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Novas tendências buscam cada vez mais agregar valor ao queijo, alterando ingredientes e processos para melhorar atributos sensoriais e incorporando culturas com ação probiótica, como as bactérias láticas conferindo propriedades funcionais. Na perspectiva funcional, o probiótico Lactobacillus casei oferece amplo aspecto tecnológico conferindo benefícios ao produto lácteo e ao consumidor. Sendo o queijo um produto bastante perecível, um dos processos empregados no melhoramento de sua conservação e características organolépticas, é a defumação. Para avaliar como essas propriedades afetam o produto com o decorrer do tempo, foi utilizada a aplicação da microbiologia preditiva. Portanto, este trabalho objetivou produzir, caracterizar e avaliar o crescimento de Bactérias Láticas (BL) através de modelos matemáticos ajustados durante o tempo de prateleira de um queijo meia cura desenvolvido com adição de probiótico (Lactobacillus casei CSL3) sendo defumado ou não com fumaça líquida. Os queijos produzidos classificam-se como gordos (GES: 51%), de média umidade (44,7%) e foram armazenados a 10°C ± 2°C, durante 34 dias. Utilizou-se da microbiologia preditiva, por meio da plataforma online DmFit, para avaliar modelos primários que representassem o comportamento das Bactérias Láticas ao longo do acondicionamento dos produtos, de modo a acompanhar o crescimento do probiótico. Dessa forma, foi possível produzir queijos meia cura defumados ou não que se adequam à legislação e podem ser potenciais probióticos. Além disso, evidenciou-se a possibilidade de utilização da defumação por imersão em fumaça líquida como um processamento de queijo minas meia cura que, apesar de afetar o crescimento das Bactérias Láticas, é capaz de manter a viabilidade da veiculação da cultura probiótica de L. casei no produto final.

Background Pemphigus herpetiformis (PH) is a rare clinical subtype of pemphigus with the presence of urticarial plaques, severe pruritus, rare acantholysis and eosinophilic spongiosis. Objectives The aim of this study was to investigate the influence of IL-31 and pro-inflammatory cytokines/chemokines in the pathogenesis of PH. Methods Twenty-five patients with PH and three groups: pemphigus foliaceus (PF = 14), pemphigus vulgaris (PV = 15) and healthy controls (HC = 20) were selected for this study. The groups were analysed by immunohistochemistry utilizing IL-31, IL-31RA, IL-4, IL-17 and TNF-α antibodies. Serum levels of IL-4, IL-13, TNF, CXCL8, CCL5 and CCL2 were evaluated by cytometric bead array. Results Analysis of IL-31 family of PH patients revealed the following findings: (i) Enhanced in situ expression of IL-31 in PH samples, compared to PF and to PV (epidermis); (ii) Cutaneous IL-31RA expression in PH samples was higher than in PF, PV and HC groups (epidermis and dermis); (iii) PF patients that evolved to PH showed significant increased IL-31RA epidermal expression during the PH phase. Profile of pro-inflammatory cytokines (IL-4, IL-17 and TNF-α) in PH patients' skin exhibited: (i) Enhanced IL-4 expression, when compared to patients with PF (epidermis and dermis) and with PV (epidermis); (ii) Augmented IL-17 expression than PF and PV patients (epidermis); (iii) Augmented expression of TNF-α when compared to PF at the epidermal level. Evaluation of circulating cytokines and chemokines showed higher levels of CXCL8 and CCL2 in PH sera compared to HC group. Conclusions IL-31 and IL-31RA, cytokines related to pruritus, and pro-inflammatory chemokines (CXCL8 and CCL2) seem to exert a role in the pathogenesis of PH. These findings support future studies to clarify the role of IL-31 pathway as a potential therapeutic target for patients with PH.

O Problema do Empacotamento Colorido (CBPP) é uma generalização do Problema do Empacotamento (BPP) onde, dado um conjunto de itens com um tamanho e uma cor, devemos empacotar os itens em recipientes de capacidade limitada, minimizando a quantidade de recipientes utilizados e satisfazendo a restrição que dois itens de mesma cor não podem ser empacotados lado a lado em um mesmo recipiente. Neste artigo, propomos a adaptação de heurísticas do BPP para o CBPP acompanhado de algumas heurísticas novas para o problema. Propomos também uma heurística para o CBPP baseada em Variable Neighborhood Search. Os resultados indicam que a nossa abordagem é capaz de encontrar boas soluções para instâncias grandes do problema.

