Invasive plants: representativeness of research from tropical countries in the global context

Biological invasions threaten the native biota of several countries and this threat is even greater in the tropical regions that have the greatest biodiversity. In order to evaluate the representativeness of studies on invasive plants in tropical countries compared to the world, as well as the region of origin and habits of the most reported invasive plants in research, we analyzed the publications from eight of the most important international journals that address the theme, from January 1995 to December 2004. The articles on biological invasions were classified as theoretical or as case studies, and according to their approach, main question, where the study was conducted, region of origin and habit of the invasive plant. Case studies predominated, as did questions about the environment`s susceptibility to the invasion, the species` invasive power and the impacts it had. The most reported invasive species were herbaceous plants from Asia and Europe. Few articles address tropical environments and only one referred to Brazil. Most referred to North America and Europe. This small number of publications in the tropics indicates the need for a global projection on this subject and underscores the lack of consistent and organized data to understand the phenomenon and propose effective strategies to combat biological invasion.

Nitrosyl ethylenediaminetetraacetate ruthenium(II) complex promotes cellular growth and could be used as nitric oxide donor in plants

Over recent years nitric oxide (NO) not only has appeared as an important endogenous signaling molecule in plants and as a mediator in many developmental and physiological processes, but has also received recognition as a plant hormone. The impressive recent achievements in elucidating the role of NO in plants have come about by the application of NO donors. The aim herein was to study the effects of the different NO donors, sodium nitroprusside (SNP) and the nitrosyl ethylenediaminetetraacetate ruthenium(II) ([Ru(NO)(Hedta)]) complex on cellular growth in embryogenic suspension cultures of Araucaria angustifolia. Appraisal of our data revealed that [Ru(NO)(Hedta)] stimulated about 60% of cellular growth in embryogenic suspension cultures of A. angustifolia, with results similar to those observed with the SNP donor. Nevertheless, application of the NO scavenger PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) inhibited this cellular growth in both. Cellular growth was correlated with an increase in endogenous NO levels after 21 days of culture, especially in treatments with NO donors. Our results demonstrated that the [Ru(NO)Hedta] complex could possibly be used as a NO donor in plants. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Evaluation of Fungal Burden and Aflatoxin Presence in Packed Medicinal Plants Treated by Gamma Radiation

This study was developed to evaluate the fungal burden, toxigenic molds, and mycotoxin contamination and to verify the effects of gamma radiation in four kinds of medicinal plants stored before and after 30 days of irradiation treatment. Eighty samples of medicinal plants (Peumus boldus, Camellia sinensis, Maytenus ilicifolia. and Cassia angustifolia) purchased from drugstores, wholesale, and open-air markets in Sao Paulo city, Brazil, were analyzed. The samples were treated using a (60)Co gamma ray source (Gammacell) with doses of 5 and 10 kGy. Nonirradiated samples were used as controls of fungal isolates. For enumeration of fungi on medicinal plants, serial dilutions of the samples were plated in duplicate onto dichloran 18% glycerol agar. The control samples revealed a high burden of molds, including toxigenic fungi. The process of gamma radiation was effective in reducing the number of CFU per gram in all irradiated samples of medicinal plants after 30 days of storage, using a dose of 10 kGy and maintaining samples in a protective package. No aflatoxins were detected. Gamma radiation treatment can be used as an effective method for preventing fungal deterioration of medicinal plants subject to long-term storage.

