Survey of ACCase and ALS resistance in winter annual grasses identifies target-site and nontarget-site imazamox resistance in Secale cereale.

BACKGROUND: Early detection of herbicide resistance in weeds is crucial for successful implementation of integrated weed management. We conducted a herbicide resistance survey of the winter annual grasses feral rye (Secale cereale), downy brome (Bromus tectorum), and jointed goatgrass (Aegilops cylindrica) from Colorado winter wheat production areas for resistance to imazamox and quizalofop. RESULTS: All samples were susceptible to quizalofop. All downy brome and jointed goatgrass samples were susceptible to imazamox. Out of 314 field collected samples, we identified three feral rye populations (named A, B, and C) that were imazamox resistant. Populations B and C had a target-site mechanism with mutations in the Ser653 residue of the acetolactate synthase (ALS) gene to Asn in B and to Thr in C. Both populations B and C had greatly reduced ALS in vitro enzyme inhibition by imazamox. ALS feral rye protein modeling showed that steric interactions induced by the amino acid substitutions at Ser653 impaired imazamox binding. Individuals from population A had no mutations in the ALS gene. The ALS enzyme from population A was equally sensitive to imazamox as to known susceptible feral rye populations. Imazamox was degraded two times faster in population A compared with a susceptible control. An oxidized imazamox metabolite formed faster in population A and this detoxification reaction was inhibited by malathion. CONCLUSION: Population A has a nontarget-site mechanism of enhanced imazamox metabolism that may be conferred by cytochrome P450 enzymes. This is the first report of both target-site and metabolism-based imazamox resistance in feral rye. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Development of a spectrofluorimetry-based device for determining the acetylene content in the oils of power transformers.

Power transformers are essential for a functioning electrical system and therefore require special attention by maintenance programs because a fault can harm both the company and society. The temperature inside a power transformer and the dissolved gases, which are primarily composed of acetylene, are the two main parameters monitored when detecting faults. This paper describes the development of a device for analyzing the acetylene content in insulating oil using spectrofluorimetry. Using this device introduces a new methodology for the maintaining and operating power transformers. The prototype is currently operating in a substation. The results presented by this system were satisfactory; when compared to chromatographic data, the errors did not exceed 15%. This prototype may be used to confirm the quality of an insulating oil sample to detect faults in power transformers.

Efeito de superfícies de implantes nano-estruturadas na expressão de genes de osteoblastos e no contato osso-implante in vivo / Effect of nanostructured implant surfaces on osteoblast related gene expression and bone-implant contact in vivo

As tendências atuais na terapia com implantes odontológicostêm incluído o uso de implantes com superfícies modificadasutilizando nanotecnologia. Ciência que permite a construçãode novos materiais e dispositivos pela manipulação de átomosindividuais e moléculas (escala menor do que 100nm). O objetivodeste trabalho foi avaliar o papel das modificações em escalananométrica de superfícies de implantes osseointegradospara melhorar o processo de osseointegração. Nanotecnologiaoferece a engenheiros e profissionais da área de biologia e saúdenovos meios para entender e otimizar funções e respostasespecíficas de células. As várias técnicas utilizadas para adicionarcaracterísticas nanométricas às superfícies de implantesosseointegrados são descritas neste trabalho. Vários trabalhostem apresentado os efeitos da nanotecnologia na modulaçãode etapas fundamentais do processo de osseointegração. Asvantagens e desvantagens da utilização da nanotecnologia nasuperfície de implantes também são discutidas nesse trabalho.Posteriormente, em uma série de experimentos in vitro e in vivo,foi possível avaliar o efeito específico destas modificações emdois diferentes modelos. Como efeitos observados da aplicaçãode nanoestruturas à superfície dos implantes osseointegradosfoi possível verificar-se uma melhor e mais rápida resposta deosseointegração destes materiais, atuando efetivamente na cascatade diferenciação de osteoblastos.

Current trends in clinical dental implant therapy include useof endosseous dental implant surfaces embellished with nanoscaletopographies. Nanotechnology deals with materials withat least one significant dimension less than 100nm. The goal ofthis study was to consider the role of nanoscale topographic modificationof titanium substrates for the purpose of improvingosseointegration. Nanotechnology offers engineers and biologistsnew ways of interacting with relevant biological processes.Moreover, nanotechnology has provided means of understandingand achieving cell specific functions. The various techniquesthat can impart nanoscale topographic features to titaniumendosseous implants are described. Existing data supportingthe role of nanotopography suggests that critical steps in osseointegrationcan be modulated by nanoscale modification ofthe implant surface. Important distinctions between nanoscaleand micron-scale modification of the implant surface are presentlyconsidered. The advantages and disadvantages of nanoscalemodification of the dental implant surface are discussed.Finally, available data concerning the current dental implantsurfaces that utilize nanotopography in clinical dentistry aredescribed. Nanoscale modification of titanium endosseous implantsurfaces can alter cellular and tissue responses that maybenefit osseointegration and dental implant therapy. In a seriesof in vitro and in vivo experiments it was possible to evaluatethe effect of this modifications in different study designs. Theadvantages of the use of nanocues added to the surface of theosseointegrated dental implants allowed to a better and fasterosseointegration response of these materials, by acting on thedifferentiation of the osteoblasts.

The effects of implant surface nanoscale features on osteoblast-specific gene expression.

This study investigated the influence of nanoscale implant surface features on osteoblast differentiation. Titanium disks (20.0 x 1.0 mm) with different nanoscale materials were prepared using sol-gel-derived coatings and characterized by scanning electron microscopy, atomic force microscopy and analyzed by X-ray Photoelectron Spectrometer. Human Mesenchymal Stem Cells (hMSCs) were cultured on the disks for 3-28 days. The levels of ALP, BSP, Runx2, OCN, OPG, and OSX mRNA and a panel of 76 genes related to osteogenesis were evaluated. Topographical and chemical evaluation confirmed nanoscale features present on the coated surfaces only. Bone-specific mRNAs were increased on surfaces with superimposed nanoscale features compared to Machined (M) and Acid etched (Ac). At day 14, OSX mRNA levels were increased by 2-, 3.5-, 4- and 3-fold for Anatase (An), Rutile (Ru), Alumina (Al), and Zirconia (Zr), respectively. OSX expression levels for M and Ac approximated baseline levels. At days 14 and 28 the BSP relative mRNA expression was significantly up-regulated for all surfaces with nanoscale coated features (up to 45-fold increase for Al). The PCR array showed an up-regulation on Al coated implants when compared to M. An improved response of cells adhered to nanostructured-coated implant surfaces was represented by increased OSX and BSP expressions. Furthermore, nanostructured surfaces produced using aluminum oxide significantly enhanced the hMSC gene expression representative of osteoblast differentiation. Nanoscale features on Ti implant substrates may improve the osseointegration response by altering adherent cell response.