, the surfactant concentration of 2.5% and the modified starch concentration of 22.5% was recommended as the selected condition. By the scanning electron microscopy, it was observed that most of the particles had spherical shape and smooth surface.

Chemical attributes of soil and dry mass accumulation of maize fertilized with cassava wastewater

The aim of this study was to evaluate chemical attributes alterations of a clay-loam textured soil and dry mass accumulation of maize submitted to application of cassava wastewater doses in three assessment periods. The experiment was conducted under greenhouse using a completely randomized experimental design in a factorial 5 × 3, with four replicates. The analyzed factors of research were doses of cassava wastewater (0; 12.6; 25.2; 50.4; 75.6 m3 ha-1) andassessment periods (20, 40 and 52 days after germination). The following parameters were determined: electric conductivity of soil saturation extract, pH in water, content of available P, content of exchangeable K+, Ca2+, Mg2+ and Na+of soil, dry mass of leaves and stem. The application of cassava wastewater on soil enables increase of pH, electric conductivity of saturation extract, contents of available P, contents of exchangeable K+ and Na+ and dry mass of leaves and stem. However, only pH and content of exchangeable K+ of soil, the electric conductivity of saturation extract and dry mass of leaves and stem are influenced by assessment period.

Effect of cycle time and airflow in biological nitrogen removal from poultry slaughterhouse wastewater using sequencing batch reactor

This study aimed to evaluate the influence of airflow (0.25, 0.50 and 0.75 L.L-1.min-1) and cycle time (10.45 h, 14.25 h and 17.35 h) on a sequencing batch reactor (SBR) performance in promoting nitrification and denitrification of poultry slaughterhouse wastewater. The operational stages included feeding, aerobic and anoxic reactions, sedimentation and discharge. SBR was operated in a laboratory scale with a working volume of 4 L, keeping 25% of biomass retained inside the reactor as inoculum for the next batch. In the anoxic stage, C: N ratio was maintained between 5 and 6 by adding cassava starch wastewater. A factorial design (22) with five repetitions was designed at the central point to evaluate the influence of cycle time and airflow on total inorganic nitrogen removal (N-NH4++N-NO2-+N-NO3-) and in the whole process (nitrification and denitrification). The highest total inorganic nitrogen removal (93.3%) was observed for airflow of 0.25 L.L-1.min‑1 and a cycle time of 14.25 h. At the end of the experiment, the sludge inside the reactor was characterized by fluorescent in situ hybridization (FISH), indicating the presence of ammonia and nitrite oxidizing bacteria.

Hydrogen production from cassava processing wastewater in an anaerobic fixed bed reactor with bamboo as a support material

Attempting to associate waste treatment to the production of clean and renewable energy, this research sought to evaluate the biological production of hydrogen using wastewater from the cassava starch treatment industry, generated during the processes of extraction and purification of starch. This experiment was carried out in a continuous anaerobic reactor with a working volume of 3L, with bamboo stems as the support medium. The system was operated at a temperature of 36°C, an initial pH of 6.0 and under variations of organic load. The highest rate of hydrogen production, of 1.1 L.d-1.L-1, was obtained with application of an organic loading rate of 35 g.L-1.d-1, in terms of total sugar content and hydraulic retention time of 3h, with a prevalence of butyric and acetic acids as final products of the fermentation process. Low C/N ratios contributed to the excessive growth of the biomass, causing a reduction of up to 35% in hydrogen production, low percentages of H2 and high concentrations of CO2in the biogas.

‘Sweet grape’ tomato post harvest packaging

ABSTRACT This paper aims at evaluating the shelf life of mini tomatoes (Lycopersicum esculentum Mill.) cultivar ‘Sweet Grape’, grown in hydroponics, and stored under environmental and refrigerated conditions inside different packages. We adopted a completely randomized design, in which treatments were combinations of storage conditions: environment (e) and refrigerated (r) with packaging: polyvinyl chloride film (PVC); low-density polyethylene (LDPE); biofilm of tomato fruit of Solanum lycocarpum A.St.-Hil (lobeira) (TFB); cassava starch biofilm (CSB); carnauba wax (Copernicia prunifera) (CW), and without packaging - control (C). Physicochemical and sensory tests were carried out at the beginning (day zero), and at 8, 19, and 33 days of storage (DS). Fruit stored inside PVCr, LDPEe, LDPEr, and CWr had an acceptable shelf life of 33 days. The use of cassava and tomato starches were not effective in controlling fruit fresh weight loss. ‘Sweet Grape’ tomato postharvest conservation was enhanced under refrigerated conditions. The sensory evaluation results revealed that CWr treatment most pleased appraisers, while PCV had the highest rejection rate.

