Effect of bead overlapping on the microstructure and mechanical properties of CoCrWC alloy coatings

In order to protect industrial components, cobalt base alloys are applied as hardfacing material through welding techniques. A large number of papers have shown that controlling the chemical composition is a key point regarding the wear and corrosion resistance of coatings. This paper investigated the effect of bead overlapping on the microstructure and properties of CoCrWC alloy coatings. Mechanical properties were determined by hardness, sliding wear and microtensile tests. Bead overlapping reduces dilution during the previous bead melting, which in turn induces lower iron content. From the second bead on, an increase in the amount of interdendritic carbides and solid solution alloying was verified, accounting for the higher mechanical properties of the coatings

Evaluation of the efficacy of Alpron disinfectant for dental unit water lines

AIMS: To assess the efficacy of a disinfectant, Alpron, for controlling microbial contamination within dental unit water lines. METHODS: The microbiological quality of water emerging from the triple syringe, high speed handpiece, cup filler and surgery hand wash basin from six dental units was assessed for microbiological total viable counts at 22 degrees C and 37 degrees C before and after treatment with Alpron solutions. RESULTS: The study found that the use of Alpron disinfectant solutions could reduce microbial counts in dental unit water lines to similar levels for drinking water. This effect was maintained in all units for up to six weeks following one course of treatment. In four out of six units the low microbial counts were maintained for 13 weeks. CONCLUSIONS: Disinfectants may have a short term role to play in controlling microbial contamination of dental unit water lines to drinking water quality. However, in the longer term attention must be paid to redesigning dental units to discourage the build up of microbial biofilms

OCORRÊNCIA E DIVERSIDADE DA FAUNA EDÁFICA SOB DIFERENTES SISTEMAS DE USO DO SOLO

A fauna edáfica é componente de grande importância da biodiversidade do solo e é alterada pela adubação, calagem e sistemas de cultivos agrícolas. O trabalho objetivou determinar a ocorrência e diversidade da fauna edáfica em áreas submetidas a diferentes sistemas de uso do solo. O levantamento da fauna edáfica ocorreu por meio de armadilhas tipo PROVID, em um arranjo fatorial (7 x 2), sendo sete tipos de usos do solo: área com Braquiária; Campo Nativo; Horta com um ano; Horta com 10 anos de cultivo e aplicação de cama de aviário; resteva de Milho; resteva de Soja e Mata Nativa, duas épocas distintas (maio e outubro), com seis repetições. Os organismos foram classificados pela ordem taxonômica e funcional e foram determinadas e calculadas a abundância de organismos edáficos, índices de Riqueza de Margaleff, de Dominância de Simpson, diversidade de Shannon e equitabilidade de Pielou. A área de Horta com 10 anos de adição de cama de aves, em grandes volumes, apresentou menor diversidade de organismos ocasionada pela ocorrência de elevada população de Colêmbolos. A análise de agrupamento mostrou que sistemas de uso do solo com adição constante de resíduos orgânicos, como a cama de aves, possibilitam maior abundância de organismos edáficos

POTENCIAL DA ASSOCIAÇÃO Pisolithus microcarpus COM MUDAS DE Corymbia citriodora EM SOLO CONTAMINADO COM ZINCO

