Efeito de subdoses de 2,4-D na produtividade de fumo e suscetibilidade da cultura em função de seu estádio de desenvolvimento

O presente trabalho teve como objetivo determinar os efeitos de subdoses do herbicida 2,4-D na cultura do fumo. Os experimentos foram conduzidos a campo durante o ano de 2003, no município de Santa Isabel do Ivaí - PR, utilizando-se de fumo tipo Virgínia. No primeiro experimento, foram aplicadas, no estádio de pré-florescimento, doses de 0,84; 1,68; 3,36; 6,72; 13,44 e 26,88 g e.a. ha-1 de 2,4-D, equivalentes à deriva de 0,125; 0,25; 0,5; 1,0; 2,0 e 4,0% de produtos comerciais aplicados a 1,0 L ha-1 (670 g e.a. ha-1). Para o segundo experimento, os tratamentos foram constituídos pela combinação em esquema fatorial de duas doses (6,72 e 13,44 g e.a. ha-1, equivalentes a 1,0 e 2,0% de deriva) e três épocas de aplicação após o transplante para o campo. Nenhum sintoma visual marcante de fitotoxicidade foi observado dentro da faixa de doses avaliada. Visualmente, alguns dos possíveis efeitos atribuídos à fitotoxicidade ocasionada pela deriva de 2,4-D na cultura do fumo podem estar associados à utilização de antibrotantes. Nenhuma das doses aplicadas no primeiro experimento afetou a produtividade da cultura, nem o aspecto e qualidade das folhas, tendo o fumo tolerado até 4,0% de deriva avaliada. Resultados obtidos no segundo experimento confirmaram esses dados, constatando-se que níveis de deriva de até 2,0% (13,44 g e.a. ha-1), aplicados em três fases após o transplante das mudas para o campo, não causaram qualquer efeito negativo sobre a produtividade da cultura.

Efeito de subdoses de 2,4-D na produtividade de uva itália e suscetibilidade da cultura em função de seu estádio de desenvolvimento

Durante os anos agrícolas de 2002-2003 e 2003-2004 foram conduzidos trabalhos no município de Maringá - PR, com o objetivo de avaliar o dano potencial de subdoses de 2,4-D sobre plantas de uva, imitando depósitos decorrentes de deriva. No primeiro experimento, a aplicação foi realizada cerca de 30 dias após a poda de inverno, num pomar de uva Itália. As doses utilizadas foram de 6,72; 13,44; 26,88; 53,76 e 107,52 g de equivalente ácido (e.a.) por hectare de 2,4-D, equivalentes a depósitos de 1,0%; 2,0%; 4,0%; 8,0% e 16,0%, assumindo-se uma aplicação de 1 L ha-1 (670 g e.a. ha-1). Nessa data, as plantas encontravam-se na fase de emissão de cachos e florescimento (estádio 15). O surgimento de sintomas visuais de fitointoxicação foi imediato e proporcional às doses aplicadas. A produtividade da cultura foi afetada por todas as doses aplicadas nesse estádio de crescimento. No entanto, mesmo com as injúrias severas registradas na dose mais alta, as plantas afetadas se recuperaram após duas podas para as condições de manejo regionais (duas safras por ano). No segundo experimento, foram aplicadas doses equivalentes a derivas de 1,0 e 2,0% (6,72 e 13,44 g e.a. ha-1) em três estádios do ciclo de desenvolvimento. A aplicação de doses < 13,44 g e.a. ha-1 (2,0% de deriva simulada) a partir do estádio de "meia-baga", não causou repercussões negativas em termos de injúrias visuais e produtividade.

Variation in nitrogen use strategies and photosynthetic pathways among vascular epiphytes in the Brazilian Central Amazon