The objective of this work was to evaluate the influence of shade level on the production of T. myrmecophila seedlings. After 30 days of seedling transplantation, the seedlings were submitted to the following treatments: 100% light (full sun), 75% light and 50% light. The statistical design was completely randomized with 5 replicates of 10 seedlings each per treatment. The data were analyzed by repeated measures in time, in 5 measurements, performed every 30 days (150 days of evaluation). The analyzed variables were shoot height and diameter. The environment with 75% luminosity was the one that contributed most to the growth in height of the seedlings, having presented higher mean values over time, in the 5th month (34.94 cm). The most pronounced effect for growth in diameter was verified in the 5th month of evaluation, where the highest average was obtained in the environment with 50% of shading (4.61 mm). The T. myrmecophila seedlings were influenced by the shading levels used. From the results evaluated, treatments with 75% and 50% of solar radiation provided superior growth for dendrometric variables height and diameter, respectively. Therefore, we recommend environments with 75% and 50% of solar radiation for the production of T. Myrmecophila seedlings.

Several review studies exist in the literature about monitoring, fault detection, and diagnosis of power transformers. However, they are general approaches in terms of power transformers. Some only focus on applying a specific class of techniques, but again, for general power transformers. Other reviews focus on applying different technologies such as fiber optics, thermal cameras, and vibration sensors, but all within the perspective of general power transformers. A significant question remains: among all types of power transformers, which specific techniques should be used, and why are they more adequate? What are the uncertainties that can decrease their precision? What about the balance, in terms of costs, associated with applying a certain technique and the return needed for a particular type of transformer? In this context, this paper is not only a literature review of well-known problems related to power transformers. Here, we do not just center on large power transformers (100 MVA or higher). Still, we describe a case study of a phase-shifting 1400 MVA-400 kV three-phase transformer that currently connects two European countries that began to show signs of abnormal operating conditions in 2012. In this way, the need to detect and identify anomalies in their initial stage of development for a possible preventive maintenance action is more than justified, which is essentially achieved with continuous monitoring models of the transformer, as concluded in this paper.

Since electrons in a ballistic regime perceive a carbon nanotube or a graphene layer structure as a continuous medium, we can use the study of the quantum dynamics of one electron constrained to a curve or surface to obtain a qualitative description of the conduction electrons' behavior. The confinement process of a quantum particle to a curve or surface leads us, in the so-called "confining potential formalism" (CPF), to a geometry-induced potential (GIP) in the effective Schr\"odinger equation. With these considerations, this work aims to study in detail the consequences of constraining a quantum particle to a helix, catenary, helicoid, or catenoid, exploring the relations between these curves and surfaces using differential geometry. Initially, we use the variational method to estimate the energy of the particle in its ground state, and thus, we obtain better approximations with the use of the confluent Heun function through numerical calculations. Thus, we conclude that a quantum particle constrained to an infinite helix has its angular momentum quantized due to the geometry of the curve, while in the cases of the catenary, helicoid, and catenoid the particle can be found either in a single bound state or in excited states which constitute a continuous energy band. Additionally, we propose measurements of physical observables capable of discriminating the topologies of the studied surfaces, in the context of topological metrology.

Metal complexes based on ruthenium have established excellent activity with less toxicity and great selectivity for tumor cells. This study aims to assess the anticancer potential of ruthenium(II)/allopurinol complexes called [RuCl