http://dx.doi.org/10.5902/1980509821109The use of microorganisms potential association with plants is a common practice in soil contaminated by heavy metals, considered low-cost and environmentally friendly. This study aimed to evaluate the growth of Corymbia citriodora (Hook.) K. D. Hill & L.A.S. Johnson and the effect of Pisolithus microcarpus UFSC-Pt116 inoculation in soil contaminated with Zn. The design was completely randomized in a factorial arrangement (2 x 6), with and without inoculum and six doses of Zn (0, 300, 600, 900, 1200 and 1500 mg kg-1 soil), with six replications. Seedlings were inoculated and cultured for 90 days in nursery. After 67 days of transplantation was evaluated the ectomycorrhizal colonization percentage, plant height, stem diameter, number of leaves, chlorophyll index, root volume, leaf dry weight, stem, root and total, dry mass ratio / root dry mass and height / stem diameter. The ectomycorrhizal colonization percentage in Corymbia citriodora is stimulated by adding up to 1412.21 mg kg-1 Zn. The Corymbia citriodora is tolerant to the addition of up to 1500 mg kg-1 of zinc in soil with 81% clay even without inoculation with Pisolithus microcarpus.The canonical correlation analysis shows that inoculation with P. microcarpus favors total dry mass, root and aerial part of Corymbia citriodora grown in soil with 81% clay contaminated with  600 mg kg-1 Zn.http://dx.doi.org/10.5902/1980509821109O uso de plantas com potencial de associação com microrganismos é uma prática frequente em solos contaminados por metais pesados, considerada de baixo custo e ambientalmente correta. O trabalho objetivou avaliar o crescimento do Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson e o efeito da inoculação com Pisolithus microcarpus UFSC-Pt116 em solo contaminado com Zn. O delineamento experimental foi inteiramente casualizado em arranjo fatorial (2 x 6), sendo com e sem inóculo e seis doses de Zn (0, 300, 600, 900, 1200 e 1500 mg kg-1 de solo), com seis repetições. As mudas foram inoculadas e cultivadas durante 90 dias em viveiro. Após 67 dias do transplante definitivo foi avaliado o percentual de colonização ectomicorrízica, a altura de planta, diâmetro do colo, número de folhas, índice de clorofila total, volume radicular, massa seca das folhas, da haste caulinar, radicular e total, relação massa seca aérea/massa seca radicular e a relação altura/diâmetro do colo. O percentual de colonização ectomicorrízica em Corymbia citriodora é estimulado pelo acréscimo de até 1412,21 mg kg-1 de Zn no solo. O Corymbia citriodora é tolerante a adição de até 1500 mg kg-1 de zinco em solo com 81% de argila, mesmo sem a inoculação com Pisolithus microcarpus. A análise de correlação canônica evidencia que a inoculação com P. microcarpus favorece a massa seca total, radicular e da parte aérea de Corymbia citriodora cultivado em solo com 81% de argila contaminada com  600 mg kg-1 de Zn

POTENTIAL ASSOCIATION WITH SEEDLINGS Pisolithus microcarpus Corymbia citriodora IN SOIL CONTAMINATED WITH ZINC

O uso de plantas com potencial de associa\ue7\ue3o com microrganismos \ue9 uma pr\ue1tica frequente em solos contaminados por metais pesados, considerada de baixo custo e ambientalmente correta. O trabalho objetivou avaliar o crescimento do Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson e o efeito da inocula\ue7\ue3o com Pisolithus microcarpus UFSC-Pt116 em solo contaminado com Zn. O delineamento experimental foi inteiramente casualizado em arranjo fatorial (2 x 6), sendo com e sem in\uf3culo e seis doses de Zn (0, 300, 600, 900, 1200 e 1500 mg kg-1 de solo), com seis repeti\ue7\uf5es. As mudas foram inoculadas e cultivadas durante 90 dias em viveiro. Ap\uf3s 67 dias do transplante definitivo foi avaliado o percentual de coloniza\ue7\ue3o ectomicorr\uedzica, a altura de planta, di\ue2metro do colo, n\ufamero de folhas, \uedndice de clorofila total, volume radicular, massa seca das folhas, da haste caulinar, radicular e total, rela\ue7\ue3o massa seca a\ue9rea/massa seca radicular e a rela\ue7\ue3o altura/di\ue2metro do colo. O percentual de coloniza\ue7\ue3o ectomicorr\uedzica em Corymbia citriodora \ue9 estimulado pelo acr\ue9scimo de at\ue9 1412,21 mg kg-1 de Zn no solo. O Corymbia citriodora \ue9 tolerante a adi\ue7\ue3o de at\ue9 1500 mg kg-1 de zinco em solo com 81% de argila, mesmo sem a inocula\ue7\ue3o com Pisolithus microcarpus. A an\ue1lise de correla\ue7\ue3o can\uf4nica evidencia que a inocula\ue7\ue3o com P. microcarpus favorece a massa seca total, radicular e da parte a\ue9rea de Corymbia citriodora cultivado em solo com 81% de argila contaminada com 600 mg kg-1 de Zn.The use of microorganisms potential association with plants is a common practice in soil contaminated by heavy metals, considered low-cost and environmentally friendly. This study aimed to evaluate the growth of Corymbia citriodora (Hook.) K. D. Hill & L.A.S. Johnson and the effect of Pisolithus microcarpus UFSC-Pt116 inoculation in soil contaminated with Zn. The design was completely randomized in a factorial arrangement (2 x 6), with and without inoculum and six doses of Zn (0, 300, 600, 900, 1200 and 1500 mg kg-1 soil), with six replications. Seedlings were inoculated and cultured for 90 days in nursery. After 67 days of transplantation was evaluated the ectomycorrhizal colonization percentage, plant height, stem diameter, number of leaves, chlorophyll index, root volume, leaf dry weight, stem, root and total, dry mass ratio / root dry mass and height / stem diameter. The ectomycorrhizal colonization percentage in Corymbia citriodora is stimulated by adding up to 1412.21 mg kg-1 Zn. The Corymbia citriodora is tolerant to the addition of up to 1500 mg kg-1 of zinc in soil with 81% clay even without inoculation with Pisolithus microcarpus.The canonical correlation analysis shows that inoculation with P. microcarpus favors total dry mass, root and aerial part of Corymbia citriodora grown in soil with 81% clay contaminated with 600 mg kg-1 Zn