The variation in nitrogen use strategies and photosynthetic pathways among vascular epiphyte families was addressed in a white-sand vegetation in the Brazilian Central Amazon. Foliar nitrogen and carbon concentrations and their isotopic composition (δ15N and δ13C, respectively) were measured in epiphytes (Araceae, Bromeliaceae and Orchidaceae) and their host trees. The host tree Aldina heterophylla had higher foliar N concentration and lower C:N ratio (2.1 ± 0.06% and 23.6 ± 0.8) than its dwellers. Tree foliar δ15N differed only from that of the orchids. Comparing the epiphyte families, the aroids had the highest foliar N concentration and lowest C:N ratios (1.4 ± 0.1% and 34.9 ± 4.2, respectively). The orchids had more negative foliar δ15N values (-3.5 ± 0.2‰) than the aroids (-1.9 ± 0.7‰) and the bromeliads (-1.1 ± 0.6‰). Within each family, aroid and orchid taxa differed in relation to foliar N concentrations and C:N ratios, whereas no internal variation was detected within bromeliads. The differences in foliar δ15N observed herein seem to be related to the differential reliance on the available N sources for epiphytes, as well as to the microhabitat quality within the canopy. In relation to epiphyte foliar δ13C, the majority of epiphytes use the water-conserving CAM-pathway (δ13C values around -17‰), commonly associated with plants that live under limited and intermittent water supply. Only the aroids and one orchid taxon indicated the use of C3-pathway (δ13C values around -30‰).

Sequence change in the HS2-LCR and Gg-globin gene promoter region of sickle cell anemia patients

The fetal hemoglobin (HbF) levels and ßS-globin gene haplotypes of 125 sickle cell anemia patients from Brazil were investigated. We sequenced the Gg- and Ag-globin gene promoters and the DNase I-2 hypersensitive sites in the locus control regions (HS2-LCR) of patients with HbF level disparities as compared to their ßS haplotypes. Sixty-four (51.2%) patients had CAR/Ben genotype; 36 (28.8%) Ben/Ben; 18 (14.4%) CAR/CAR; 2 (1.6%) CAR/Atypical; 2 (1.6%) Ben/Cam; 1 (0.8%) CAR/Cam; 1 (0.8%) CAR/Arab-Indian, and 1 (0.8%) Sen/Atypical. The HS2-LCR sequence analyses demonstrated a c.-10.677G>A change in patients with the Ben haplotype and high HbF levels. The Gg gene promoter sequence analyses showed a c.-157T>C substitution shared by all patients, and a c.-222_-225del related to the Cam haplotype. These results identify new polymorphisms in the HS2-LCR and Gg-globin gene promoter. Further studies are required to determine the correlation between HbF synthesis and the clinical profile of sickle cell anemia patients.

Näin opetan lisäävää valmistusta ja 3D-tulostusta: Pohdintoja uuden teknologian opetuksesta ja koulutuksesta

Additive manufacturing (shortened as AM), or more commonly 3D printing, consists of wide variety of different modern manufacturing technologies. AM is based on direct printing of a digital 3D model to a final product which is fabricated adding material layer by layer. This is from where term additive manufacturing has its origin. It is not only material what is added, but it is also value, properties etc. which are added. AM enables production of different and even better products compared to conventional manufacturing technologies. An estimation of potential of additive manufacturing can be gathered by considering the potential of laser cutting, which is one of the most widely used modern manufacturing technologies. This technique has been used over 40 years, and whole market around this technology is at the moment c. four billion euros and yearly growth is around 10 %. One factor affecting this success of laser cutting is that laser cutting enables radical improvements to products made of flat sheet. AM and 3D printing will do the same for three dimensional parts. Laser devices, which are at the moment used in 3D printing, are globally at the moment only around 1% of all laser devices used in any fabrication technology, so even with a cautious estimate the potential growth of at least 100 % is coming in next few years. Role of education is very important, when this kind of modern technology is industrially implemented. When both generation entering to work life and also generation who has been a while in work life understands new technology, its potential and limitations, this is the point when also product design can be rethought Potential of product design is driving force for wide use of additive manufacturing and 3D printing. Utilization of additive manufacturing and 3D printing is also opportunity for Finland and Finnish industry. This technology can save Finnish manufacturing industry. This technique has stron potential, as Finland has traditionally strong industrial know-how and good ICT knowledge.

Actinobacillus pleuropneumoniae induces SJPL cell cycle arrest in G2/M-phase and inhibits porcine reproductive and respiratory syndrome virus replication

