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Wood-polymer hybrids demonstrate unique perspectives in green architecture, energy-efficiency building, optoelectronics, photovoltaic devices, and energy storage materials. The fabrication of wood-polymer hybrids preliminary involves the acquisition of delignified wood templates. In this framework, the potentiality of species diffused in the Mediterranean area is nearly unexplored. For such purpose, four hardwoods (Beech, European Hop Hornbeam, Turkey Oak and Paulownia) and one softwood (Corsican Pine) have been selected on the basis of their anatomical features, density, and potential exploitation of natural resources. The goal is to evaluate and compare the properties of delignified woods derived from the selected species for the fabrication of wood-polymer hybrids, including transparent wood products. Wood samples of different cut (longitudinal or transversal) and thickness (1 mm or 3 mm) were soaked in an alkaline sulfite solution and mildly bleached in hydrogen peroxide. Dry mass loss was determined in different experimental conditions. Macro- and microstructure of delignified woods have been investigated by optical microscopy, scanning electron microscopy, infrared spectroscopy and X-ray diffraction analysis. Thermal degradation profiles were acquired by thermogravimetry, the total transmittance measured in the UV–Vis range and mechanical properties evaluated by tensile tests. The dry mass loss ranged within 26–52%. Delignified hardwoods showed enhanced optical transmittance especially Paulownia (+ 80%) and Turkey Oak (+ 140%), characterized by large vessels and thin cell walls, while the macro- and mesostructure along with tensile properties were preserved. These cellulose-rich wood templates deserve to be further considered for the fabrication of wood-polymer hybrids and particularly transparent wood products. [ABSTRACT FROM AUTHOR]

This investigation aimed to assess the responsiveness of fourteen Moroccan bread wheat varieties to yellow rust induced by Puccinia striiformis tritici (Pst) in comparison with a susceptible variety 'Amal' through natural inoculation in the field, employing a Randomized Complete Block Design (RCBD). A comprehensive evaluation, encompassing 20 variables related to epidemiological, phenological, morphological, and physicochemical parameters, was conducted. In elucidating the role of the leaf in wheat resistance to stripe rust, the mineral and organic composition was scrutinized using sophisticated molecular detection techniques--Fourier Transform Infrared Spectroscopy (FTIR) and Atomic Absorption Spectroscopy (AAS). These two methodologies, recognized for their efficacy, facilitated the measurement of varying concentrations of lipids and carboxylic esters in the epicuticular wax on the adaxial flag leaf. Additionally, the quantity of essential minerals was determined. The outcomes revealed distinct responses among bread wheat varieties to stripe rust, with 'Faiza', 'Bandera', and 'Resulton' demonstrating heightened resistance, manifesting severity values below 15%. Conversely, 'Amal' exhibited the lowest level of resistance. Furthermore, lipid concentration reached its pinnacle in 'Faiza', 'Bandera' and 'Resulton' while 'Amal' displayed the lowest lipid levels. Severity exhibited a very weak correlation with Zn, weak correlations with Cu, and moderate correlations with Ca and K (p<0.05). This study provides valuable insights guiding future research endeavours aimed at enhancing the genetic traits of these elite cultivars for integration into Morocco's cereals program. [ABSTRACT FROM AUTHOR]

This investigation aimed to assess the responsiveness of fourteen Moroccan bread wheat varieties to yellow rust induced by Puccinia striiformis tritici (Pst) in comparison with a susceptible variety ‘Amal’ through natural inoculation in the field, employing a Randomized Complete Block Design (RCBD). A comprehensive evaluation, encompassing 20 variables related to epidemiological, phenological, morphological, and physicochemical parameters, was conducted. In elucidating the role of the leaf in wheat resistance to stripe rust, the mineral and organic composition was scrutinized using sophisticated molecular detection techniques—Fourier Transform Infrared Spectroscopy (FTIR) and Atomic Absorption Spectroscopy (AAS). These two methodologies, recognized for their efficacy, facilitated the measurement of varying concentrations of lipids and carboxylic esters in the epicuticular wax on the adaxial flag leaf. Additionally, the quantity of essential minerals was determined. The outcomes revealed distinct responses among bread wheat varieties to stripe rust, with ‘Faiza’, ‘Bandera’, and ‘Resulton’ demonstrating heightened resistance, manifesting severity values below 15%. Conversely, ‘Amal’ exhibited the lowest level of resistance. Furthermore, lipid concentration reached its pinnacle in ‘Faiza’, ‘Bandera’ and ‘Resulton’ while ‘Amal’ displayed the lowest lipid levels. Severity exhibited a very weak correlation with Zn, weak correlations with Cu, and moderate correlations with Ca and K (p