EFFECTS OF COPPER ON GROWTH AND QUALITY OF Stryphnodendron polyphyllum Mar. AND Cassia multijuga Rich.

A contamina\ue7\ue3o do solo com cobre tem se tornado comum em regi\uf5es de minera\ue7\ue3o e agr\uedcolas pelo uso de fungicidas a base de cobre e aplica\ue7\ue3o de dejeto l\uedquido de su\uedno ao solo, causando redu\ue7\ue3o na produtividade das plantas. O trabalho objetivou determinar o efeito de doses de cobre no crescimento e qualidade de mudas de Barbatim\ue3o ( Stryphnodendron polyphyllum Mart.) e C\ue1ssia ( Cassia multijuga Rich.). O delineamento experimental foi inteiramente casualizado num fatorial (2 x 4), sendo as duas esp\ue9cies florestais, e quatro doses de cobre: 0; 150; 300 e 450 mg kg-1, com 10 repeti\ue7\uf5es. Avaliou-se a altura de planta, di\ue2metro do colo, peso da mat\ue9ria seca radicular e da parte a\ue9rea, comprimento e \ue1rea superficial espec\uedfica radicular, e os \uedndices de qualidade de mudas: rela\ue7\ue3o entre altura da parte a\ue9rea e di\ue2metro do coleto; altura da parte a\ue9rea e peso da mat\ue9ria seca da parte a\ue9rea e o \ucdndice de Qualidade de Dickson. Os resultados demonstram que as doses de cobre testadas n\ue3o influenciam a qualidade de mudas da C\ue1ssia enquanto o Barbatim\ue3o mant\ue9m a qualidade de mudas at\ue9 300 mg kg-1 de cobre adicionado ao solo. O Barbatim\ue3o apresenta maior crescimento e qualidade de mudas que a C\ue1ssia em solo contaminado com cobre.Soil contamination with copper has become common in the mining and agricultural regions by the use of copper-based-fungicide and application of liquid swine slurry to the soil, causing a reduction in plant productivity. Therefore, a study was undertaken to determine the effect of copper doses in growth and quality of Barbatim\ue3o ( Stryphnodendron polyphyllum Mart.) and Cassia ( Cassia multijuga Rich.) seedlings. The experimental design was completely randomized in a factorial (2 x 4) being the two forest species and four doses of copper: 0, 150, 300 and 450 mg kg-1, with 10 repetitions. It was evaluated plant height, stem diameter, dry weight of shoot and root length and specific root surface area, and the quality indexes of seedlings: relationship between shoot height and diameter of the collar; height and shoot dry weight of shoots and Dickson Quality Index. The results revealed that the copper doses tested does not change the quality of seedlings of Cassia and that Barbatim\ue3o maintains the quality of seedlings up to 300 mg kg-1 of copper added to soil. Barbatim\ue3o presents greater growth and quality than Cassia seedlings in soil contaminated with copper

INTERFERENCE OF DOSES OF COPPER ON GROWTH AND QUALITY OF Bauhinia forficata Link, Pterogyne nitens Tul AND Enterolobium contortisiliquum Vell. SEEDLINGS