This study aimed to evaluate the effects of diet supplementation with monensin and saponins alone or combined with essential oils (EOs) on the nutrient intake and apparent digestibility, rumen fermentation parameters, microbial population, nitrogen balance, ruminal microbial protein synthesis, blood metabolites, and milk composition, yield and fatty acid profile of mid- to late-lactating Jersey cows. Eight ruminally cannulated lactating Jersey cows (average 17.6 ± 5.5 kg/day of milk yield and 100.5 ± 26.6 days of milk (mean ± SD)) were distributed in a replicated 4 × 4 Latin square design with 21-day periods (last seven days for sampling). Treatment sequences were randomly designated to cows and consisted of: (1) CON - Control, no feed additive; (2) SAP - 16 g/cow/day of a supplement based on whole-seed fenugreek powder (variety Fenucold) standardized to diosgenin, one of the major steroidal sapogenins of fenugreek (2000 mg/kg); (3) SAPEO - SAP supplement combined with a blend of natural EOs with major components of carvacrol (2500 mg/kg), cinnamaldehyde (5600 mg/kg) and limonene (3000 mg/kg); and (4) MON - Monensin, inclusion of monensin sodium in the diet at 24 mg/kg DM. Cows fed CON showed higher dry matter, organic matter, crude protein and ether extract intakes than animals fed MON, whereas higher neutral detergent fibre intake was observed in animals fed SAPEO than those fed MON (P

Microbial lipases are prominent biocatalysts able to catalyze a wide variety of reactions in aqueous and nonaqueous media. In this work, filamentous fungi isolated from leaves decomposed in an aquatic environment were screened for lipase production with hydrolytic activity and esterification. Agar plates with Tween 20 and Rhodamine B were used for selection, while submerged cultures with olive oil were subsequently used to select 38 filamentous fungi. Trichoderma harzianum, Fusarium solani, Trichoderma harzianum F5, and Penicillium sp. F36 were grown in six different culture media. F. solani presented the highest lipase production (2.37 U/mL) with esterification activity of 0.07 U/mL using medium composed of (g.L−1) KH2PO4 1.00, MgSO4 H2O 1.123, and CuSO4 0.06. Supplementation of this culture medium with organic nitrogen sources increased lipase production by 461.3% using tryptone and by 419.4% using yeast extract. Among the vegetable oils from the Amazon region, degummed cotton oil induced lipase production up to 8.14 U/mL. The lipase produced by F. solani F61 has great potential to application in conventional processes and biodiesel production by transesterification of vegetable oils, as well as food industries in the production of fatty acid esters by hydrolysis and esterification.

The objective was to evaluate the correlation between behaviour al and intake variables of Holstein calves fed pellets and meal. Twelve pure Holstein calves with initial average age of 10 days and weight of 27.5 kg were used; The experimental design used in this study was a 2 x 2 factorial Original Research Article Silva et al.; AJEA, 7(6): 382-388, 2015; Article no.AJEA.2015.138 383 design (two types of feed and two feeding stages lactation and post-lactation periods), with six repetitions. Was found significant effects the time allocated to eating, rumination and resting. The data concerning the efficiency of feeding and rumination, total chewing time, number of ruminal boluses, rumination time/bolus and the number of chews per cud/bolus and discretization of the time series. There was a moderate positive correlation between the variable behaviour: dry matter per bolus, number of discrete eating and resting periods and the variable of dry matter intake (DMI). There was a strong positive correlation between the variables of behaviour: total chewing time, NDF/BOLUS, ADF/ BOLUS and neutral detergent fiber (NDF) and acid detergent fiber (ADF) intake variables. There was a negative moderate correlation between the behaviour variable TRP (time resting period) and the NDF and ADF intake variables. According to the correlations found in this study, between the behaviour aspects and intake of NDF and ADF can support studies aimed to the formulation of diets supplemented based the understanding on behaviour of food intake by animals.

Coaxial electrospinning process was used to produce biodegradable membranes made of coreshell fibers of a poly(lactic acid) (PLA) shell and a poly(vinyl alcohol) (PVA) core. Scanning electron microscopy analyses of these structures showed that the PLA shell can present certain porosity depending on the process condition. FTIR-ATR and contact angle measurements also suggested imprisonment of the PVA core within the PLA shell. This type of structure was also confirmed by means of transmissions electron microscopy. The morphology of these fibers was dependent on the flow rate of both core and shell solutions, and homogeneous and smooth surface was only attained when the flow rate of the external PLA solution was 4 times the flow rate of the internal PVA solution. The increase in the PLA solution flow rate increases the diameter of the core-shell fiber which reaches up to 1.7 μm. Nevertheless, fibers with smaller average diameter could also be produced (200 nm). These core-shell fibers presented improved hydrophilicity as compared with monolithic PLA fibers.

