160 research outputs found
Fault diagnosis of a granulator operating under time-varying conditions using canonical variate analysis
Granulators play a key role in many pharmaceutical processes because they are involved in the production of tablets and capsule dosage forms. Considering the characteristics of the production processes in which a granulator is involved, proper maintenance of the latter is relevant for plant safety. During the operational phase, there is a high risk of explosion, pollution, and contamination. The nature of this process also requires an in-depth examination of the time-dependence of the process variables. This study proposes the application of canonical variate analysis (CVA) to perform fault detection in a granulation process that operates under time-varying conditions. Beyond this, a different approach to the management of process non-linearities is proposed. The novelty of the study is in the application of CVA in this kind of process, because it is possible to state that the actual literature on the theme shows some limitations of CVA in such processes. The aim was to increase the applicability of CVA in variable contexts, with simple management of non-linearities. The results, considering process data from a pharmaceutical granulator, showed that the proposed approach could detect faults and manage non-linearities, exhibiting future scenarios for more performing and automatic monitoring techniques of time-varying processes
Fault detection, diagnosis, and prognosis of a process operating under time-varying conditions
In the industrial panorama, many processes operate under time-varying conditions. Adapt¬ing high-performance diagnostic techniques under these relatively more complex situations is ur¬gently needed to mitigate the risk of false alarms. Attention is being paid to fault anticipation, requiring an in-depth study of prediction techniques. Predicting remaining life before the occurrence of faults allows for a comprehensive maintenance management protocol and facilitates the wear management of the machine, avoiding faults that could permanently compromise the integrity of such machinery. This study focuses on canonical variate analysis for fault detection in processes operating under time-varying conditions and on its contribution to the diagnostic and prognostic analysis, the latter of which was performed with machine learning techniques. The approach was validated on actual datasets from a granulator operating in the pharmaceutical sector
Monitoring a reverse osmosis process with kernel principal component analysis: A preliminary approach
The water purification process is becoming increasingly important to ensure the continuity and quality of subsequent production processes, and it is particularly relevant in pharmaceutical contexts. However, in this context, the difficulties arising during the monitoring process are manifold. On the one hand, the monitoring process reveals various discontinuities due to different characteristics of the input water. On the other hand, the monitoring process is discontinuous and random itself, thus not guaranteeing continuity of the parameters and hindering a straightforward analysis. Consequently, further research on water purification processes is paramount to identify the most suitable techniques able to guarantee good performance. Against this background, this paper proposes an application of kernel principal component analysis for fault detection in a process with the above-mentioned characteristics. Based on the temporal variability of the process, the paper suggests the use of past and future matrices as input for fault detection as an alternative to the original dataset. In this manner, the temporal correlation between process parameters and machine health is accounted for. The proposed approach confirms the possibility of obtaining very good monitoring results in the analyzed context
The occurrence of mycorrhizal fungi in Betula aetnensis Raf. roots: from ecological role to conservation strategies
Betula aetnensis Raf. is an endemic tree species of particular conservation value. It only
thrives in the north-eastern slopes of Mount Etna (Sicily), from 1200 to 2100 m a.s.l. This pioneer
plant is able to begin primary succession on nutrient-poor and water-limited soils (C = 0.17%;
N = 0.05 \u2030; P2O5 = 4.1 ppm), where beneficial mycorrhizal fungi (MF) may play a crucial role.
In order to investigate MF role in B. aetnensis, plant roots from natural sites and nursery grown
specimens were analyzed for both ectomycorrhizal and endomycorrhizal structures. Typical
structures of both symbiosis were detected by root staining and morphological observations.
Ectomycorrhizae (EM) were more abundant in natural sites ( 4888%) than in nursery ( 4877%).
Clear morphological differences in the EM root tips suggest the occurrence of different fungal
species. About 50% of roots had arbuscular structures, both in natural habitats and nursery. The
community structure of EM and AM fungal symbionts was characterized by DGGE analysis.