Täyteainepitoisuuden ja retentioainesysteemin optimointi

Työssä tutkittiin tarrapaperikoneen pohjapaperin täyteainepitoisuuden nostamisen vaikutusta koneen ajettavuuteen ja paperin ominaisuuksiin. Työn tavoitteena oli löytää ne prosessitekniset keinot, joilla voitaisiin saavuttaa raskaiden pintapapereiden tavoitetuhkatasot. Lisäksi pyrittiin optimoimaan retentioaineiden annokset ja ajotavat korkeilla tuhkatasoilla. Kirjallisuusosassa tarkasteltiin pinta- ja kolloidikemian perusteita sekä täyteainepitoisuuden vaikutusta paperin ominaisuuksiin ja prosessoitavuuteen. Lisäk-si syvennyttiin märänpään kemiaan selvittämällä mm. kalsiumkarbonaatin vesiliuoskemiaa ja erilaisten retentioaineiden ominaisuuksia ja niiden reaktiomekanismeja. Työn kokeellinen osa koostui kahdesta koeajosta. Ensimmäisessä koeajossa selvitettiin täyteainesaostumien muodostumismekanismeja ja paperikoneen ajettavuutta täyteainepitoisuutta nostettaessa yli raskaiden pintapapereiden tavoitetasojen. Saadut tulokset osoittivat, että märänpään kemiantila pysyi koeajon aikana muuttumattomana eikä mitään saostumien muodostumista havaittu. Täyteainepitoisuudessa päästiin 3 % yli lajikohtaisen tuhkatavoitteen ilman ajettavuusongelmia. Toisessa koeajossa keskityttiin erityisesti märänpään retentioaineiden määrien optimointiin ja paperin laatuominaisuuksiin. Koeajossa täyteainepitoisuutta nostettiin yli tavoitetasojen. Saadut tulokset osoittivat, että täyteainepitoisuuden nostolla ei ollut vaikutusta paperin laatuun tai paperikoneen ajettavuuteen. Massatärkkelyksen avulla pystyttiin korvaamaan kationisen polymeerin retentiovaste ja kompensoimaan täyteainepitoisuuden noston myötä tullut paperin lujuuksien lasku. Koeajoissa ja prosessin seurannassa tuli ilmi myös useita eri tekijöitä, joilla oli vaikutusta retentioon, retentioaineiden tehoon ja prosessin stabiilisuuteen. Tehdyistä yksittäisistä havainnoista on hyötyä pyrittäessä ymmärtämään märänpään prosessin tilaa ja sen vaikutusta paperikoneen ajettavuuteen. Työ saavutti sille asetetut tavoitteet ja sen ansiosta paperikoneen märänpään raaka-aineiden ja kemikaalien syöttösuhteita pystyttiin muuttamaan tavalla, joka vähensi paperinvalmistuksen kustannuksia ilman että paperin laatuominaisuudet huononivat.

Gelatin as an additive in bio-based barrier films

The main objective of the present study was to verify the approach on starch-gelatin blending for the paperboard coating formulations with enhanced barrier and mechanical properties. Based on that, another objective was to find out, how the approach will function with wood-based polysaccharides (CMC, EHEC and HPC) by analyzing their barrier properties and convertibility. The last objective was to find out, if pigments can be used in the composition of polysaccharide-protein blends without causing any negative effect on stated properties. The whole process chain of the barrier coating development was studied in the research. The methodology applied included pilot-scale coating and converting trials for the evaluation of mechanical properties of obtained coatings, namely their exposure to cracking with the loss of barrier properties. The results obtained indicated that the combination of starch with gelatin, in fact, improves the grease barrier properties and flexibility of starch-based coatings, thereby confirming the offered approach. The similar results were obtained for CMC, exhibited elevated barrier properties and surface coverage, proving that the approach also functions with wood-based polysaccharides. The introduction of equal amounts of talc gave various effects at different gelatin dosages on barrier properties of wood-based polysaccharides. Mainly, the elevation of grease barrier properties was observed. The convertibility of talc-filled coatings was not sufficient.

