12 research outputs found
Rotor Unbalance Kind and Severity Identification by Current Signature Analysis with Adaptative Update to Multiclass Machine Learning Algorithms
The health of a rotating electric machine can be evaluated by monitoring electrical and mechanical parameters. As more information is available, it easier can become the diagnosis of the machine operational condition. We built a laboratory test bench to study rotor unbalance issues according to ISO standards. Using the electric stator current harmonic analysis, this paper presents a comparison study among Support-Vector Machines, Decision Tree classifies, and One-vs-One strategy to identify rotor unbalance kind and severity problem – a nonlinear multiclass task. Moreover, we propose a methodology to update the classifier for dealing better with changes produced by environmental variations and natural machinery usage. The adaptative update means to update the training data set with an amount of recent data, saving the entire original historical data. It is relevant for engineering maintenance. Our results show that the current signature analysis is appropriate to identify the type and severity of the rotor unbalance problem. Moreover, we show that machine learning techniques can be effective for an industrial application
Fungal endophytes from arid areas of Andalusia: high potential sources for antifungal and antitumoral agents
Native plant communities from arid areas present distinctive characteristics to survive in extreme
conditions. The large number of poorly studied endemic plants represents a unique potential
source for the discovery of novel fungal symbionts as well as host-specific endophytes not yet
described. The addition of adsorptive polymeric resins in fungal fermentations has been seen to
promote the production of new secondary metabolites and is a tool used consistently to generate
new compounds with potential biological activities. A total of 349 fungal strains isolated from 63
selected plant species from arid ecosystems located in the southeast of the Iberian Peninsula, were
characterized morphologically as well as based on their ITS/28S ribosomal gene sequences. The fungal
community isolated was distributed among 19 orders including Basidiomycetes and Ascomycetes,
being Pleosporales the most abundant order. In total, 107 different genera were identified being
Neocamarosporium the genus most frequently isolated from these plants, followed by Preussia and
Alternaria. Strains were grown in four different media in presence and absence of selected resins to
promote chemical diversity generation of new secondary metabolites. Fermentation extracts were
evaluated, looking for new antifungal activities against plant and human fungal pathogens, as well
as, cytotoxic activities against the human liver cancer cell line HepG2. From the 349 isolates tested,
126 (36%) exhibited significant bioactivities including 58 strains with exclusive antifungal properties
and 33 strains with exclusive activity against the HepG2 hepatocellular carcinoma cell line. After LCMS
analysis, 68 known bioactive secondary metabolites could be identified as produced by 96 strains,
and 12 likely unknown compounds were found in a subset of 14 fungal endophytes. The chemical
profiles of the differential expression of induced activities were compared. As proof of concept, ten
active secondary metabolites only produced in the presence of resins were purified and identified. The
structures of three of these compounds were new and herein are elucidated.This work was supported by Fundación MEDINA and the Andalusian Government grant
RNM-7987 ‘Sustainable use of plants and their fungal parasites from arid regions of Andalucía for new molecules
useful for antifungals and neuroprotectors’
The challenging combination of intense fluorescence and high singlet oxygen quantum yield in photostable chlorins : a contribution to theranostics
High
fl
uorescence quantum yields, high singlet oxygen quantum yields and intense absorptions in the
phototherapeutic window are fundamental properties for compounds intended for
fl
uorescence diagno-
sis and photodynamic therapy. We report on photostable chlorins that combine these properties. The
fl
uorinated tetraphenylchlorin FCMet has
Φ
F
= 0.396 and
Φ
Δ
= 0.58 ± 0.07, whereas F
2
CMet has
Φ
F
=
0.360 and
Φ
Δ
= 0.54 ± 0.05, and both have molar absorption coe
ffi
cients larger than 30000 M
−
1
cm
−
1
above 650 nm. These dual functional agents use nearly all the energy absorbed to perform the desired
functions and are appropriate for theranostics applications
Corallopyronin A Specifically Targets and Depletes Essential Obligate Wolbachia Endobacteria From Filarial Nematodes In Vivo
Doxycycline and rifampicin deplete essential Wolbachia from filarial nematodes that cause lymphatic filariasis or onchocerciasis, resulting in blocked worm development and death. However, doxycycline is contraindicated for children and pregnant/breastfeeding women, as is rifampicin in the latter group with the additional specter of possible resistance development in Mycobacterium spp. Novel antibiotics with a narrower spectrum would aid in eliminating filarial diseases. Corallococcus coralloides synthesizes corallopyronin A, a noncompetitive inhibitor of RNA polymerase ineffective against Mycobacterium spp. Corallopyronin A depleted Wolbachia from infected insect cells (1.89 Thus the antibiotic is effective against intracellular bacteria despite the many intervening surfaces (blood vessels, pleura, worm cuticle) and membranes (worm cell, vesicle, Wolbachia inner and outer membranes). Corallopyronin A is an antibiotic to develop further for filariasis elimination without concern for cross-resistance development in tuberculosis
Ultrafast Dynamics of Manganese(III), Manganese(II), and Free-Base Bacteriochlorin: Is There Time for Photochemistry?
Manganese(III) and
manganese(II) complexes of halogenated sulfonamide
tetraphenylbacteriochlorins were prepared for the first time via a
transmetalation reaction and shown to be stable at room temperature.
The behavior of the electronic states of the paramagnetic complexes
is remarkably different from those of the metal-free bacteriochlorins
or diamagnetic metallobacteriochlorins. The Mn<sup>3+</sup> complex
exhibits eight electronic transitions between different states from
300 to 1100 nm, with a very prominent band (molar absorption coefficient
of ca. 50000 M<sup>–1</sup> cm<sup>–1</sup>) at 829
nm. Ultrafast transient absorption showed the formation of an excited
singquintet state that decays to a tripquintet state with a femtosecond
lifetime. The tripquintet state decays in 5 ps, yielding a tripseptet
state with a 570 ps lifetime. The electronic absorption of the Mn<sup>2+</sup> complex more closely resembles those of diamagnetic metallobacteriochlorins,
but the longest decay lifetime is only ca. 8 ps. The intense photoacoustic
waves generated with near-infrared excitation suggest the use of these
complexes in photoacoustic tomography
Heterologous Expression, Biosynthetic Studies, and Ecological Function of the Selective Gq-Signaling Inhibitor FR900359
The cyclic depsipeptide FR900359 (FR), isolated from the tropical plant Ardisia crenata, is a strong and selective inhibitor of Gq proteins, making it an indispensable pharmacological tool to study Gq-related processes, as well as a promising drug candidate. Gq inhibition is a novel mode of action for defense chemicals and crucial for the ecological function of FR, as shown by in vivo experiments in mice, its affinity to insect Gq proteins, and insect toxicity studies. The uncultured endosymbiont of A. crenata was sequenced, revealing the FR nonribosomal peptide synthetase (frs) gene cluster. We here provide a detailed model of FR biosynthesis, supported by in vitro enzymatic and bioinformatic studies, and the novel analogue AC-1, which demonstrates the flexibility of the FR starter condensation domains. Finally, expression of the frs genes in E. coli led to heterologous FR production in a cultivable, bacterial host for the first time