Mycorrhizal dependence trials are in progress to elucidate the relative importance of ectoand
endomycorrhizal symbionts for this endemism, whose conservation could be strongly linked
to mutualistic associations established at root level
Bacterial biofilms on biopolymeric sorbent supports for environmental bioremediation
Bioremediation encompasses a broad range of environmental biotechnology, which require
multidisciplinary approaches through implementation of innovative tools to the natural biological
process occurring in soil, water and air. Immobilization of hydrocarbon-degrading microorganisms
on biodegradable sorbent supports significantly promotes bioremediation processes. Recently
ecofriendly, low cost bioremediation devices based on polylactic acid (PLA) and polycaprolactone
(PCL) membranes hosting a biodegrading bacterial biofilms were obtained[1]. This work
investigates the higher effectiveness of immobilizing hydrocarbon-degrading bacteria compared to
that of planktonic cells. Soil hydrocarbon (HC) degrading Actinobacteria Nocardia cyriacigeorgica
strain SoB, Gordonia amicalis strain SoCg[2], and the marine hydrocarbonoclastic Alcanivorax
borkumensis strain AU3-AA-7[3] were immobilized on PLA and PCL membranes and tested on
hexadecane. The capacity of adhesion and proliferation of these biodegrading biofilms within
the biopolymers were evaluated at various time points (5, 10, 15, and 30 incubation days) using
scanning electron microscopy (SEM). The SEM images revealed that PLA and PCL nanofibers
were nearly completely covered by a complex three-dimensional bacterial film for all tested
strains. Quantification of total biomass (estimated as total dsDNA) confirmed biofilm growth up to
30 days of incubation. Crude oil biodegradation ability of biofilms-membranes systems, assessed
by Gas Chromatography-FID analysis, demonstrated the removal of over 60% of the oil after 5
days of incubation, outperforming free-living bacteria by 24%. Viable plate counts showed that
bacterial biofilms adsorbed on biopolymers were still viable after 30 days, indicating their potential
for long-term applications
Comparative Genomics Analysis of a New Exiguobacterium Strain from Salar de Huasco Reveals a Repertoire of Stress-Related Genes and Arsenic Resistance
Indexación: Web of Science; Scopus.The Atacama Desert hosts diverse ecosystems including salt flats and shallow Andean lakes. Several heavy metals are found in the Atacama Desert, and microorganisms growing in this environment show varying levels of resistance/tolerance to copper, tellurium, and arsenic, among others. Herein, we report the genome sequence and comparative genomic analysis of a new Exiguobacterium strain, sp. SH31, isolated from an altiplanic shallow athalassohaline lake. Exiguobacterium sp. SH31 belongs to the phylogenetic Group II and its closest relative is Exiguobacterium sp. S17, isolated from the Argentinian Altiplano (95% average nucleotide identity). Strain SH31 encodes a wide repertoire of proteins required for cadmium, copper, mercury, tellurium, chromium, and arsenic resistance. Of the 34 Exiguobacterium genomes that were inspected, only isolates SH31 and S17 encode the arsenic efflux pump Acr3. Strain SH31 was able to grow in up to 10 mM arsenite and 100 mM arsenate, indicating that it is arsenic resistant. Further, expression of the ars operon and acr3 was strongly induced in response to both toxics, suggesting that the arsenic efflux pump Acr3 mediates arsenic resistance in Exiguobacterium sp. SH31.http://journal.frontiersin.org/article/10.3389/fmicb.2017.00456/ful
The ferric iron uptake regulator (Fur) from the extreme acidophile Acidithiobacillus ferrooxidans
Indexación: Scopus.Acidithiobacillus ferrooxidans is a Gram-negative bacterium that lives at pH 2 in high concentrations of soluble ferrous and ferric iron, making it an interesting model for understanding the biological mechanisms of bacterial iron uptake and homeostasis in extremely acid conditions. A candidate furAF (Ferric Uptake Regulator) gene was identified in the A. ferrooxidans ATCC 23270 genome. FurAF has significant sequence similarity, including conservation of functional motifs, to known Fur orthologues and exhibits cross-reactivity to Escherichia coli Fur antiserum. The furAF gene is able to complement fur deficiency in E. coli in an iron-responsive manner. FurAF is also able to bind specifically to E. coli Fur regulatory regions (Fur boxes) and to a candidate Fur box from A. ferrooxidans, as judged by electrophoretic mobility shift assays. FurAF represses gene expression from E. coli Fur-responsive promoters fiu and fhuF when expressed at high protein levels. However, it increases gene expression from these promoters at low concentrations and possibly from other Fur-regulated promoters involved in iron-responsive oxidative stress respon.https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.27581-
Restoration practices in Mediterranean habitats using native woody species
Since the beginning of the XXI century, Legambiente (a national environmental association), supported by the University of Palermo, has launched several naturalization projects within three Sicilian nature reserves:
1)Isola di Lampedusa (Agrigento Province);
2)Macalube di Aragona (Agrigento Province);
3)Lago Sfondato (Caltanissetta Province). Interventions were carried out on bare lands and degraded sites where natural vegetation cover was almost completely disappeared. The main aim was to restore native habitats following the principles of ecological restoration. Accordingly, differently from the classical approach, consisting in the use of preparatory species, usually Pines, native shrubs and trees were selected and used in the field
Restoration practices in Mediterranean habitats using native woody species
Since the beginning of the XXI century, Legambiente (a national environmental association), supported by the University of Palermo, has launched several naturalization projects within three Sicilian nature reserves:
1)Isola di Lampedusa (Agrigento Province);
2)Macalube di Aragona (Agrigento Province);
3)Lago Sfondato (Caltanissetta Province). Interventions were carried out on bare lands and degraded sites where natural vegetation cover was almost completely disappeared. The main aim was to restore native habitats following the principles of ecological restoration. Accordingly, differently from the classical approach, consisting in the use of preparatory species, usually Pines, native shrubs and trees were selected and used in the field
- …