12 research outputs found
Microplastics and Associated Microorganisms in the Sea Sediment of the Sentina Regional Natural Reserve (Central Adriatic Sea, Italy)
(1) Background: The large dispersion of microplastics (MPs) in the marine environment has effects on the health of living organisms [1,2,3]. The aim of this study was to identify MPs and their associated microorganisms in Adriatic Sea sediments and to evaluate the antibiotic susceptibility patterns of the microbial communities. (2) Methods: A beach transect, parallel to the shoreline where the waves break, was identified for the samplings. A protocol to perform MP isolation from sandy sediments at different seasons, suitable for biological sample upkeeping, and based on plastic floating in high salinity water, was optimized. From floating MPs, aerobic and anaerobic cultivable microorganisms were isolated and total DNA extraction was performed for the shotgun metagenomic analysis. Susceptibility to a panel of 14 antibiotics, belonging to 12 different categories, was assessed [4,5]. Chemical characteristics of the isolated MPs were analysed using a Thermo Nicolet 6700 FT-IR Spectrometer with âSmart Orbitâ diamond micro-ATR accessory and Thermo Nicolet iN10 MX FT-IR microscope. (3) Results: Via chemical analysis, polypropylene microplastics were estimated in the highest percentage, followed by polyethylene, poly-methyl acrylate, and poly-vinyl chloride. Metagenomics data revealed differences in bacterial abundances during seasons and in floating MPs with respect to total sand. The differential gene analysis showed specific metabolic pathways in MP-associated microorganisms, including antibiotic resistance. Via microbial cultivation and MALDI-TOF MS identification, bacteria that are promising for plastic degradation, such as Lysinobacillus fusiformis, Exiguobacterium sp., and Pseudomonas oleovorans, were also found, as well as potential pathogens, like Clostridium septicum, Clostridium novyi, and Shewanella putrefaciens. Only 17.2% were found to be susceptible to all the tested antibiotics. High percentages of resistance were observed for penicillins (85.7%), monobactams (80.9%), and tetracyclines (64.3%). (4) Conclusions: MPs work as a vehicle for potential pathogens and antibiotic-resistant microorganisms in the Central Adriatic Sea
Multi-method Analysis of Avian Eggs as Grave Goods: Revealing Symbolism in Conversion Period Burials at Kukruse, NE Estonia
Eggshells are unusual finds in the Iron Age of eastern Europe (500 BCâ1200 AD) deserving extra attention in terms of analysis as well as interpretation. This paper discusses two rare eggshell finds, discovered in female burials at the conversion period (12thâ13th century AD) cemetery at Kukruse, NE Estonia. Our multianalytical study combining FT-IR, SEM(-EDS), microscopy and ZooMS provides an overview of methods applicable for identifying egg species, their predepositional history and curation. Based on the analytical results and the comparative analysis of the content and context of these two burials, we argue that different aims and connotations lay behind depositing eggs as burial goods, allowing well-supported interpretations of both pagan and Christian religious worldviews simultaneously
ATR-FT-IR spektroskoopia vĂ”imaluste laiendamine anorgaaniliste pigmentide analĂŒĂŒsimisel
VÀitekirja elektroonilisest versioonist puuduvad publikatsioonide tÀistekstid.The present work focused on expanding the possibilities and usefulness of micro-ATR-FT-IR spectroscopy in identification of different inorganic pigments in historic artefacts.
Most of the pigments used historically in paintings and other artefacts are inorganic compounds. ATR-FT-IR has found limited use for determination of inorganic pigments, because the mid-IR (4000â400 cmâ1) region of the IR spectrum of many of them is not characteristic enough and also there are many pigments that either do not absorb in that region at all (oxides, sulphides, etc) or have absorptions that are at the low wavenumber end of that region and are not characteristic enough for pigment identification. So, many pigment materials absorb IR radiation in the far-IR region (below 500 cmâ1). In contrast to the mid-IR region the far-IR region has traditionally been significantly less accessible for routine IR spectroscopic measurements. However, recent advances in instrument design have brought the wavenumber range below 500 cmâ1 well within reach of commercial FT-IR equipment. Nevertheless, this wavenumber region has up to now found almost no use in investigation of historic artefacts.