Background: Specifically designed peptide mimetics offer higher selectivity regarding their toxicity to mammalian cells. In addition to the α-helix conformation, the specific activity is related to the peptide's ability to penetrate the cell membrane. The alterations in lipid membrane properties were addressed in the presence of the peptide KLAKLAK-NH2 and analogs containing β-alanine, strengthening the antibacterial activity and/or naphtalimide with proven anticancer properties. Methods: The molecular interactions of the peptide mimetics with POPC bilayers were studied using FTIR-ATR spectroscopy. The thermal shape fluctuation analysis of quasispherical unilamellar vesicles was applied to probe the membrane bending elasticity. The impedance characteristics of bilayer lipid membranes were measured using fast Fourier-transform electrochemical impedance spectroscopy. Results: A lateral peptide association with the membrane is reported for β-alanine-containing peptides. The most pronounced membrane softening is found for the NphtG-KLβAKLβAK-NH2 analog containing both active groups that corroborate with the indications for 1,8-naphthalimide penetration in the lipid hydrophobic area obtained from the FTIR-ATR spectra analysis. The β-alanine substitution induces strong membrane-rigidifying properties even at very low concentrations of both β-alanine-containing peptides. Conclusions: The reported results are expected to advance the progress in tailoring the pharmacokinetic properties of antimicrobial peptides with strengthened stability towards enzymatic degradation. The investigation of the nonspecific interactions of peptides with model lipid membranes is featured as a useful tool to assess the antitumor and antimicrobial potential of new peptide mimetics. [ABSTRACT FROM AUTHOR]

Proteins are abundant biomolecules found in human cells, as well as pathogenic bacteria and viruses. Some of them become pollutants when released into water. Adsorption is an advantageous method for separating proteins in aqueous media since proteins are already immobilized on solid surfaces. Adsorbents with surfaces rich in tannins are efficient due to their affinity for strong interactions with the various amino acids that make up proteins. This work aimed to develop an adsorbent for protein adsorption in aqueous medium using lignocellulosic materials modified from eucalyptus bark and vegetable tannins. A more efficient resin was prepared containing 10% eucalyptus bark fibers and 90% tannin mimosa by condensation with formaldehyde, and it was characterized by UV–Vis, FTIR-ATR spectroscopy and determinations of degree of swelling, bulk and bulk density and specific mass. For UV–Vis spectroscopy the percentage of condensed and hydrolysable tannins in the extracts of fibers of the dry husks of Eucalyptus Citriodora was estimated and it was also determined your soluble solids. The study of bovine serum albumin (BSA) adsorption was carried out in batch with quantification by UV–Vis spectroscopy. The most efficient prepared resin obtained 71.6 ± 2.78% removal in a solution of 260 mg L−1 of BSA working in a better pH range of the aqueous solution of BSA in its isoelectric point, ~ 5, 32 ± 0.02, under these conditions, the synthesized resin can reach a maximum BSA adsorption capacity of ~ 26.7 ± 0.29 mg g−1 in 7 min. The new synthesized resin presents good prospects for adsorption of proteins or species that in their structure have higher percentages of amino functional groups or amino acids with aliphatic, acidic and/or basic hydrophilic characteristics. [ABSTRACT FROM AUTHOR]