The objective was to evaluate the ingestive behavior of crossbred heifers finished on a Brachiaria brizantha cv. Marandu pasture receiving four levels of glycerin in their supplementation. Thirty-six crossbred heifers with average initial weight of 264.83±3.83 kg and 20 months of age were distributed into a completely randomized design with four treatments and nine replications: control (0%), 4.82%, 10.12%, and 15.56% glycerin in the dry matter. The grazing time reduced linearly (p 0.05). The number of rumination periods reduced linearly (p 0.05) whereas the feed efficiency of neutral detergent fiber reduced linearly (p

As three-core wire-armoured submarine cables become progressively more relevant, the need for refined modelling techniques grows likewise. IEC Standard 60287 indications though are still widely recognized to be insufficiently accurate, since several effects due to the presence of the collective wire armour are ignored. This paper therefore offers an insight into the induced losses mechanism as a function of the armour wires electromagnetic properties. The analysis is focused on the influence of the armour transverse permeability, whose overall resultant value is estimated by means of a simplified yet effective formulation. Such analytical approach is tested in a 2D FEM environment in terms of power losses distribution and compared both to the IEC indications and to an existing formula in the literature. It is found that the values of permeability proposed by the IEC Standard underestimate the induced sheath power losses due to the presence of the armour, whereas the proposed approach improves the accuracy, as the magnetic flux density enhancement within the cable is accounted for.

A novel uni-body composite pylon has been proposed for 400 kV transmission lines with advantages of compacted size, friendly looking and cost competitiveness. As its configuration is quite different from the traditional lattice pylon, its electrical performance needs in-depth investigation and evaluation, for which electrical testing methods are essential. However, as research on composite-based pylons is still in initial stage, leaving international standards and theoretical analysis on this topic very limited, effective testing methods to evaluate the fully composite pylon’s electrical performance need to be studied. This paper sums up experience and key advances on testing methods to evaluate electrical performance of composite cross-arms and composite-based pylons. Based on state of the art review, several feasible testing methods that can be used to verify the feasibility of the novel uni-body composite pylon are put forward.

The simulation of an electromagnetic transient is only as good as the model's data and the level of detail put into the modeling. One parameter with influence in the results is the size of the modeling of the area around the switched-on line. If the area is too small, the results are inaccurate. If the area is too large, the simulation requires a long period of time and numerical problems are more likely to exist. This paper proposes a method that can be used to estimate the depth of the modeling area using the grid layout, which can be obtained directly from a PSS/E file, or equivalent. The simulation of electromagnetic transients in cable-based networks requires larger computational effort than in an equivalent overhead-line (OHL)-based network. Therefore, the method is demonstrated for the former, with the cases of OHL-based networks and hybrid cable-OHL networks addressed in a future paper. One of the main reasons behind the long simulation times of a cable-based network is the simulation of all the cross-bonded sections. The introduced method can also be used to minimize the modeling of the cross-bonded sections.

Oral Diseases (2011) 17, 258–264 Objective: To analyse and compare the expression of Palate, Lung, and Nasal Epithelium Clone (PLUNC) proteins in salivary glands from patients with and without AIDS (control group) using autopsy material. Methods: We analysed the expression of PLUNCs using immunohistochemistry in parotid (n = 45), submandibular (n = 47) and sublingual gland (n = 37) samples of AIDS patients [30 with normal histology, 21 with mycobacteriosis, 14 with cytomegalovirus (CMV) infection, 30 with chronic non-specific sialadenitis, and 30 HIV-negative controls. In situ hybridization (ISH) for SPLUNC 2 in the HIV-negative group was performed. Results: SPLUNC 1 expression was detected in the mucous acini of submandibular and sublingual glands, and SPLUNC 2 were seen in the serous cells. LPLUNC 1 expression was only positive in the salivary ducts. There was a higher expression of SPLUNC 2 in AIDS patients with CMV infection and mycobacteriosis when compared with all other groups. The intensity of staining for SPLUNC 2 was greater around the lesions than the peripheral ones. ISH for SPLUNC 2 showed perinuclear positivity in the serous cells in all HIV-negative cases. Conclusions: SPLUNC 1 and LPLUNC 1 proteins were similarly expressed in the salivary glands of AIDS patients and non-HIV patients. CMV infection and mycobacteriosis increase SPLUNC 2 expression in serous cells in the salivary gland of AIDS patients.