The effect of sixteen medicinal plants used in the Brazilian pharmacopoeia on the expression and activity of glutathione S-transferase in hepatocytes and leukemia cells

Glutathione S-transferase (GST) is a family of enzymes involved in the detoxification of electrophilic compounds. Different classes of GST are expressed in various organs, such as liver, lungs, stomach and others. Expression of GST can be modulated by diet components and plant-derived compounds. The importance of controlling GST expression is twofold: increasing levels of GST are beneficial to prevent deleterious effects of toxic and carcinogenic compounds, while inhibition of GST in tumor cells may help overcoming tumor resistance to chemotherapy. A screening of 16 plants used in the Brazilian pharmacopoeia tested their effects on GST expression in hepatocytes and Jurkat (leukemia) T-cells. The methanol extracts of five plants inhibited GST expression in hepatocytes. Three plants significantly inhibited and four others induced GST expression in Jurkat cells. Among these, the extracts of Bauhinia forficata Link. (Leguminosae) and Cecropia pachystachya Trec. (Urticaceae) inhibited GST expression at relatively low concentrations. With the exception of B. forficata, all plants were cytotoxic when administered to Jurkat cells at high doses (1 mg/mL) and some extracts were considerably cytotoxic even at lower concentrations.

Detection of citrus canker in citrus plants using laser induced fluorescence spectroscopy

Citrus canker is a serious disease caused by Xanthomonas citri subsp. citri bacteria, which infects citrus plants (Citrus spp.) leading to a large economic loss in citrus production worldwide. In Brazil citrus canker control is done by an official eradication campaign, therefore early detection of such disease is important to prevent greater economic losses. However, detection is difficult and so far it has been done by visual inspection of each tree. Suspicious leaves from citrus plants in the field are sent to the laboratory to confirm the infection by laboratory analysis, which is a time consuming. Our goal was to develop a new optical technique to detect and diagnose citrus canker in citrus plants with a portable field spectrometer unit. In this paper, we review two experiments on laser induced fluorescence spectroscopy (LIF) applied to detect citrus canker. We also present new data to show that the length of time a leaf has been detached is an important variable in our studies. Our results show that LIF has the potential to be applied to citrus plants.

INSECT CHYMOTRYPSINS: CHLOROMETHYL KETONE INACTIVATION AND SUBSTRATE SPECIFICITY RELATIVE TO POSSIBLE COEVOLUTIONAL ADAPTATION OF INSECTS AND PLANTS

Insect digestive chymotrypsins are present in a large variety of insect orders but their substrate specificity still remains unclear. Ewer insect chymotrypsins from 3 different insect orders (Dictyoptera, Coleoptera and two Lepidoptera) were isolated using affinity chromatography. Enzymes presented molecular masses in the range of 20 to 31 kDa and pH optima in the range of 7.5 to 10.0. Kinetic characterization. using different, colorimetric and fluorescent substrates indicated that insect chymotrypsins differ from, bovine chymotrypsin in their primary specificity toward small substrates (like N-benzoyl-L-Tyr p-nitroanilide) rather than on their preference for large substrates (exemplified by Succynil-Ala-Ala-Pro-Phe P-nitroanilide). Chloromethyl ketones (TPCK, N-alpha-tosyl-L-Phe chloromethyl ketone and Z-GGF-CK, N-carbobenzoxy-Gly-Gly-phe-CK) inactivated all chymotrypsins legated. Inactivation rates follow apparent first-order kinetics with variable second order rates (TPCK, 42 to 130 M(-1)s(-1); Z-GGF-CK, 150 to 450 M(-1)s(-1) that may be remarkably low for S. frugiperda chymotrypsin (TPCK, 6 M(-1)s(-1); Z-GGF-CK, 6.1 M(-1) s(-1)). Homology modelling and sequence alignment showed that. in lepidopteran chymotrypsins, differences in the amino acid residues in the neighborhood of the catalytic His 57 may affect its pKa, value. This is Proposed as the cause of the decrease in His 57 reactivity toward chloromethyl ketones. Such amino acid replacement in the active site is proposed. to be an adaptation to the presence of dietary ketones. (C) 2009 Wiley Periodicals, Inc.