Background: Specifically designed peptide mimetics offer higher selectivity regarding their toxicity to mammalian cells. In addition to the α-helix conformation, the specific activity is related to the peptide’s ability to penetrate the cell membrane. The alterations in lipid membrane properties were addressed in the presence of the peptide KLAKLAK-NH2 and analogs containing β-alanine, strengthening the antibacterial activity and/or naphtalimide with proven anticancer properties. Methods: The molecular interactions of the peptide mimetics with POPC bilayers were studied using FTIR-ATR spectroscopy. The thermal shape fluctuation analysis of quasispherical unilamellar vesicles was applied to probe the membrane bending elasticity. The impedance characteristics of bilayer lipid membranes were measured using fast Fourier-transform electrochemical impedance spectroscopy. Results: A lateral peptide association with the membrane is reported for β-alanine-containing peptides. The most pronounced membrane softening is found for the NphtG-KLβAKLβAK-NH2 analog containing both active groups that corroborate with the indications for 1,8-naphthalimide penetration in the lipid hydrophobic area obtained from the FTIR-ATR spectra analysis. The β-alanine substitution induces strong membrane-rigidifying properties even at very low concentrations of both β-alanine-containing peptides. Conclusions: The reported results are expected to advance the progress in tailoring the pharmacokinetic properties of antimicrobial peptides with strengthened stability towards enzymatic degradation. The investigation of the nonspecific interactions of peptides with model lipid membranes is featured as a useful tool to assess the antitumor and antimicrobial potential of new peptide mimetics.

The nanocomposites based on polyurethane matrix and multicomponent polymer matrices consisting of polyurethane and poly(hydroxypropyl methacrylate) with different contents of the last, and 1,2-propanediolisobutyl polyhedral oligomeric silsesquioxane (1,2-propanediolisobutyl-POSS), which was used as a functionalized nanofiller, were synthesized. The influence of the content of 1,2-propanediolisobutyl-POSS on intermolecular interactions and structural features of the nanocomposites was investigated by the method of IR-spectroscopy with Fourier transformation and attenuated total reflection (FTIR-ATR). The study of thermal curing of the model system, which consists of the adduct of trimethylolpropane with toluene diisocyanate and 1,2-propanediolisobutyl-POSS, made it possible to conclude that 1,2-propanediolisobutyl-POSS participates in the reaction of urethane formation using of one of the terminal hydroxyl groups, and it is incorporated into the polymer chain between cross-linking of polyurethane networks. The investigation of multicomponent polymer matrices by FTIR-ATR spectroscopy was done and was shown that photopolymerization of second polymer poly(hydroxypropyl methacrylate) in the matrix of polyurethane was completed by the opening of a double bond and the formation of a linear polymer in the composition of semi-IPN. Studies of nanocomposites based on multicomponent polymer matrices consisting of polyurethane and poly(hydroxypropyl methacrylate) with 15 and 30 % of the last by FTIR-ATR spectroscopy demonstrated the presence of POSS in the nanocomposites and the influence of POSS content on the structure of the studied systems and on the degree of phase separation. The POSS is «embedded» into the polymer chain between cross-linking of the polyurethane networks, with the additional formation of a complex system of intermolecular hydrogen bonds between the carboxyl and amine components of urethane groups in the nanocomposites. [ABSTRACT FROM AUTHOR]

This study aimed to ferment wheat grain by optimised bacteria, yeast and fungal fermentations. Crude protein, tannin, phytic acid and lactic acid contents of samples taken at 24 h intervals determined by chemical methods were compared with those of infrared (IR) spectro-chemometry. Secondary protein components were further quantified with IR spectra deconvolution method. The results indicated that some fermentations increased crude protein of wheat, whilst its tannin and phytic acid degraded in all fermentations. Wheat enriched with lactic acid content in all fermentations. FT-IR spectroscopic method accurately (99.99% of recovery) and precisely (regression coefficient of prediction R2 = 0.999, P

The question addressed in this paper is whether cotton textiles mercerized with liquid ammonia (L-NH3) can be distinguished from NaOH mercerized cotton textiles with FTIR-ATR spectroscopy. In collaboration with a process-house, cotton textiles were treated with L-NH3, NaOH, neither or both. The treatment conditions were set to mimic commercial-scale operations. The samples were then analyzed with FTIR-ATR spectroscopy, and for comparison, also with powder X-ray diffraction. The analyses were aimed at detecting changes in the cellulose crystal lattice structure that result from the two mercerization processes. The measured spectra and diffractograms were evaluated both visually and with Principal Component Analysis (PCA), and the results show that with FTIR-ATR spectroscopy it was possible to differentiate between the untreated, L-NH3 mercerized and NaOH mercerized textiles, whereas with X-ray diffraction it was difficult to detect differences between the untreated and treated samples. The better performance of FTIR-ATR spectroscopy is attributed to the method being more sensitive to changes on sample surfaces, whereas X-ray diffraction results are more representative of the sample bulk. The samples were treated under conditions mimicking commercial-scale operations, which are optimized to maximize treatment speed. Hence, the mercerization induced changes are likely to be limited to sample surfaces and hence detectable with FTIR-ATR spectroscopy but not with X-ray diffraction. It is reported that Sum Frequency Generation Vibrational Spectroscopy, another surface-limited analytical method, may also be employed for detection of mercerization type, but FTIR-ATR spectroscopy has the advantages of ease of operation and the devices are less expensive. [ABSTRACT FROM AUTHOR]

