MIBiG 3.0: a community-driven effort to annotate experimentally validated biosynthetic gene clusters

Microbial Biotechnolog

Gas sensing properties of Nd2O3 nanostructured microspheres

Nd2O3 microspheres were prepared by a solution-coprecipitation method. The dissolution of neodymium nitrate in formic acid produced, at room temperature, semispherical particles of neodymium formate (Nd(HCOO)3). The size of these particles was in the range 0.5 to 1.4 ?m. The thermal decomposition at 600 C transformed Nd(HCOO)3 to single-phase Nd2O3, with cubic crystal structure. A decrease of size of ~15% also took place. A detailed inspection of their surface revealed the formation of a sponge-like solid, possessing extensive nanoporosity. The gas sensing characterization was performed on thick films made with the as-prepared Nd2O3 microspheres. Based in the response to the test gases an n-type semiconductor behavior was observed. A reliable detection of CO was observed from 300 C, using an applied frequency of 100 kHz; however, better results were obtained at 400 C. For CO2, the best results were registered at 400 C and 100 kHz; whereas in ethanol vapor these were obtained at lower temperature and frequency (300 C and 100 Hz). Quantitative detection of CO and ethanol vapor was achieved; however, the results were not satisfactory for CO2. 2013 Elsevier B.V

Gas sensing properties of nanostructured bismuth oxychloride

In this work, nanostructured bismuth oxychloride (BiOCl) was prepared by a surfactant-assisted method. Bismuth trichloride and dioctyl sulfosuccinate (AOT) were dissolved in non-aqueous media, producing a fine precipitate. The calcination of the precipitated particles at 180 �C produced 3D hierarchical BiOCl semi-spherical architectures, assembled by microplates. The increase of the calcination temperature to 600 �C produced nanostructured ribbons, which are formed by the stacking of several BiOCl layers. Other microstructures can be formed at different calcination temperatures or by using other surfactants. Thick-films of the as-prepared BiOCl ribbons were made by its direct deposition on alumina substrates. The gas sensing characterization was performed at 300 and 400 �C using alternating current (AC). The tests gases were compressed air, CO, CO2 and O2. Humidity effects were discarded by using the extra dry version of these gases. At 300 �C, reproducible CO gas sensing patterns were obtained; however, the detection of CO2 and O 2 produced unreliable results. At 400 �C, reliable gas sensing patterns were obtained in CO, CO2 and O2. According to its gas response, BiOCl behaved as a p-type seminconductor material. � 2011 Elsevier B.V. All rights reserved

Modelling bioaccumulation of semi-volatile organic compounds (SOCs) from air in plants based on allometric principles

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Biological versus chemical control of fall armyworm and Lepidoptera stem borers of maize (Zea mays)

Insect pests are serious constraints to production of maize. There is little information on the control measures against those insects in Cameroon. This study was carried out to identify the different species of fall armyworm and stem borers of maize and test the efficacy of different control methods. The maize variety ATP (Acid Tolerant Population) was used in a randomized complete block design. Synthetic insecticides, lambda cyalothrine and cypermethrin, were applied at one and two weeks intervals at the recommended doses of 2 L/ha and 1.5 l/ha respectively. Bio insecticides: Neem oil (Azadirachta indica), and aqueous extracts of Chenopodium ambrosioides leaves were applied weekly at the doses of 1.40 L/ha and 6.80 L/ha respectively. The different larvae recorded were the fall armyworm (Spodoptera frugiperda) and stem borers (Busseola fusca and Sesamia calamistis). All the treatments used in this study had significant effects on the number of pupae, the tunnels and the number of perforations on stems of the maize. The Neem oil at one-week interval was more effective in reducing the incidence (81, 21%) and severity (61, 54%) at 76 Days After Planting of the attack by the caterpillars as well as on the number of larvae (14, 82%) throughout the trial

Colorful protein-based fluorescent probes for collagen imaging

Real-time visualization of collagen is important in studies on tissue formation and remodeling in the research fields of developmental biology and tissue engineering. Our group has previously reported on a fluorescent probe for the specific imaging of collagen in live tissue in situ, consisting of the native collagen binding protein CNA35 labeled with fluorescent dye Oregon Green 488 (CNA35-OG488). The CNA35-OG488 probe has become widely used for collagen imaging. To allow for the use of CNA35-based probes in a broader range of applications, we here present a toolbox of six genetically-encoded collagen probes which are fusions of CNA35 to fluorescent proteins that span the visible spectrum: mTurquoise2, EGFP, mAmetrine, LSSmOrange, tdTomato and mCherry. While CNA35-OG488 requires a chemical conjugation step for labeling with the fluorescent dye, these protein-based probes can be easily produced in high yields by expression in E. coli and purified in one step using Ni2+-affinity chromatography. The probes all bind specifically to collagen, both in vitro and in porcine pericardial tissue. Some first applications of the probes are shown in multicolor imaging of engineered tissue and two-photon imaging of collagen in human skin. The fully-genetic encoding of the new probes makes them easily accessible to all scientists interested in collagen formation and remodeling