It is essential to study the correlations between traits of genetic breeding, principally, when selection for a trait is impaired by low heritability or difficulties with measurement and identification. This study aimed to estimate genotypic correlations among 15 morpho-agronomic traits in papaya. Results indicated that early selection for greater stem diameter (SD) can result in more productive plants. Although correlations between normal flowers and commercial fruits, estimated in the same period of evaluation, cannot be recommended for the selection procedures, the correlations between deformed flowers and carpelloid and pentandric fruits are reliable enough to be used in the selection procedures if measured in the same period. Deformed flowers and sexual reversion affect the commercial fruit yield, indicating the need for the development of segregating generations for selection in the main producing regions of Brazil.

The objective was to evaluate the ingestive behavior of crossbred heifers finished on a Brachiaria brizantha cv. Marandu pasture receiving four levels of glycerin in their supplementation. Thirty-six crossbred heifers with average initial weight of 264.83±3.83 kg and 20 months of age were distributed into a completely randomized design with four treatments and nine replications: control (0%), 4.82%, 10.12%, and 15.56% glycerin in the dry matter. The grazing time reduced linearly (p0.05). The number of rumination periods reduced linearly (p0.05) whereas the feed efficiency of neutral detergent fiber reduced linearly (p

The aim of this study was to evaluate the influence of ultrasound application on the bond strength of self-adhesives resin cements to dentin. Twenty-four third molars were randomly divided into 4 groups (n = 6/group): G1 - RelyX Unicem; G2 - Maxcem Elite; G3 - RelyX Unicem and ultrasound application; G4 - Marcem Elite and ultrasound application. Composite resin blocks were luted to flat dentin with a load of 500 g for 2 min, followed by light polymerization in G1 and G2. In G3 and G4, the ultrasound device was applied for 20 s on the composite resin block, followed by 500 g load for 1 min and 40 s, and light polymerization. After storage in distilled water at 37 degrees C for 24 h, six tooth/resin sets were cut parallel to the long axis of the tooth, in the x and y directions, with a cross section area of -0.80 mm2. Twenty-four specimens were obtained for each group and submitted to microtensile bond strength (microTBS) testing in a universal testing machine at 0.5 mm/min crosshead speed. According to two-way ANOVA, resin cement (p = 0.000) and cementation method (p = 0.002) were significant. Interaction was not significant (p = 0.676). According to Student's-t test (alpha = 0.05), the microTBS mean with ultrasound application (13.74 MPa) was statistically higher than without it (10.57 MPa). The microTBS mean of RelyX Unicem (13.95 MPa) was statistically higher than Maxcem Elite (10.36 MPa). The ultrasound application increased the microTBS of the RelyX Unicem and Maxcem Elite to dentin.

Digital TM Landsat images integrated with elevation model variables were used to evaluate the potentiality of geobotany for lithological unit discrimination in the tropical rain forest environment of the Carajas Mineral Province, Brazilian Amazon region. The data set was analysed through digital image processing techniques (enhancements and non-supervised classification). The investigation has shown that the Up-Land rain forest vegetation in the area is mainly controlled by elevation and slope which reflect variations in the geology. Botanical verification has also indicated that the physiognomy (density and stratification), would be the most important vegetation attribute which influences the remote sensing responses. The research has provided useful information for the geological model of the area. Thus, by understanding the relationships among vegetation, terrain descriptors and geology, geobotanical remote sensing provides an additional tool for geological exploration in this kind of environment.

To analyse and compare the expression of Palate, Lung, and Nasal Epithelium Clone (PLUNC) proteins in salivary glands from patients with and without AIDS (control group) using autopsy material.We analysed the expression of PLUNCs using immunohistochemistry in parotid (n = 45), submandibular (n = 47) and sublingual gland (n = 37) samples of AIDS patients [30 with normal histology, 21 with mycobacteriosis, 14 with cytomegalovirus (CMV) infection, 30 with chronic non-specific sialadenitis, and 30 HIV-negative controls. In situ hybridization (ISH) for SPLUNC 2 in the HIV-negative group was performed. SPLUNC 1 expression was detected in the mucous acini of submandibular and sublingual glands, and SPLUNC 2 were seen in the serous cells. LPLUNC 1 expression was only positive in the salivary ducts. There was a higher expression of SPLUNC 2 in AIDS patients with CMV infection and mycobacteriosis when compared with all other groups. The intensity of staining for SPLUNC 2 was greater around the lesions than the peripheral ones. ISH for SPLUNC 2 showed perinuclear positivity in the serous cells in all HIV-negative cases. SPLUNC 1 and LPLUNC 1 proteins were similarly expressed in the salivary glands of AIDS patients and non-HIV patients. CMV infection and mycobacteriosis increase SPLUNC 2 expression in serous cells in the salivary gland of AIDS patients.