The genus Trichoderma is composed of important biocontrol agents. The morphological and molecular characterisation of fungi is demanding and time-consuming. The use of Fourier transform infrared spectroscopy (FTIR) in the medium infrared range (MIR) can be a simple and fast technique to study fungi. The objectives of this study were to explore and characterise the spectrum signature of Trichoderma strains using FTIR in the MIR (650–4000 cm−1) with attenuated total reflectance (ATR). Therefore we investigated the spectrum regions for characterisation, the interference of prepared sample solutions for their resolution and the ability to differentiate Trichoderma spp. Results from this method were compared with molecular analysis. The spectra of eight Trichoderma spp. were assessed. The samples were prepared using ultrapure water, 50% alcohol, and 99.5% alcohol. Initially, the whole spectrum of each isolate was considered; then, three potential regions were isolated: 650–3000 cm−1 (region I), 3000–4000 cm−1 (region II), and 800–1800 cm−1 (region III). In addition, molecular analysis for genetic diversity study using the internal transcribed spacer (ITS) region was performed. FTIR spectroscopy resolution was improved when 50% alcohol solution was used to prepare the samples. Region III presented the best clustering. Genetic diversity was congruent with FTIR spectroscopy. FTIR-ATR in the MIR range 800–1800 cm−1 with 50% alcohol samples enabled the characterisation and differentiation of Trichoderma spp. according to genetic diversity. This technique can be a fast and efficient method to characterise and differentiate Trichoderma samples. [ABSTRACT FROM AUTHOR]

Objective To evaluate the early stages of the setting process of chemically activated restorative glass-ionomer cements (GICs). Material and methods Five GICs were evaluated (n = 5): Equia Forte (GC), Equia Forte HT (GC), Ketac Universal (3M ESPE), Maxxion R (FGM) and Riva Self Cure (SDI) by Thermography, Fourier Transform Infrared Attenuated Total Reflectance Spectroscopy (FTIR-ATR) and Gillmore needle indentation mechanical testing. The FTIR-ATR spectra showed the formation of metal carboxylates within the cements and enabled the stabilization time (ST) to be determined and the thermographic camera measured the temperature field images in the sample. Data were statistically analyzed by ANOVA and Tukey–Kramer (α = 5%). Results The Gillmore needle test showed that the order of hardening was opposite to the order of ST values determined by FTIR. The results with the thermographic camera showed two stages of temperature variation, which coincided with the evolution of specific infrared bands. The exception was Maxxion R, which showed only a single step change in temperature. Conclusion The early stages of the GIC setting reaction show temperature changes, both endothermic and exothermic, at specific times, confirming the occurrence of individual chemical reactions. The early setting involves reactions other than carboxylate formation. Significance: This study gives further detail of the early stages of the setting of GICs, and past research regarding the setting reaction of GIC.

Hemolymph is a liquid of the open circulatory system of the honey bee (Apis mellifera L.) which represents a functional equivalent of vertebrate blood and lymph. The aim of this study was to determine the overall biochemical composition of honey bee hemolymph based on chemical characterization using Fourier transform infrared (FTIR) spectroscopy. Individual hemolymph samples of two age groups of workers (newly emerged bees-1 day old; foragers-42 days old) were collected by extraction from the thorax, and analysed by FTIR-ATR (Attentuated Total Reflectance) recording technique. The results have revealed a unique IR chemical fingerprint of honey bee hemolymph. Characteristic age-related spectral features indicating compositional variations between newly emerged bees and foragers were observed.

