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Natural based-cellulosic fibers are trending due to the global awareness regarding environmental health and because their properties make them a great alternative to the synthetic fibers. However, these fibers also have some hindrances that can be solved with their functionalization. The present study concerns modification of the surface of natural based-cellulosic fibers extracted from stems of the ginger lily plant (Hedychium gardnerianum) with TiO2 films deposited by DC magnetron sputtering using a titanium (Ti) target. A detailed characterization of the TiO2-coated fibers was investigated by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results revealed that the sputtered TiO2 films can be attached to the ginger lily fibers mainly by their OH groups. XPS analysis further shows that C–OH group is not dominant, which means that no pure cellulose is present at the surface.

Hedychium gardnerianum Sheph. ex Ker Gawl. is one of the 100 world's worst invasive alien species and the research target in areas as diverse as biological control, natural fibres uses, taxonomy or the biological activity of its compounds. This review aimed to clarify the taxonomic status and the native range of H. gardnerianum and bring accuracy to the history of its introduction and escape from cultivation through the analysis of the increasing number of accessible digitalized dry specimens and grey literature. The analysis of the available information allowed to conclude that: (a) Hedychium gardnerianum is a validly published name, the authority of the name is Sheph. ex Ker Gawl., the species holotype is the illustration published along with the species name, and the Natural History Museum BM000574691 specimen collected in 1815 is the first dried specimen of H. gardnerianum; (b) This species is native to the Central and Eastern Nepal, Bhutan, Northeast India and North Myanmar; (c) The species was cultivated at Cambridge Botanical Garden since 1818 and the first known herbarium specimen collected in Europe dates back to 1821; (d) Kathmandu (Nepal) and Khasi Hills (India) specimens are considered two varieties of the same species and the BM000574691 specimen is the lectotype of H. gardnerianum var. speciosum; (e) Specimens, references, and/or pictures support that H. gardnerianum escaped from cultivation at Galicia (Spain), Azores archipelago, Madeira, Tenerife, Cuba, Jamaica, Martinique, Trinidad, Ascension, Mexico, Honduras, Brazil, South Africa, Swaziland, Zimbabwe, Réunion, Mauritius, Australia, New Zealand, Fiji, Hawaii, and Vietnam; and (f) H. gardnerianum is a serious pest in Azores, Madeira, Jamaica, Réunion, New Zealand and Hawaii and continues to expand its distribution area in South and Central America, Australia and Southern Africa. This review presents linear raw information compiled with precision, allowing the world databases updating their data but also gives the most detailed information possible to each country/region identifying new regions of concern and updating the invasiveness status in each region.

The surface functionalization of natural fibers, mainly using TiO2 films, shows a growing interest in its application as yarns in fabrics that require advanced properties, allowing the use of their excellent physical and chemical properties in the textile area. The DC magnetron sputtering technique is a potential method for depositing TiO2 films onto natural fibers, allowing for the creation of advanced and competitive properties compared to synthetic fibers. Different crystalline phases of TiO2 have been shown to be effective in photocatalytic applications. Reactive discharges like the Ar/O2 gas mixture can be used to deposit TiO2 films with desired characteristics, and controlling deposition parameters can further manipulate the properties of the coatings. Analytical techniques such as XRD, XPS, and SEM/EDS can be used to study the surface properties of TiO2 films. XRD determines crystal structure, XPS provides information on chemical composition, and SEM/EDS examines morphology and elemental composition.

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This study aimed to identify the key factors influencing the phytoplankton development in four lakes on the island of São Miguel (Azores). We used a multivariate analysis of biological parameters (phytoplankton), physicochemical parameters, and meteorological data. Data were collected between 2003 and 2018 in the volcanic Lakes of Sete Cidades (Green and Blue), Fogo, and Furnas. The ecosystems of these bodies of water are increasingly vulnerable to anthropogenic activities (increasing human pressure) as well as to changing climate patterns. This analysis is the first exploratory approach to this dataset to explore trends and patterns of evolution from a multivariate perspective. This approach is also intended to improve understanding of the conditions that favor the emergence of different Cyanobacterial divisions. For this purpose, several statistical and chemometric methods were used, such as analysis of variance (ANOVA) and principal component analysis (PCA). Multivariate models combining biological and meteorological data focused from 2010 to 2012. The results from the PCA models showed that the abundance of Bacillariophyta, Dinophyta, and Cryptophyta phyla are correlated and appear to be influenced by high levels of precipitation, evaporation, and wind speed. On the other hand, the Cyanophyta, Chlorophyta, and Chrysophyta phyla appear to be more correlated with high values of air temperature, water temperature, and radiation. Also, the Euglenophyta phylum appears to be associated with low levels of precipitation, evaporation and wind speed, and high temperatures. Finally, we can conclude that these lakes have endured physicochemical parameters over the past 15 years, meaning that the measures adopted to monitor and protect the lakes are effective.

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