Background: Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important pathogens in the swine industry and causes important economic losses. No effective antiviral drugs against it are commercially available. We recently reported that the culture supernatant of Actinobacillus pleuropneumoniae, the porcine pleuropneumonia causative agent, has an antiviral activity in vitro against PRRSV in SJPL cells. Objectives of this study were (i) to identify the mechanism behind the antiviral activity displayed by A. pleuropneumoniae and (ii) to characterize the active molecules present in the bacterial culture supernatant. Methods: Antibody microarray analysis was used in order to point out cellular pathways modulated by the A. pleuropneumoniae supernatant. Subsequent, flow cytometry analysis and cell cycle inhibitors were used to confirm antibody microarray data and to link them to the antiviral activity of the A. pleuropneumoniae supernatant. Finally, A. pleuropneumoniae supernatant characterization was partially achieved using mass spectrometry. Results: Using antibody microarray, we observed modulations in G2/M-phase cell cycle regulation pathway when SJPL cells were treated with A. pleuropneumoniae culture supernatant. These modulations were confirmed by a cell cycle arrest at the G2/M-phase when cells were treated with the A. pleuropneumoniae culture supernatant. Furthermore, two G2/M-phase cell cycle inhibitors demonstrated the ability to inhibit PRRSV infection, indicating a potential key role for PRRSV infection. Finally, mass spectrometry lead to identify two molecules (m/z 515.2 and m/z 663.6) present only in the culture supernatant. Conclusions: We demonstrated for the first time that A. pleuropneumoniae is able to disrupt SJPL cell cycle resulting in inhibitory activity against PRRSV. Furthermore, two putative molecules were identified from the culture supernatant. This study highlighted the cell cycle importance for PRRSV and will allow the development of new prophylactic or therapeutic approaches against PRRSV.

Experimental evidence of the spin-glass transition in the diluted magnetic semiconductor Zn(1-x)Mn(x)In(2)Se(4)

This work reports on magnetic measurements of the quasi-two-dimensional (quasi-2D) system Zn(1-x)Mn(x)In(2)Se(4), with 0.01 <= x <= 1.00. For x > 0.67, the quasi-2D system seems to develop a spin-glass behaviour. Evidence of a true phase transition phenomenon is provided by the steep increase of the nonlinear susceptibility chi(nl) when approaching T(C) from above. The static scaling of chi(nl) data yields critical exponents delta = 4.0 +/- 0.2, phi = 4.37 +/- 0.17 and TC = 3.4 +/- 0.1 K for the sample with x = 1.00 and similar values for the sample with x = 0.87. These critical exponents are in good agreement with values reported for other spin-glass systems with short-range interactions.

Avaliação do extrato do fungo caripia montagnei e de agonistas de PPAR - α no processo inflamatório

The mushrooms have been object of intense research in view of its potential raising of application in different sectors of the pharmacology and alimentary industry. Among diverse bioactive composites of polyssacharides nature that exist in the fungus the glucans are much searched. These are polymers of glucose and classified as the type of glicosidic linking [α, β]. Peroxisome proliferator-activated receptors (PPARs), ranscription factors belonging to the family of nuclear receptors that bind themselves o specific agonists, have shown their importance in controlling the inflammatory process. The aim of this study was to perform a chemical characterization of extract rom the mushroom Caripia montagnei, assess its antiinflammatory and antibacterial effect and determine if this effect occurs via PPAR. This mushroom is composed of carbohydrates (63.3±4.1%), lipids (21.4l±0.9%) and proteins (2.2± 0.3%). The aqueous solution resulting from the fractionation contained carbohydrates (98.7±3.3%) and protein (1.3±0.25%). Analyses of infrared spectrophotometry and of nuclear magnetic esonance demonstrated that the extract of mushroom C. montagnei is rich in β-glucans. In hioglycolate-induced peritonitis, the C. montagnei glucans (50 mg/kg) educed the inflammatory process in 65.5±5.2% and agonists, pharmacological igands, for PPAR: Wy-14643 (49.3±6.1%), PFOA (48.9±3.8%) and clofibrate in 45.2±3.2%. Sodium diclofenac showed a reduction of 81.65±0.6%. In the plantar edema, the glucans from C. montagnei (50 mg/kg) and L-NAME reduced the edema to a similar degree 91.4±0.3% and 92.8±0,5 %, respectively. In all the groups tested, nitric oxide (NO), an inflammation mediator, showed a significant reduction in the nitrate/nitrite levels when compared to the positive control (P<0.001). The C. montagnei glucans did not show cytotoxicity in the concentrations tested (2.5, 5.0, 10.0, 20.0 and 40.0 µg/100 µL). Antibacterial activity demonstrated that, unlike total extract, there was no inhibition of bacterial growth. The C. montagnei glucans show great potential for antiinflammatory applications. This effect suggests that it is mediated by PPAR activation and by COX and iNOS inhibition

Production and characterization of glucoamylase from fungus Aspergillus awamori expressed in yeast Saccharomyces cerevisiae using different carbon sources