Three types of honeys viz. Robinia pseudoacacia (RSA), Plectranthus rugosus (PR) and multifloral honey (MF) from Kashmir Himalayas of India were characterized on the basis of physicochemical, antioxidant and FTIR-ATR spectroscopic features. The physicochemical parameters indicated that ash content, electrical conductivity, redness (a*) and yellowness (b*) were higher in MF honey, moisture content, Hydroxymethylfurfural (HMF) and lightness (L*) in PR honey and Water activity (aw) and proline content in RSA honey (P ≤ 0.05). Significantly higher values of total sugar, total reducing sugar and sucrose content was observed in MF honey (P ≤ 0.05). The total phenolic content (TPC), total flavonoids, ferric reducing antioxidant power and 1, 1-diphenyl-2-picrylhydrazy-IC50 (DPPH- IC50) free radical scavenging activity showed that MF honey had significantly higher antioxidant activity (P ≤ 0.05). ATR-FTIR analysis demonstrated that the absence of peaks at broad band around 1653.454–1637.656 cm−1 in MF honey, 1185.989–1153.072 cm−1 and 918.570–916.544 cm−1 wavenumbers in PR honey thus clearly discriminating different types of honeys. The results revealed that physico-chemical, antioxidant and spectroscopic characteristics of honey types vary with geographic origin and their floral sources and MF honey have a high therapeutic potential. [ABSTRACT FROM AUTHOR]

Changes in land use are very important factors affecting soil quality and especially the concentration and stock of soil organic carbon (SOC) and total nitrogen (TN). Very little is known about changes in spectroscopic properties of SOM after conversion of forestland to cropland. Therefore, the main aim of this study was to determine impact of agriculture on the concentration and stock of SOC and TN as well as spectroscopic properties of SOM in the topsoil horizons of Retisols in the Carpathian Foothills in southern Poland. Topsoil Ap horizons of arable soils are characterized by a significantly lower concentration of SOC and TN in comparison with topsoil Oi and Ah horizons of forestland soils. Topsoil Ap horizons feature higher SOC and TN stocks than topsoil Oi and Ah horizons. Significantly higher concentrations of SOC and TN in Oi horizons in comparison with Ah and Ap horizons are responsible for significantly higher mean absorbance values of all FTIR-ATR absorption bands originating from SOM in Oi horizons versus Ah and Ap horizons. Significantly higher concentrations of SOC and TN in Ah horizons of forestland soils versus those in Ap horizons of arable soils do not significantly affect mean absorbance values of FTIR-ATR bands. [ABSTRACT FROM AUTHOR]

Brazilian law forbids the addition of cheese whey in milk. However, adulteration with cheese whey is one of the most applied fraud due to its low cost. The detection of this fraud is the quantification of Caseinomacropeptide (CMP). The CMP is a constituent of the whey that can be used as adulteration marker. Thus, an analytical method capable of identifying CMP by Fourier Transform Infrared Spectra (FTIR) was developed using chemometrics methods. Firstly, we attempted to develop an exploratory analysis model by Hierarchical Grouping Analysis (HCA) and Principal Component Analysis (PCA) that indicated similarity between samples of raw milk and semi-skimmed milk. Moreover, in the PCA scores, it was possible to observe a tendency of separation between samples with different concentrations of CMP. Afterwards, multivariate regression models were used for Partial Least Squares (PLS), Partial Least Square with Interval Synergism (siPLS) and Supporting Machines with Least Squares (LS-SVM) to quantify the adulteration in different types of milk by Cheese serum through the CMP. All the models were then compared to each other and the results of the official method with Liquid Chromatography Tandem mass spectrometry (LCMS/MS) analysis used by the Ministry of Livestock and Supply (MAPA). The model LS-SVM, employing the full spectrum, obtained the best result compared to the other models (PLS and siPLS) to quantify the CMP in the milk samples.

