Search results for "fire"
showing 10 items of 463 documents
Cementing agents involved in the macro- and microaggregation of a Mediterranean shrubland soil under laboratory heating
2014
The heating effect on aggregation and cementing agents of a Mediterranean soil was studied in two fractions (macro- and microaggregates) in different environments: under Quercus coccifera soil (UQ), under Rosmarinus officinalis soil (UR) and between plants or bare soil (BS). Samples were heated under laboratory conditions at different temperatures (220, 380, 500, 750 and 1000. °C) to establish their effects on the studied soil properties by comparison with unheated control samples (25. °C). Increasing temperature treatments caused significant changes in most soil variables. In both soil fractions, the presence of vegetation contributed to increase of the soil organic matter (SOM) content, w…
Determination of selected polyaromatic hydrocarbons by gas chromatography–mass spectrometry for the analysis of wood to establish the cause of sinkin…
2014
Abstract The aim of this paper was to establish the cause of sinking of an old wooden vessel by polycyclic aromatic hydrocarbon (PAH) analyses because wood combustion is a source of PAHs. In particular, the molecular PAH patterns generated by each source are like fingerprints and it is possible to determine the processes that generate PAHs by studying their distribution in wood samples. The relative abundance of high molecular weight PAHs, together with the PAH compound ratios and with total index (proposed by us) has demonstrated that samples owe their PAHs in wood archaeological material to a predominant single mode of origin, i.e. combustion processes, therefore we can say that the sinki…
Exopolysaccharides favor the survival of Erwinia amylovora under copper stress through different strategies.
2010
Erwinia amylovora causes fire blight, a destructive disease of rosaceous plants very difficult to control. We demonstrated that copper, employed to control plant diseases, induces the "viable-but-nonculturable" (VBNC) state in E. amylovora. Moreover, it was previously reported that copper increases production of its main exopolysaccharide (EPS), amylovoran. In this work, the copper-complexing ability of amylovoran and levan, other major EPS of E. amylovora, was demonstrated. Following this, EPS-deficient mutants were used to determine the role of these EPSs in survival of this bacterium in AB mineral medium with copper, compared to their wild type strain and AB without copper. Tot…
Multiscale variation in drought controlled historical forest fire activity in the boreal forests of eastern Fennoscandia
2017
Forest fires are a key disturbance in boreal forests, and characteristics of fire regimes are among the most important factors explaining the variation in forest structure and species composition. The occurrence of fire is connected with climate, but earlier, mostly local-scale studies in the northern European boreal forests have provided little insight into fire-climate relationship before the modern fire suppression period. Here, we compiled annually resolved fire history, temperature, and precipitation reconstructions from eastern Fennoscandia from the mid-16th century to the end of the 19th century, a period of strong human influence on fires. We used synchrony of fires over the network…
A Methodology for Protection of Trees Against Lightning Strikes as a Measure to Prevent Fires and Loss of Human Life
2021
Some regions may be characterized by a very low annual lightning ground flash density, and yet lightning strikes seem to have been in those areas the cause of widespread wildfires in forested areas. Due to global climate change, these occurrences seem to be an increasing threat. In this paper, the authors discuss the withstand capability of trees against lightning and introduce the criteria for the deployment of tree lightning protection systems (TLPS) to protect forested areas, where deemed necessary by the tree risk assessment. This work analytically identifies the critical trunk radius of the tree below which the tree may explode in the case of a lightning strike and ignite the surroundi…
Preservation in Disaster Situations: a case study of the Valvilla Wool Mill Museum, Finland
2013
This article discusses the role of documentation and rescue planning in minimizing collection damages in disaster situations. The topic is surveyed through a case study of a fire that occurred in 2003 at the Valvilla Wool Mill museum in Hyvinkää, in Southern Finland. This incident caused significant damage to the authenticity and integrity of the museum’s archival collection. Both the fire and the extinguishing of the fire caused severe damage to items in the archival collection. Deterioration continued during aftercare, causing serious secondary collection damage because the methods of the first aid and aftercare were spontaneously planned and applied. By using the Valvilla Wool Mill museu…
Profesionālās izaugsmes vietne studentiem un absolventiem
2022
Kvalifikācijas darba mērķis ir izstrādāt tīmekļa vietni, kas dotu iespēju studentiem un absolventiem viegli un efektīvi atrast darba vietu, lai gūtu pieredzi nākotnei. Lietotnē ir divi galvenie lietotāji – uzņēmumi un studenti. Uzņēmumus apstiprina administrators, bez apstiprināšanas nav iespējams pievienot jaunus darba sludinājumus. Apstiprināti uzņēmuma tipa lietotāji var pievienot savu uzņēmumu un veidot jaunus darba sludinājumus, bet studenta tipa lietotāji var tiem pieteikties. Uzņēmumi var apstiprināt vai noraidīt studentu pieteikumus. Ja pieteikumu apstiprina, tad parādās studenta kontakti, lai uzņēmums varētu sazināties un sākt sadarbību. Projekts sastāv no 4 moduļiem – lietotāju, d…
Deju kolektīvu sistēmas Adance android lietotne
2016
“Adance” Android lietotne ir papildinājums deju kolektīvu pārvaldības un informācijas sistēmai “Adance”. Šajā darbā izstrādātais Android klients ietver sevī sistēmas tūlītējās saziņas pakalpojumu, kura izstrādes procesam līdztekus arī tika izveidota sistēmas publiskā lietojumprogrammas saskarne (API). Lietotājiem ir iespēja piekļūt savām sarunām ar citiem kolektīvu dalībniekiem, lasīt savas ziņas reāllaikā, kad tās pienāk, kā arī izveidot jaunas sarakstes, lai uzturētu kontaktu ar saviem kolektīva biedriem.
Topical anti-inflammatory potential of quercetin in lipid-based nanosystems: In vivo and in vitro evaluation
2013
Purpose: To develop quercetin-loaded phospholipid vesicles, namely liposomes and PEVs (Penetration Enhancer-containing Vesicles), and to investigate their efficacy on TPA-induced skin inflammation. Methods: Vesicles were made from a mixture of phospholipids, quercetin and polyethylene glycol 400 (PEG), specifically added to increase drug solubility and penetration through the skin. Vesicle morphology and self-assembly were probed by Cryo-Transmission Electron Microscopy and Small/Wide Angle X-ray Scattering, as well as the main physico-chemical features by Light Scattering. The anti-inflammatory efficacy of quercetin nanovesicles was assessed in vivo on TPA-treated mice dorsal skin by the d…
Heat-resistant unfired phosphate ceramics with carbon nanotubes for electromagnetic application
2014
Composite materials, containing low concentrations of carbon nanotubes (CNTs) of three different diameters and heat-resistant phosphate ceramic as a matrix were prepared by cold-pressing method. Their dielectric properties were studied at room temperature in a wide frequency range (20 Hz–1 MHz). It was found experimentally and proved theoretically via modeling of the composites as a random capacitor–resistor–diode network that electrical percolation concentration depends significantly on the diameter of the nanoinclusions. The main conclusion is that the best candidate providing both the lower percolation threshold and high absolute values of ac conductivity is thinner carbon nanotubes (in …