Background: The natural history and consequences of severe H1N1 influenza infection among cancer patients are not yet fully characterized. We describe eight cases of H1N1 infection in cancer patients admitted to the intensive care unit of a referral cancer center. Patients and methods: Clinical data from all patients admitted with acute respiratory failure due to novel viral H1N1 infection were reviewed. Lung tissue was submitted for viral and bacteriological analyses by real-time RT-PCR, and autopsy was conducted on all patients who died. Results: Eight patients were admitted, with ages ranging from 55 to 65 years old. There were five patients with solid organ tumors (62.5%) and three with hematological malignancies (37.5%). Five patients required mechanical ventilation and all died. Four patients had bacterial bronchopneumonia. All deaths occurred due to multiple organ failure. A milder form of lung disease was present in the three cases who survived. Lung tissue analysis was performed in all patients and showed diffuse alveolar damage in most patients. Other lung findings were necrotizing bronchiolitis or extensive hemorrhage. Conclusions: H1N1 viral infection in patients with cancer can cause severe illness, resulting in acute respiratory distress syndrome and death. More data are needed to identify predictors of unfavorable evolution in these patients.

For effective management of irrigation and fertilization in container media, a complete understanding of their hydraulic properties is essential. This study was conducted to test the applicability of an existing predictive hydraulic model to the calculation of a reliable unsaturated hydraulic conduc

Summary Background To date, little information has been available about pulmonary artery pathology in asthma. The pulmonary artery supplies the distal parts of the lungs and likely represents a site of immunological reaction in allergic inflammation. The objective of this study was to describe the inflammatory cell phenotype of pulmonary artery adventitial inflammation in lung tissue from patients who died of asthma. Methods We quantified the different inflammatory cell types in the periarterial region of small pulmonary arteries in lung tissue from 22 patients who died of asthma [fatal asthma (FA)] and 10 control subjects. Using immunohistochemistry and image analysis, we quantified the cell density for T lymphocytes (CD3, CD4, CD8), B lymphocytes (CD20), eosinophils, mast cells (chymase and tryptase), and neutrophils in the adventitial layer of pulmonary arteries with a diameter smaller than 500 μm. Results Our data (median/interquartile range) demonstrated increased cell density of mast cells [FA=271.8 (148.7) cells/mm2; controls=177.0 (130.3) cells/mm2, P=0.026], eosinophils [FA=23.1 (58.6) cells/mm2; controls=0.0 (2.3) cells/mm2, P=0.012], and neutrophils [FA=50.4 (85.5) cells/mm2; controls=2.9 (30.5) cells/mm2, P=0.009] in the periarterial space in FA. No significant differences were found for B and T lymphocytes or CD4+ or CD8+ subsets. Chymase/tryptase positive (MCCT) mast cells predominated over tryptase (MCT) mast cells in the perivascular arterial space in both asthma patients and controls [MCCT/(MCCT+MCT)=0.91 (0–1) in FA and 0.75 (0–1) in controls, P=0.86]. Conclusions Our results show that the adventitial layer of the pulmonary artery participates in the inflammatory process in FA, demonstrating increased infiltration of mast cells, eosinophils, and neutrophils, but not of T and B lymphocytes.

OCO rays are lines associated with trajectories described by image points in a simulated common-offset section when several velocity fields are used for offset continuation (OCO) transformation. We present a methodology which makes use of OCO rays to find RMS velocity field using only two common-offset sections, which are referred as take-off and target sections, respectively. The main idea of this approach consists of looking for the best correlation between a selected reflection event in the take-off section and the corresponding one in the target section, being the search carried out along the appropriated OCO rays. We successfully apply the methodology in a deep water field dataset obtaining a geologically consistent time interval velocity model.