Thyroid hormones like Tri iodothyronine (T3) Thyroxine (T4) and Thyroid Stimulating Hormones (TSH) are important regulators for differentiation, growth and metabolism of virtually all tissues. Great efforts are ongoing in understanding and management of thyroids, the disease and disease related complications are increasingly unabated. It is known that thyroid hormones have an effect on tissue damage The objective of this study was to determine hypothyroidism causes cellular damage in the different tissues. In the present investigation an attempt is made to study the histological changes in the heart, lung, thyroid glands and muscle caused by carbimazole an anti thyroid drug or hypothyroidism. To achieve this experiments were conducted on male wistar rat treated with carbamizole to induce hypothyroid which causes cellular disturbances in different tissue/organs. FTIR-ATR spectral and Histological studies in different organs were concentrated. The spectral peaks in the region of 4000-450 cm-1 were chosen to characterize structural and morphological nature and tissues like myocardium, muscle, liver, lung, intestine and kidney etc., of control and experimental rats for clinical diagnosis and disease management. Based on the spectrum obtained it was possible to assign bands to analyze triglycerides and cholesterol esters, proteins, phosphate macromolecules phospholipids, phosphorylated proteins, glycogen, lactate etc. The chemical variation on spectrum in tissues of control and experimental animals were evaluated for comparison The comparison of spectral information gathered from FTIR spectra of the tissues sections can be successfully employed in the investigations of biochemical variation in animal tissues. The effect of drug induced hypothyroid also explained the changes in chemical and histological variations on different tissues. Moreover, it can be used in the clinical diagnostic studies to correlate the overall biochemical status of the tissue with the pathological changes. The significance of FTIRATR in disease diagnosis particularly hypothyroidism discussed in detail. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the early stages of the setting process of chemically activated restorative glass-ionomer cements (GICs). Material and methods: Five GICs were evaluated (n = 5): Equia Forte (GC), Equia Forte HT (GC), Ketac Universal (3M ESPE), Maxxion R (FGM) and Riva Self Cure (SDI) by Thermography, Fourier Transform Infrared Attenuated Total Reflectance Spectroscopy (FTIR-ATR) and Gillmore needle indentation mechanical testing. The FTIR-ATR spectra showed the formation of metal carboxylates within the cements and enabled the stabilization time (ST) to be determined and the thermographic camera measured the temperature field images in the sample. Data were statistically analyzed by ANOVA and Tukey-Kramer (a = 5%). Results: The Gillmore needle test showed that the order of hardening was opposite to the order of ST values determined by FTIR. The results with the thermographic camera showed two stages of temperature variation, which coincided with the evolution of specific infrared bands. The exception was Maxxion R, which showed only a single step change in temperature. Conclusion: The early stages of the GIC setting reaction show temperature changes, both endothermic and exothermic, at specific times, confirming the occurrence of individual chemical reactions. The early setting involves reactions other than carboxylate formation. Conclusion: Significance: This study gives further detail of the early stages of the setting of GICs, and past research regarding the setting reaction of GIC. [ABSTRACT FROM AUTHOR]

This study aimed to ferment wheat grain by optimised bacteria, yeast and fungal fermentations. Crude protein, tannin, phytic acid and lactic acid contents of samples taken at 24 h intervals determined by chemical methods were compared with those of infrared (IR) spectro-chemometry. Secondary protein components were further quantified with IR spectra deconvolution method. The results indicated that some fermentations increased crude protein of wheat, whilst its tannin and phytic acid degraded in all fermentations. Wheat enriched with lactic acid content in all fermentations. FT-IR spectroscopic method accurately (99.99% of recovery) and precisely (regression coefficient of prediction R2 = 0.999, P <0.0001) predicted these nutrient contents. Fermentation positively caused a re-organised secondary protein conformation; the percentages of ß-sheet and α-helix increased by 68 and 140%, respectively, whereas the random coil decreased by 63%. FT-IR spectrometry combined with suitable chemometric tools provided a fast and robust monitoring of chemical and structural changes during microbial fermentation. [ABSTRACT FROM AUTHOR]