O cobre \ue9 um elemento essencial \ue0s plantas, mas quando presente em altas concentra\ue7\uf5es no solo pode se tornar t\uf3xico ao metabolismo vegetal. Uma das estrat\ue9gias para reabilita\ue7\ue3o de \ue1reas contaminadas por metais \ue9 a fitorremedia\ue7\ue3o, que consiste na introdu\ue7\ue3o de esp\ue9cies vegetais no solo contaminado. O trabalho objetivou avaliar a interfer\ueancia de doses crescentes de cobre aplicadas ao solo no crescimento e na qualidade de mudas de Bauhinia forficata Link, Pterogyne nitens Tul e Enterolobium contortisiliquum Vell. O experimento foi conduzido em casa de vegeta\ue7\ue3o, no delineamento inteiramente casualizado, com oito repeti\ue7\uf5es, em arranjo fatorial (3 x 6), sendo tr\ueas esp\ue9cies florestais e seis doses de cobre no solo (0, 60, 120, 180, 240 e 300 mg kg-1). Foram avaliados os par\ue2metros: altura, di\ue2metro de colo, massa seca a\ue9rea, massa seca radicular, \ue1rea superficial espec\uedfica e \uedndice de qualidade de Dickson. Os resultados evidenciaram que as mudas de timba\ufava s\ue3o mais tolerantes do que as de pata-de-vaca e carne-de-vaca e apresentam melhor qualidade de mudas em doses mais elevadas de cobre. As doses de cobre reduzem com maior intensidade a altura de plantas, massa seca da parte a\ue9rea e ra\uedzes, \ue1rea superficial espec\uedfica e o \uedndice de qualidade de Dickson das mudas de Bauhinia forficata Link e Pterogyne nitens Tul em rela\ue7\ue3o \ue0 Enterolobium contortisiliquum Vell. As mudas de timba\ufava toleram maiores doses de cobre no solo em rela\ue7\ue3o \ue0 pata-de-vaca e \ue0 carne-de-vaca.Copper is an essential element for the plants, but when it\u2019s present in high amounts in soil, it becomes toxic to vegetable metabolism. One of the strategies for rehabilitation of contaminated areas by metals is the phytoremediation, which consists in the introduction of vegetable species on contaminated soil. The research aimed to evaluate the interference of increasing doses of copper, applied in soil, on growth and on quality of seedling of Bauhinia forficata Link, Pterogyne nitens Tul e Enterolobium contortisiliquum Vell. The experiment was conducted in a greenhouse, completely randomized design, with eight repetitions and in factorial arrangement (3 x 6), which include three forest species and six copper dosages in soil (0, 60, 120, 180, 240 end 300 mg kg-1). It was evaluated the following parameters: height, collar diameter, aerial dry mass, root dry mass, specific surface area and Dickson Quality Index. The results evidenced that the Enterolobium contortisiliquum Vell seedlings are more tolerant than Bauhinia forficata Link and Pterogyne nitens Tul seedlings and they have better quality of seedlings at higher doses of copper. Copper doses reduce with higher intensity plant height, dry mass of aerial and roots parts, specific surface area and Dickson Quality Index of seedlings of Bauhinia forficata Link and Pterogyne nitens Tul in relation to Enterolobium contortisiliquum Vell Seedlings of Enterolobium contortisiliquum Vell are more tolerant to higher copper doses than Bauhinia forficata Link and Pterogyne nitens Tul in soil