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Measurement of the CP-violation parameter of B-0 mixing and decay with p(p)over-bar ->mu mu X data

We measure the dimuon charge asymmetry A in p (p) over bar collisions at a center of mass energy root s=1960 GeV. The data was recorded with the D0 detector and corresponds to an integrated luminosity of approximately 1.0 fb(-1). Assuming that the asymmetry A is due to asymmetric B-0 <->(B) over bar (0) mixing and decay, we extract the CP-violation parameter of B-0 mixing and decay: ((epsilon B0))/(1+vertical bar epsilon B0 vertical bar 2)=(AB0)/(4)= -0.0023 +/- 0.0011(stat)+/- 0.0008(syst).A(B)(0) is the dimuon charge asymmetry from decays of B-0(B) over bar (0) pairs. The general case, with CP violation in both B-0 and B-s(0) systems, is also considered. Finally we obtain the forward-backward asymmetry that quantifies the tendency of mu(+) to go in the proton direction and mu(-) to go in the antiproton direction. The results are consistent with the standard model and constrain new physics.

Influence of agricultural biomass burning on aerosol size distribution and dry deposition in southeastern Brazil

The size distributed composition of ambient aerosols is used to explore seasonal differences in particle chemistry and to show that dry deposition fluxes of soluble species, including important plant nutrients, increase during periods of biomass (sugar cane trash) burning in São Paulo State, Brazil. Measurements were made at a single site centrally located in the State's sugar cane growing region but away from the immediate vicinity of burns, so that the air sampled was representative of the regional background. Calculation of ion equivalent balances showed that during burning periods smaller particles (Aitken and accumulation modes) were more acidic, containing higher concentrations of SO(4)(2-), oxalate, NO(3)(-), HCOO(-), CH(3)COO(-), and Cl(-), but insufficient NH(4)(+) and K(+) to achieve neutrality. Larger particles showed an anion deficit due to the presence of unmeasured ions and comprised resuspended dusts modified by accumulation of nitrate, chloride, and organic anions. Increases of resuspended particles during the burning season were attributed to release of earlier deposits from the surfaces of burning vegetation as well as increased vehicle movement on unsurfaced roads. During winter months the relative contribution of combined emissions from road transport and industry diminished due to increased emissions from biomass combustion and other activities specifically associated with the harvest period. Positive increments in annual particulate dry deposition fluxes due to higher fluxes during the sugar cane harvest were 44.3% (NH(4)(+)), 42.1 % (K(+)), 31.8% (Mg(2+)), 30.4% (HCOO(-)), 12.8% (Cl(-)), 6.6% (CH(3)COO(-)), 5.2% (Ca(2+)), 3.8% (SO(4)(2-)), and 2.3% (NO(3)(-)). Na(+) and oxalate fluxes were seasonally invariant. Annual aerosol dry deposition fluxes (kg ha(-1)) were 0.5 (Na(+)), 0.25 (NH(4)(+)), 0.39 (K(+)), 0.51 (Mg(2+)), 3.19 (Ca(2+)), 1.34 (Cl(-)), 4.47 (NO(3)(-)), 3.59 (SO(4)(2-)), 0.58 (oxalate), 0.71 (HCOO(-)), and 1.38 (CH(3)COO(-)). Contributions of this mechanism to combined aerosol dry deposition and precipitation scavenging (inorganic species, excluding gaseous dry deposition) were 31% (Na(+)), 8% (NH(4)(+)), 26% (K(+)), 63% (Mg(2+)), 66% (Ca(2+)), 32% (Cl(-)), 33% (NO(3)(-)), and 36% (SO(4)(2-)).

A 4.2 kDa synthetic peptide as a potential probe to evaluate the antibacterial activity of coumarin drugs