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Asian soybean rust, Phakopsora pachyrhizi, is the most devastating disease in the soybean crop. Despite efforts to control the disease, such as a soybean-free period and cultivar resistance, outbreaks have been increasing in Brazil, with losses reaching 80%. Chemical control is the main strategy adopted by South American farmers to control the disease. Fungicide application is recommended before the occurrence of symptoms; monitoring for spores can improve decision-making and treatment applications. The objective of this study was to identify a spectral signature for the fungus P. pachyrhizi and quantify the number of urediniospores in a sample of water using the Fourier Transform Infrared spectroscopy technique in the MIR range, 650 cm−1 to 4000 cm−1, with the attenuated total reflectance (ATR) accessory. In FTIR spectroscopy, the samples are irradiated by infrared light resulting in absorption of energy by molecular vibrations. Fungus samples were collected in 48 Brazilian soybean growth regions. A total of 130 samples were assessed. The characterization of fungi samples was conducted using Infrared Spectroscopy from 1000 cm−1 to 1560 cm−1. The spectral signature of P. pachyrhizi was between 1500 cm−1 to 1550 cm−1. The quantification showed high values for the calibration coefficients (R2 = 0.9478), cross validation (R2 = 0.9330) and prediction (R2 = 0.9236), which demonstrates the accuracy for estimation of the number of urediniospores. The FTIR-ATR spectroscopy enables the characterization and quantification of P. pachyrhizi urediniospores in water samples, creating a more efficient way to monitor spore dispersal and management of this disease. [ABSTRACT FROM AUTHOR]

Although beeswax adulteration represents one of the main beeswax quality issues, there are still no internationally standardised analytical methods for routine quality control. The objective of this study was to establish an analytical procedure suitable for routine detection of beeswax adulteration using FTIR-ATR spectroscopy. For the purpose of this study, reference IR spectra of virgin beeswax, paraffin, and their mixtures containing different proportions of paraffin (5 - 95%), were obtained. Mixtures were used for the establishment of calibration curves. To determine the prediction strength of IR spectral data for the share of paraffin in mixtures, the Partial Least Squares Regression method was used. The same procedure was conducted on beeswax-beef tallow mixtures. The model was validated using comb foundation samples of an unknown chemical background which had been collected from the international market (n = 56). Selected physico-chemical parameters were determined for comparison purposes. Results revealed a strong predictive power (R2 = 0.999) of IR spectra for the paraffin and beef tallow share in beeswax. The results also revealed that the majority of the analysed samples (89%) were adulterated with paraffin; only 6 out of 56 (11%) samples were identified as virgin beeswax, 28% of the samples exhibited a higher level of paraffin adulteration (>46% of paraffin), while the majority of the analysed samples (50%) were found to be adulterated with 5 - 20% of paraffin. These results indicate an urgent need for routine beeswax authenticity control. In this study, we demonstrated that the analytical approach defining the standard curves for particular adulteration levels in beeswax, based on chemometric modelling of specific IR spectral region indicative for adulteration, enables reliable determination of the adulterant proportions in beeswax.

This work addresses the impact of fabrication conditions (curing procedure, moisture) on the properties of a two-part polyurethane system. While Part I treats the chemical, dielectric and mechanical properties during cure and storage in dry conditions , this second part focuses on these properties, along with the caloric glass transition, in moist conditions , with moisture being introduced at different times during and right after cure. It is shown that the presence of water during fabrication severely affects final properties (increased polymer mobility, reduced mechanical stiffness) by reacting with isocyanate (forming primary amines and urea) and thereby lowering crosslink density, even for seemingly uncritical humidity conditions. Other chemical side reactions involving moisture are also identified. Water furthermore accelerates polymer dynamics substantially. Overall, moisture during cure and storage is clearly identified as a cause for property variations of PU. [ABSTRACT FROM AUTHOR]

The differentiation of roots of agricultural species is desired for a deeper understanding of the belowground root interaction which helps to understand the complex interaction in intercropping and crop-weed systems. The roots can be reliably differentiated via Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR). In two replicated greenhouse experiments, six pea cultivars, five oat cultivars as well as seven maize cultivars and five barnyard grass proveniences (n = 10 plants/cultivar or provenience) were grown under controlled conditions. One root of each plant was harvested and five different root segments of each root were separated, dried and measured with FTIR-ATR spectroscopy. The results showed that, firstly, the root spectra of single pea and single oat cultivars as well as single maize and single barnyard grass cultivars/proveniences separated species-specific in cluster analyses. In the majority of cases the species separation was correct, but in a few cases, the spectra of the root tips had to be omitted to ensure the precise separation between the species. Therefore, species differentiation is possible regardless of the cultivar or provenience. Consequently, all tested cultivars of pea and oat spectra were analyzed together and separated within a cluster analysis according to their affiliated species. The same result was found in a cluster analysis with maize and barnyard grass spectra. Secondly, a cluster analysis with all species (pea, oat, maize and barnyard grass) was performed. The species split up species-specific and formed a dicotyledonous pea cluster and a monocotyledonous cluster subdivided in oat, maize and barnyard grass subclusters. Thirdly, cultivar or provenience differentiations within one species were possible in one of the two replicated experiments. But these separations were less resilient. [ABSTRACT FROM AUTHOR]