In this dissertation 47 most widespread inorganic red, white, yellow, blue, green, brown and black pigments were examined. An analytical method for determination and identification of these inorganic pigments in paint layers by micro-ATR-FT-IR using the wavenumber region of 550â230 cmâ1 was developed. The advantages and limitations of the ATR-FT-IR and developed analytical method of the analysis of inorganic pigments in the low wavenumber were discussed.
This work provides a comprehensive overview of the inorganic pigment identification possibilities using ATR-FT-IR as well as a collection of reference spectra in the low wavenumber range (550-230 cm-1) and is expected to be a useful reference material for conservation practitioners and material scientists. The usefulness of ATR-FT-IR in the region of 550-230 cm-1 for identification of inorganic pigments is demonstrated by 5 case studies on art objects (several of them are important in Estonian history).KÀesolevas doktoritöös keskenduti mikro-ATR-FT-IR spektroskoopia vÔimaluste hindamisele ja rakendusala laiendamisele erinevate anorgaaniliste pigmentide uurimisel.
Sajandeid on erinevate maalide maalimisel ja teiste kunstiobjektide kaunistamisel kasutatud vĂ€rvi koostises anorgaanilisi pigmente. FT-IR spektroskoopiat on piiratult kasutatud anorgaaniliste pigmentide analĂŒĂŒsimisel kuna IR spektris kesk-IR ala (4000â400 cmâ1) pole mitmete pigmentide mÀÀramisel kĂŒllalt karakteristlik, samuti on palju selliseid pigmente, mis ei neela ĂŒldse selles alas (oksiidid, sulfiidid) vĂ”i omavad neeldumisi, mis on keskmise IR ala lĂ”pus ja need ei ole kĂŒllalt karakteristlikud pigmendi tuvastamisel seguproovis. On teada, et paljud pigmendid neelavad kaug-IR piirkonnas (allpool 500 cm-1). Varem, kasutades tavalisi FT-IR spektromeetreid, oli vĂ”rreldes kesk-IR alaga kaug-IR alas mÔÔtmisi palju raskem teostada. TĂ€napĂ€eval uuemad FT-IR seadmed vĂ”imaldavad kasutada lainearvude piirkonda allpool 500 cm-1. Hoolimata sellest seda piirkonda kunstiobjektide uurimisel pole praktiliselt ĂŒldse kasutatud.
KĂ€esolevas doktoritöös uuriti 47 valget, kollast, punast, sinist, rohelist, pruuni ja musta pigmenti. Töötati vĂ€lja metoodika vĂ€rvikihtides pigmentide analĂŒĂŒsimiseks mikro-ATR-FTIR meetodil kasutades lainearvude vahemikku 550â230 cmâ1. Toodi vĂ€lja ATR-FT-IR spektroskoopia ja vĂ€ljatöötatud metoodika eelised ja puudused anorgaaniliste pigmentide uurimisel madalatel lainearvudel.