Proteomic analysis reveals suppression of bark chitinases and proteinase inhibitors in citrus plants affected by the citrus sudden death disease

Citrus sudden death (CSD) is a disease of unknown etiology that greatly affects sweet oranges grafted on Rangpur lime rootstock, the most important rootstock in Brazilian citriculture. We performed a proteomic analysis to generate information related to this plant pathogen interaction. Protein profiles from healthy, CSD-affected and CSD-tolerant stem barks, were generated using two-dimensional gel electrophoresis. The protein spots were well distributed over a pI range of 3.26 to 9.97 and a molecular weight (MW) range from 7.1 to 120 kDa. The patterns of expressed proteins on 2-DE gels made it possible to distinguish healthy barks from CSD-affected barks. Protein spots with MW around 30 kDa and pI values ranging from 4.5 to 5.2 were down-regulated in the CSD-affected rootstock bark. This set of protein spots was identified as chitinases. Another set of proteins, ranging in pI from 6.1 to 9.6 with an MW of about 20 kDa, were also suppressed in CSD-affected rootstock bark; these were identified as miraculin-like proteins, potential trypsin inhibitors. Downregulation of chitinases and proteinase inhibitors in CSD-affected plants is relevant since chitinases are well-known pathogenesis-related protein, and their activity against plant pathogens is largely accepted.

Understanding Wax Printing: A Simple Micropatterning Process for Paper-Based Microfluidics

This technical note describes a detailed study on wax printing, a simple and inexpensive method for fabricating microfluidic devices in paper using a commercially available printer and hot plate. The printer prints patterns of solid wax on the surface of the paper, and the hot plate melts the wax so that it penetrates the full thickness of the paper. This process creates complete hydrophobic barriers in paper that define hydrophilic channels, fluid reservoirs, and reaction zones. The design of each device was based on a simple equation that accounts for the spreading of molten wax in paper.

Offset Lithography

A group of students are shown working in the Offset Lithography Department at the New York Trade School. Several presses can be seen in the room. Black and white photograph.

Utredning om huruvida Dalarnas Tidningars produktion passar en KBA Cortina

This degree project illustrates newsprint and waterless offset. A new news press was introduced at Drupa-00, Cortina from KBA, which is the first news press dedicated the waterless technique. With actual statistics from the company in question an investigation was made whether their production fits this press. It came out in the investigation that the production of the company, from statistics, fits this press very good. A table was made where different timeschedules were accounted for the new press, with semi- and full automatic plate changing for present and to be added papers. The waterless technology is compared to conventional offset with the difference that the plate is based on a sort of laminatetechnology. Like conventional plates this plate has a base made of aluminium. Lightsensitive photopolymer isunited as a layer or coat on top of the aluminium and a 2µm thin oleophobic siliconlayer is applied on top of the photopolymer. Considering the print, the waterless method has a higher qualitygrade than conventional offset. No water is emulsifiedin the ink, and therefore the printed dot gets a higher density. The loss of dampening solution and higher tack of the ink gives sharper dots. This makes the colourspace bigger why a greater range of colours can be printed. The loss of dampening solution gives a more stable dotgain, which contributes to that a higher screen can be used. The disadvantage is that the plate can't do as many rotations as the conventional plate. A waterless plate makes around 100 000-500 000 rotations before it needs to be removed owing to type- and manufacturer of the plate. The plate is also slightly more sensitive and expensive than conventional plates, around 1,4 - 1,7 × aluminium printing plates. A waterless system can be installed in a conventional printing press by degrees and when large editions are being printed a cooler needs to be installed in the oscillationrollers of the press, since an increase in temperature can make the oleophobic parts of the plate oleophilic. The Cortina is however equipped with a temperature controlsystem at the beginning. To avoid picking, caused by the tacky ink, a blanket with a high “quick release” should be used.