Täyteaineen ja tärkkelyksen annostelun optimointi paperikoneen lyhyeen kiertoon

Diplomityön tavoitteena oli selvittää tärkkelyksen ja täyteaineen annostelupaikkojen sekä – tapojen vaikutukset SC- heatset web offset -paperin ominaisuuksiin ja pintalujuuteen. Lisäksi selvitettiin, muuttuuko paperin pölyäminen annostelupaikkojen tai – tapojen vaikutuksesta. Diplomityön kirjallisuusosiossa käsiteltiin heatset web offset -painokoneen rakennetta ja sen toimintaa. Lisäksi käsiteltiin heatset web offset -painokoneella ilmenevät pölyongelmien tyypit ja, mitkä eri paperin tekijät vaikuttavat heatset web offset -painokoneen pölyämisongelmiin. Lisäksi kirjallisuusosiossa käsiteltiin yleisimmät pintalujuutta parantavat kemikaalit sekä näiden kemikaalien annostelupaikat paperikoneen lyhyeen kiertoon. Alkutason määrityksessä ja ensimmäisessä koeajossa havaittiin, että paperin huokoisuus ja huokosrakenne olivat tärkeimmät SC heatset web offset -paperin pintalujuuteen vaikuttavat tekijät. KCL:n HSWO–koepainokoneella painetuista rullista annostelutapa 4, jossa tärkkelystä ja täyteainetta annosteltiin perälaatikon syöttöpumpun imupuolelle perinteisesti, oli pintalujuudeltaan kestävin. Ahmatti-kokeissa havaittiin, että tärkkelyksen ja täyteaineen annostelu TrumpJet- laitteistolla lähempänä paperikoneen perälaatikkoa, annostelutapa 6, pienentää rullan sisäistä vetolujuushajontaa. Ahmatti -pilotkokeissa havaittiin myös, että paperin lujuusominaisuudet ja vetolujuushajonnat voitiin säilyttää entisellään, kun tärkkelystä ja täyteainetta annosteltiin perinteisesti perälaatikon syöttöpumpun imupuolelta. Toisesta koeajon koepainorullasta havaittiin KCL:n koepainatuksissa, että paperin pintalujuus heikentyy annosteltaessa tärkkelystä 8 kg/t verrattuna 10 kg/t tärkkelysannosteluun. Näiden tapojen ero ei ole merkittävä.

Functional Genomic Approaches for Deciphering Plant-Virus Interactions

Plant-virus interactions are very complex in nature and lead to disease and symptom formation by causing various physiological, metabolic and developmental changes in the host plants. These interactions are mainly the outcomes of viral hijacking of host components to complete their infection cycles and of host defensive responses to restrict the viral infections. Viral genomes contain only a small number of genes often encoding for multifunctional proteins, and all are essential in establishing a viral infection. Thus, it is important to understand the specific roles of individual viral genes and their contribution to the viral life cycles. Among the most important viral proteins are the suppressors of RNA silencing (VSRs). These proteins function to suppress host defenses mediated by RNA silencing and can also serve in other functions, e.g. in viral movement, transactivation of host genes, virus replication and protein processing. Thus these proteins are likely to have a significant impact on host physiology and metabolism. In the present study, I have examined the plant-virus interactions and the effects of three different VSRs on host physiology and gene expression levels by microarray analysis of transgenic plants that express these VSR genes. I also studied the gene expression changes related to the expression of the whole genome of Tobacco mosaic virus (TMV) in transgenic tobacco plants. Expression of the VSR genes in the transgenic tobacco plants causes significant changes in the gene expression profiles. HC-Pro gene derived from the Potyvirus Y (PVY) causes alteration of 748 and 332 transcripts, AC2 gene derived from the African cassava mosaic virus (ACMV) causes alteration of 1118 and 251transcripts, and P25 gene derived from the Potyvirus X (PVX) causes alterations of 1355 and 64 transcripts in leaves and flowers, respectively. All three VSRs cause similar up-regulation in defense, hormonally regulated and different stress-related genes and down-regulation in the photosynthesis and starch metabolism related genes. They also induce alterations that are specific to each viral VSR. The phenotype and transcriptome alterations of the HC-Pro expressing transgenic plants are similar to those observed in some Potyvirus-infected plants. The plants show increased protein degradation, which may be due to the HC-Pro cysteine endopeptidase and thioredoxin activities. The AC2-expressing transgenic plants show a similar phenotype and gene expression pattern as HC-Pro-expressing plants, but also alter pathways related to jasmonic acid, ethylene and retrograde signaling. In the P25 expressing transgenic plants, high numbers of genes (total of 1355) were up-regulated in the leaves, compared to a very low number of down-regulated genes (total of 5). Despite of strong induction of the transcripts, only mild growth reduction and no other distinct phenotype was observed in these plants. As an example of whole virus interactions with its host, I also studied gene expression changes caused by Tobacco mosaic virus (TMV) in tobacco host in three different conditions, i.e. in transgenic plants that are first resistant to the virus, and then become susceptible to it and in wild type plants naturally infected with this virus. The microarray analysis revealed up and down-regulation of 1362 and 1422 transcripts in the TMV resistant young transgenic plants, and up and down-regulation of a total of 1150 and 1200 transcripts, respectively, in the older plants, after the resistance break. Natural TMV infections in wild type plants caused up-regulation of 550 transcripts and down-regulation of 480 transcripts. 124 up-regulated and 29 down-regulated transcripts were commonly altered between young and old TMV transgenic plants, and only 6 up-regulated and none of the down-regulated transcripts were commonly altered in all three plants. During the resistant stage, the strong down-regulation in translation-related transcripts (total of 750 genes) was observed. Additionally, transcripts related to the hormones, protein degradation and defense pathways, cell division and stress were distinctly altered. All these alterations may contribute to the TMV resistance in the young transgenic plants, and the resistance may also be related to RNA silencing, despite of the low viral abundance and lack of viral siRNAs or TMV methylation activity in the plants.