The role of the sputtering parameters on the properties of thin A12O3 and A1N insulator layers for spin dependent tunneling junctions was studied. A12O3 insulators were prepared by rf sputtering from an A12O3 target in an Ar or Ar-O2 atmosphere and also by plasma oxidation in an O2 atmosphere of a thin Al layer. The thin Al layer was deposited by rf sputtering at room temperature. A1N was prepared by reactive sputtering from an Al target in a Ar-N2 atmosphere. The index of refraction n measured by ellipsometry, was used to optimize the sputtering parameters, and chemical etch rates were used for information on pin-hole density. The aimed values were n=1.75 for A12O3 (corundum structure) and n=2.2 for A1N. For reactively sputtered A12O3, under optimized deposition conditions, n reaches 1.65 for films 300 Å thick. A12O3 thin layers fabricated by plasma oxidation of a thin Al film were also prepared but the oxide layer was too thin for ellipsometry characterization. A1N insulating films show a constant n value of 1.92 from 400 Å down to 60 Å thick films. Rutherford backscattering analysis show that the ratio of Ar to N2 must be less than 1 to avoid O2 incorporation in the film. Junctions of the type glass/buffer/FM/insulator/FM, where FM is either Co or NiFe, were made by contact metal masks with a junction area of 0.25 mm.2 The A12O3 deposited by sputtering from an A12O3 target under conditions expected to give n>1.5 had a magnetoresistance at room temperature MR(RT) of 2.5% with a junction resistance Rj of 2.2 m Ω and by fitting the I-V curve to existing tunneling theory gave an effective barrier thicknesst of 20 Å and a barrier heightΦ of 2.2 eV. These occurred in only one sample (9 junctions) and were not reproducible. The A12O3 insulators prepared by plasma oxidation of a thin Al layer gave a MR(RT)= 4%, tj = 22 Å, Rj=250 k,Ω and Φ =1.4 eV. The A1N insulator with n =1.9 gave a MR(RT)= 1.6 %, t = 20 A, Rj = 4.8 kΦ and barrier height 1.2 eV. In the last two cases junctions with MR at room temperature can be produced with reasonable reproducibility, Al2O3 samples showed a 15–20% increase in MR as the temperature was lowered to 17 K, while AIN junctions show an increase of a factor of 2 in MR at 77 K.

Female Lutzomyia longipalpis were exposed to infection by three different species/strains of Leishmania. When the insects were dissected four days after exposure, stained preparations were made of the flagellates contained in the digestive tract. Using traditional morphometric methods, L. amazonensis, L. guyanensis and an unnamed species of the mexicana complex could be distinguished from one another.

Em áreas da Serra de Carajás, Pará, e em áreas da Cadeia do Espinhaço, Minas Gerais, Brasil, foram coletadas plantas e nelas analisadas as concentrações de Cu, Pb, Ni, Cd, Cr, Co, Mn e Fe. Os resultados indicam que as plantas das áreas de Carajás concentram Cu, Pb, Ni, Cr e Fe acima da normalidade e que as plantas das áreas da Cadeia do Espinhaço concentram Ni, Mn, Cu, Pb, Cd e também Fe. Com base nestes resultados e nos aspectos fisionômicos da vegetação, podemos supor a existência de diferentes tipos de vegetação metalófila nestas áreas, as quais podem pertencer a uma única provir ia biogeoquímica (Carajás - Espinhaço), rica em ferro e outros metais pesados.Plants from Serra dos Carajás, state of Pará, and Cadeia do Espinhaço, state of Minas Gerais, Brazil, were analyzed for Cu, Pb, Ni, Cd, Co, Mn and Fe concentrations. The results indicate that plants from Carajás concentrate Cu, Pb, Ni, Cr and Fe above background values, and those from the state of Minas Gerais concentrate Ni, Mn, Cu, Pb, Cd and also Fe. Based on the results and on the physionomical aspects of the vegetation we can speculate on the existence of différente types of metalophylic vegetation in these areas, which may belong to a single biogeochemical province (Carajás - Espinhaço) which is rich in iron and other heavy metals.