Ink-Jet Printing of Color Optical Filters for LCD Applications

At the age of multi-media, portable electronic devices such as mobile phones, personal digital assistant and handheld gaming systems have increased the demand for high performance displays with low cost production. Inkjet printing color optical filters (COF) for LCD applications seem to be an interesting alternative to decrease the production costs. The advantage of inkjet printing technology is to be fast, accurate, easy to run and cheaper than other technologies. In this master thesis work, we used various disciplines such as optical microscopy, rheology, inkjet printing, profilometering and colorimetry. The specific aim of the thesis was to investigate the feasibility of using company-A pigment formulation in inkjet production of COF for active matrix LCD applications. Ideal viscosity parameters were determined from 10 to 20mPa·s for easy inkjet printing at room temperature. The red pigments used are fully dispersed into the solvent and present an excellent homogenous repartition after printing. Thickness investigations revealed that the printed COF were equal or slightly thicker than typically manufactured ones. The colorimetry investigations demonstrated color coordinates very close to the NTSC red standard. LED backlighting seems to be a valuable solution to combine with the printed COF regarding to the spectrum and color analysis. The results on this thesis will increase the understanding of inkjet printing company-A pigments to produce COF for LCD applications.

Utvärdering av digitala provtryckssystem

Six different Digital Proofing Systems from three different techniques have been evaluated as totechnique, printing quality, economy and usability. Digital proof from two paper qualities, coatedand uncoated, has been compared with references printed in offset, to see how good they match eachother. Only two Proofing Systems manage to print on reference paper. The other Proofing Systemsuse special paper for digital proof.Measurements and visuell judgement show that the Digital Proofing Systems visualise referencepictures with quite good quality. Proof optimised for coated paper visualise the colours with goodresult. Proof optimised for uncoated paper shows higher quality than the references, which depends onthe surface of the proofing paper. Comparison between reference paper and proofing paper has takenplace as to differences in colour and paper quality.The Digital Proofing Systems are fully automatic, which demand a quite comprised education forcorrect handling. The purchase price and printing costs vary considerably between the ProofingSystems.

Troubleshooting med avseende på avsättningar på gummiduk, Bobergs tryckeri AB

Bobergs printing house in Falun has during some time had problems regarding deposits on blankets intheirs Müller Martini UV-printing presses. Deposits appear in both image areas and non-image areas.These areas have been analyzed and the deposits on non-image areas contain chalk, clay and talc. Thequestion remains how these material bond to the blanket surface. The chalk and clay comes from thepaper. The talc comes from the ink. Deposits from image areas contain pigment and talc from the printingink. The dampening water has also been analyzed. The result shows some sort of problem with thehardness regulator for the clean water. The pH-level should be increased a few steps.

Introduktion till Certifierad Grafisk Produktion på Jernström Offset

The aim for this thesis was to develop a proposal of documentation, containing rules and procedures, which JernströmOffset needs to acquire the Certified Graphic Production certification. A fundamental part was to study the materialissued by Sveriges Grafiska Mediaförening, to clarify the requirements that must be met to obtain the certification. Therecommendations found in the CGP material must also be considered.Based on the requirements and recommendations of Certified Graphic Production, a mapping of the workflows atJernström Offset was performed. It was done by interviewing employees from different departments at the company,this to get a clear understanding of the operations carried out throughout the production flow and the final qualityfollow-up.During our reviewing process we found that a number of changes, in terms of working environment and practices,must be made at the company. As a result of this we propose some appropriate actions to be implemented.The documentation was finally written, through the requirements and recommendations of Certified GraphicProduction and then applied to Jernström Offset’s work procedures.

Printing colour hard proofs using EFI Colorproof XF v. 3.1 and Photoshop CS3, and production substrates.

EFI Colorproof XF was found to be more convenient from a user’s aspect, and had features which are covered in the ISO 12647-7 standard (e.g. the ability to simulate screening and print margin information), which Photoshop CS3 lacked. None of the proofing systems distinguished itself in a clear way from the other; sometimes, on certain substrates, Photoshop CS3 produced most accurate colours, sometimes EFI Colorproof XF did. Further investigations need to be carried out to tell more exactly which system produce most accurate colours. Only 6 out of 34 simulation-combinations had colours within the tolerances in the standard. The result also shows that the production substrates should not be used as proofing substrates. Instead the proofing papers especially made for ink jet should be used to obtain more colour-accurate prints.