The coumarin antibiotics are potent inhibitors of DNA replication whose target is the enzyme DNA gyrase, an ATP-dependent bacterial type II topoisomerase. The coumarin drugs inhibit gyrase action by competitive binding to the ATP-binding site of DNA gyrase B protein. The production of new biologically active products has stimulated additional studies on coumarin-gyrase interactions. In this regard, a 4.2 kDa peptide mimic of DNA gyrase B protein from Escherichia coli has been designed and synthesized. The peptide sequence includes the natural fragment 131-146 (coumarin resistance-determining region) and a segment containing the gyrase-DNA interaction region (positions 753-770). The peptide mimic binds to novobiocin (K-a = 1.4 +/- 0.3 x 10(5) m(-1)), plasmid (K-a = 1.6 +/- 0.5 x 10(6) m(-1)) and ATP (K-a = 1.9 f 0.4 x 10(3) m(-1)), results previously found with the intact B protein. on the other hand, the binding to novobiocin was reduced when a mutation of Arg-136 to Leu-136 was introduced, a change previously found in the DNA gyrase B protein from several coumarin-resistant clinical isolates of Escherichia coLi. In contrast, the binding to plasmid and to ATP was not altered. These results suggest that synthetic peptides designed in a similar way to that described here could be used as mimics of DNA gyrase in studies which seek a better understanding of the ATP, as well as coumarin, binding to the gyrase and also the mechanism of action of this class of antibacterial drugs. Copyright (C) 2004 European Peptide Society and John Wiley Sons, Ltd.

Self-assembled FePt nanocrystals with large coercivity: Reduction of the fcc-to-L1(0) ordering temperature

Herein we report the synthesis and properties of Fe55Pt45 nanoparticles, both monodisperse and self-assembled into hexagonal close-packed and cubic arrays of 4.0 +/- 0.2 nm size in an L1(0) structure, obtained by a modified polyol process. The new synthetic route improved the control over the particle composition, thereby reducing the temperature required to convert from face-centered cubic (fcc) to face-centered tetragonal (fct) phase by some 30-50 degrees C without additives. Annealing at 550 degrees C for 30 min converts the self-assembled nanoparticles into ferromagnetic nanocrystals with large coercivity, H-C = 11.1 kOe. Reducing the fcc-to-fct (L1(0)) ordering temperature avoided particle coalescence and decreased the loss in particle positional order without compromising the magnetic properties, as is generally observed when additives are used.

Development of a voltammetric sensor for chromium(VI) determination in wastewater sample

Screen-printed carbon electrode (SPCE) modified with poly-L-histidine film can be successfully applied for chromium(VI) determination based on its pre-concentration. Optimum adherence and stability of the POIY-L-histidine film was obtained by direct addition of PH solution 1% (w/v) on the electrode surface, followed by heating at 80 degrees C during 5 min. Linear response range, sensitivity and limit of detection were 0. 1-150 [mu mol L-1, 4. 13 LA mu mol L` and 0.046 mu mol L-1. The repeatability of the proposed sensor, evaluated in terms of relative standard deviation, was measured as 3.2% for 10 experiments in 40 mu mol L-1 using the same electrode and 4.0% using screen-printed electrode as disposable sensor, respectively. The voltammetric sensor was applied to determination of Cr(VI) and indirect determination of Cr(III) in wastewater samples previously treated by a leather dyeing industry and the average recovery for these samples was around 97%. (C) 2006 Elsevier B.V. All rights reserved.

Determination of 2,4-dichlorophenoxyacetic acid and its major transformation product in soil samples by liquid chromatographic analysis

The 2,4-dichlorophenoxyacetic acid (2,4-D) is one of the most applied herbicides around the world to control broad leave herbs in many crops: In this study, a method was developed for simultaneous extraction and determination of 2,4D and its major transformation product, i.e., the 2,4-dichlorophenol (2,4-DCP), in soil samples. The herbicide and its degradation product were extracted twice from soil samples, after acidification, by dichloromethane on ultrasound system for 1 h. Both extracts were combined and filtrated in qualitative filter paper and Celitee. The total extract was concentrated in rotatory evaporator, dried under N-2 and finally dissolved in 1 ml of methanol. High Performance Liquid Chromatography with UV detection at 230 nm was used for analysis. Recoveries were obtained from soil samples fortified at 0.1, 1.0, 2.0, 3.0 and 4.0 mg kg(-1) levels and the results varied from 85 to 111% (for 2,4-D) and from 95 to 98% (for 2,4-DCP). For both compounds, the limits of quantification were 0.1 mg kg(-1), which were the loss level at which the accuracy and the precision were studied. Nevertheless, the limits of detection, calculated by considering the blank standard deviation and the minimum concentration level, were 0.03 and 0.02 mg kg for 2,4-D and 2,4-DCP, respectively. This proposed method was applied to soil samples of eucalyptus crops, which was previously treated with the herbicide. Despite that, neither 2,4-D nor its degradation product were detected 30 days after the herbicide application. (C) 2003 Elsevier B.V. B.V. All rights reserved.