Doktoritöö annab ĂŒlevaate anorgaaniliste pigmentide uurimise vĂ”imalustest ATR-FT-IR-iga, samuti vĂ”rdlusspektrite kogumiku pigmentidest, mis neelavad madalatel lainearvudel (550â230 cmâ1). Viie rakendusnĂ€ite pĂ”hjal demonstreeriti ATR-FTIR meetodi kasulikkust tuvastada vĂ€rviproovides pigmenti kasutades lainearvude piirkonda 550-230 cm-1. RakendusnĂ€idete vĂ€rviproovid vĂ”eti kunstiobjektidelt, millest mitmed on Eesti kunstiajaloos olulisel kohal
ATR-FTIR spectroscopy and quantitative multivariate analysis of paints and coating materials
The applicability of ATR-FTIR spectroscopy with partial least squares (PLS) data analysis was evaluated for quantifying the components of mixtures of paint binding media and pigments, and alkyd resins. PLS methods were created using a number of standard mixtures. Validation and measurement uncertainty estimation was carried out. Binary, ternary and quaternary mixtures of several common binding media and pigments were quantified, with standard measurement uncertainties in most cases below 3g/100g. Classes of components - aromatic anhydrides and alcohols - used in alkyd resin synthesis were also successfully quantified, with standard uncertainties in the range of 2-3g/100g. This is a more demanding application because in alkyd resins aromatic anhydrides and alcohols have reacted to form a polyester, and are not present in their original forms. Once a PLS method has been calibrated, analysis time and cost are significantly reduced from typical quantitative methods such as GC/MS. This is beneficial in the case of routine analysis where the components are known
Quantitative GCâMS Analysis of Artificially Aged Paints with Variable Pigment and Linseed Oil Ratios
In this study, quantitative gas chromatographyâmass spectrometry (GCâMS) analysis was used to evaluate the influence of pigment concentration on the drying of oil paints. Seven sets of artificially aged self-made paints with different pigments (yellow ochre, red ochre, natural cinnabar, zinc white, Prussian blue, chrome oxide green, hematite + kaolinite) and linseed oil mixtures were analysed. In the pigment + linseed oil mixtures, linseed oil concentration varied in the range of 10 to 95 g/100 g. The results demonstrate that the commonly used palmitic acid to stearic acid ratio (P/S) to distinguish between drying oils varied in a vast range (from especially low 0.6 to a common 1.6) even though the paints contained the same linseed oil. Therefore, the P/S ratio is an unreliable parameter, and other criteria should be included for confirmation. The pigment concentration had a substantial effect on the values used to characterise the degree of drying (azelaic acid to palmitic acid ratio (A/P) and the relative content of dicarboxylic acids (âD)). The absolute quantification showed that almost all oil paint mock-ups were influenced by pigment concentration. Therefore, pigment concentration needs to be considered as another factor when characterising oil-based paint samples based on the lipid profile
Multi-method analysis of avian eggs as grave goods: revealing symbolism in conversion period burials at Kukruse, NE Estonia
Eggshells are unusual finds in the Iron Age of eastern Europe (500 BCâ1200 AD) deserving extra attention in terms of analysis as well as interpretation. This paper discusses two rare eggshell finds, discovered in female burials at the conversion period (12thâ13th century AD) cemetery at Kukruse, NE Estonia. Our multianalytical study combining FT-IR, SEM(-EDS), microscopy and ZooMS provides an overview of methods applicable for identifying egg species, their predepositional history and curation. Based on the analytical results and the comparative analysis of the content and context of these two burials, we argue that different aims and connotations lay behind depositing eggs as burial goods, allowing well-supported interpretations of both pagan and Christian religious worldviews simultaneously
The life and times of an estonian mesolithic slotted bone âdaggerâ. extended object biographies for legacy objects
All too often archaeological objects are found as stray finds. As such, they have little or no contextual information, which often makes them difficult to handle analytically and in terms of their exhibition appeal. As a consequence, they often languish un-researched in museum storerooms and there is the critical risk that such objects fall victim to the ongoing curation crisis and are deaccessioned due to a perceived lack of value. Therefore, in this paper we aim to illustrate the applicability of an extended biographical approach to such legacy material by studying the changing character of the Ulbi dagger, an Early Mesolithic flint-edged bone dagger, in its both archaeological and modern contexts. By using both a combination of traditional archaeological methods, coupled with a critical analysis of past illustrations, the dagger went from an isolated, undated, and unique object to a tool with a complex life history extending more than 9000 years. Our analysis reveals multiple stages of manufacturing and ornamentation including the presence of possible anthropomorphic figures. Use-wear analysis also allows us to address the objectâs likely primary function. Finally, we speculate about its deposition and discuss previously overlooked post-recovery episodes of damage and repair