Óleo essencial de eucalipto para indução de micorriza em arbóreas nativas

The slow development of native tropical tree species may be related to their difficulty in establishing ectomycorrhizal associations in natural conditions. We aimed to evaluate the influence of the eucalyptus essential oil on the growth and on the induction of ectomycorrhiza formation in “bracatinga” (Mimosa scabrella Benth.) and “grápia” (Apuleia leiocarpa (Vogel) J.F.Macbr.). The ectomycorrhizal isolate used was Pisolithus microcarpus. Under laboratory conditions, plants were individually subjected to a completely randomized experimental design with four treatments (plant only (control), essential oil, inoculum only, and inoculum + essential oil). We evaluated plant height, shoot and root fresh weight, number of leaves, shoot dry weight, length of the main root, presence of fungal structures, percentage of root colonization, and the effective contribution of treatments for shoot dry weight production. The addition of both the essential oil and P. microcarpus did not induce the formation of typical ectomycorrhizal structures in bracatinga seedlings. The use of the eucalyptus essential oil alone may contribute to the establishment of the association with P. microcarpus in roots of grápia seedlings. The presence of P. microcarpus increased the height of both bracatinga and grápia seedlings grown in vitro, as well as the shoot dry weight of the former.O desenvolvimento lento de arbóreas nativas de clima tropical pode estar relacionado à dificuldade do estabelecimento de ectomicorriza em condições naturais. O objetivo do trabalho foi avaliar a influência do óleo essencial de eucalipto no crescimento e para indução de ectomicorriza em Bracatinga (Mimosa scabrella Benth.) e Grápia (Apuleia leiocarpa (Vogel) J.F.Macbr.). O isolado ectomicorrízico utilizado foi o Pisolithus microcarpus. Em condições de laboratório, individualmente as plantas foram submetidas a um delineamento inteiramente casualizado com quatro tratamentos (somente planta (controle), óleo essencial, somente inóculo e inóculo + óleo essencial). Avaliou-se a altura de planta, massa fresca da parte aérea e do sistema radicular, número de folhas, massa seca da parte aérea, comprimento da raiz principal, presença de estruturas fúngicas, percentual de colonização radicular e a contribuição efetiva dos tratamentos para produção de massa seca da parte aérea. A adição de óleo essencial e do isolado P. microcarpus não possibilita a formação de estruturas típicas de ectomicorriza nas plântulas de Bracatinga. A utilização de óleo essencial de eucalipto pode contribuir para o estabelecimento de associação de P. microcarpus nas raízes das plântulas de Grápia. A presença de P. microcarpus aumenta altura das plântulas de Bracatinga e Grápia e a massa seca da parte aérea da Bracatinga produzidas in vitro

Isolation of a Human Anti-HIV gp41 Membrane Proximal Region Neutralizing Antibody by Antigen-Specific Single B Cell Sorting

Broadly neutralizing antibodies are not commonly produced in HIV-1 infected individuals nor by experimental HIV-1 vaccines. When these antibodies do occur, it is important to be able to isolate and characterize them to provide clues for vaccine design. CAP206 is a South African subtype C HIV-1-infected individual previously shown to have broadly neutralizing plasma antibodies targeting the envelope gp41 distal membrane proximal external region (MPER). We have now used a fluoresceinated peptide tetramer antigen with specific cell sorting to isolate a human neutralizing monoclonal antibody (mAb) against the HIV-1 envelope gp41 MPER. The isolated recombinant mAb, CAP206-CH12, utilized a portion of the distal MPER (HXB2 amino acid residues, 673–680) and neutralized a subset of HIV-1 pseudoviruses sensitive to CAP206 plasma antibodies. Interestingly, this mAb was polyreactive and used the same germ-line variable heavy (VH1-69) and variable kappa light chain (VK3-20) gene families as the prototype broadly neutralizing anti-MPER mAb, 4E10 (residues 672–680). These data indicate that there are multiple immunogenic targets in the C-terminus of the MPER of HIV-1 gp41 envelope and suggests that gp41 neutralizing epitopes may interact with a restricted set of naive B cells during HIV-1 infection

Functional Memory B Cells and Long-Lived Plasma Cells Are Generated after a Single Plasmodium chabaudi Infection in Mice

Antibodies have long been shown to play a critical role in naturally acquired immunity to malaria, but it has been suggested that Plasmodium-specific antibodies in humans may not be long lived. The cellular mechanisms underlying B cell and antibody responses are difficult to study in human infections; therefore, we have investigated the kinetics, duration and characteristics of the Plasmodium-specific memory B cell response in an infection of P. chabaudi in mice. Memory B cells and plasma cells specific for the C-terminal region of Merozoite Surface Protein 1 were detectable for more than eight months following primary infection. Furthermore, a classical memory response comprised predominantly of the T-cell dependent isotypes IgG2c, IgG2b and IgG1 was elicited upon rechallenge with the homologous parasite, confirming the generation of functional memory B cells. Using cyclophosphamide treatment to discriminate between long-lived and short-lived plasma cells, we demonstrated long-lived cells secreting Plasmodium-specific IgG in both bone marrow and in spleens of infected mice. The presence of these long-lived cells was independent of the presence of chronic infection, as removal of parasites with anti-malarial drugs had no impact on their numbers. Thus, in this model of malaria, both functional Plasmodium-specific memory B cells and long-lived plasma cells can be generated, suggesting that defects in generating these cell populations may not be the reason for generating short-lived antibody responses