Brittleness of Paper

Brittleness is a well-known material characteristic but brittleness of paper is vaguely covered. The objective of this thesis was to characterize the phenomenon and causes around brittleness of paper and to clarify if it is a measurable property. Brittleness of paper was approached from the perspectives of paper physics and paper mills. Brittleness is a property of dry paper and it causes problems at the finishing stages of paper machine. According to paper physics, brittle materials fail in the elastic regime, while ductile materials can locally accumulate a plastic deformation prior to the fracture and they are often able to withstand higher stresses. Brittleness of paper is vastly affected by the surrounding conditions: paper as a hygroscopic material tries to get to the equilibrium. It is also affected by the quality of the pulp used. Measurement techniques can be divided into two categories: based on the viscoelastic behavior of paper and on the exposure to the mechanical stress of sort. The experimental part of the thesis was based on the trials with brittle and non-brittle mill-made LWC papers. It is divided into three parts: strength testing of the brittle and non-brittle papers, analysis of the conditions that may contribute the brittleness and the experimental methods to evaluate brittle behavior. The strength measurements confirmed the influence of the moisture content, but only tensile energy absorption and the fracture toughness measurements provided modest differences between the brittle and non-brittle papers. Versatile analysis of the possible contributing factors resulted into speculation, while the brittle papers contained higher amount of starch, triglycerides and steryl esters. The experimental research proved that the formation, the sensory impression and the variation of local strains may contain the crucial information of paper brittleness.

Weed interference periods in the 'Fécula Branca' cassava

This study aimed to determine the periods of weed interference in the first cycle of 'Fécula Branca' cassava. The experiment was arranged in a randomized block design, with four repetitions. The treatments consisted of eight periods of weed control (25, 50, 75, 100, 125, 150, and 175 days after planting - DAP) and eight periods of coexistence between the weed community and the crop (25, 50, 75, 100, 125, 150, and 175), besides control without weeds and control with weeds until harvest (322 DAP). The predominant weed species with higher relative importance were: Avena sativa, Sorghum halepense, Conyza Canadensis, Euphorbia heterophylla, Raphanus raphanistrum, and Commelina benghalensis. It was concluded that, accepting losses of 1% for root and starch production, the period before interference (PBI) was 66 and 70 DAP; the total period of interference prevention (TPIP) was 88 and 91 DAP and the critical period of interference (CPI) was between 66-88 and 70-91 DAP, respectively. For losses of 5% for root and starch production, the PBI was 87 and 88 DAP, and the TPIP 80 and 81 DAP, respectively; in this case, there was no CPI. Considering the average prices of R$ 218.90 t-1 and R$ 1,191.84 t-1, paid in 2012 for root and starch production, respectively, and control cost of R$ 300.00 ha-1 , the root and starch production for the period prior to economic loss (WEEPPEL) could be estimated to be 20 and 24 DAP, respectively.