In recent years, there has been growing interest in verifying the floral origin of unifloral honeys, as a very interesting natural remedy. Fourier Infrared Spectroscopy (FTIR) is more and more frequently used in honey identification and their quality control. The aim of this study was to develop procedures allowing for authentication of rape ( Brassica ) honey by chemometrics and spectroscopy. The FTIR-ATR spectrum of rape pollen was used as a reference to determine the rape pollen content within the investigate rape honey samples. The higher percentage of rape pollen contained the rape honey, the more similarities were observed between the respective spectra of these two samples, while the spectra of other honey types differed significantly. Discriminant analysis demonstrated, that the absorbance values at 1540 cm −1 , 1650 cm −1 , 1740 cm −1 were the parameters unambiguously identifying rape honey. According to the Classification Tree Analysis, peaks at 1000–1200 cm −1 , 1650 cm −1 , 1740 cm −1 wavenumbers were significant with threshold absorbance values 0.70787, 0.11467 and 0.3605, respectively. The FTIR-ATR spectroscopy technique supplemented by chemometrics allow for quick identification of rape honey. [ABSTRACT FROM AUTHOR]

A FTIR-ATR coupled to chemometry method was first-ever tested in monitoring the effects of a range of bacterial, yeast and fungal fermentations on nutrient and chemical composition of barley. Chemically analysed contents of samples taken at 24 h intervals were predicted by a partial least square regression (PLSR) model. Moreover, secondary protein components (SPC) of barley protein were measured by a Gaussian curve fitting of amid I spectral region. The results showed that crude ash content of barley increased significantly in Aspergillus oryzae + Bacillus subtilis fermentation and crude protein content in Lactobacillus salivarius fermentation. Organic acid content (especially lactic acid) increased in all fermentations of barley with bacteria, fungal and yeast, while crude fiber and anti-nutritional contents such as phytic acid and tannin decreased. On the other hand, PLSR model based on second derivate spectral data has highly acceptable performance characteristics in predicting protein, ash, fibre, lipid and starch: low RMSEV (root mean squared error of calibration) of 0.0003–1.24 with r2 = 0.999 and RMSECV (root mean squared error of cross validation) of 0.004–1.88 with R2 = 0.988, high recovery rate (closeness to analysed value) of almost 100.0, high precision VC p % (variance coefficient of prediction) of less than 5.0% and RPD (relative performance determinant) values of over 2.0. Barley protein was seen to be subjected to a useful hydrolysis, degradation and aggregation of microbial fermentation, as measured in SPC percentages. The decreased percentages of β-sheet, α-helix components and random coil associated with increased percentage of β-turn component is more likely an indication of improved protein quality. We recommended the model employed herein is robust and can replace the analytical methods of wet chemistry in feed analysis in nutritional studies and in routine analysis by the industry to monitor in line fermentation processes. • Microbial fermentation enriched barley grains nutrient and reduced anti-nutrients. • ATR-FTIR provided a fast robust measurement of nutritional composition. • Secondary components of barley protein can be quantified by FTIR combined chemometry. [ABSTRACT FROM AUTHOR]

Four simple, accurate, sensitive and economic Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopic (ATR-FTIR) methods have been developed for the quantitative estimation of some non-steroidal anti-inflammatory drugs. The first method involves the determination of Etodolac by direct measurement of the absorbance at 1716 cm − 1 . In the second method, the second derivative of the IR spectra of Tolfenamic acid and its reported degradation product (2-chlorobenzoic acid) was used and the amplitudes were measured at 1084.27 cm − 1 and 1056.02 cm − 1 for Tolfenamic acid and 2-chlorobenzoic acid, respectively. The third method used the first derivative of the IR spectra of Bumadizone and its reported degradation product, N , N -diphenylhydrazine and the amplitudes were measured at 2874.98 cm − 1 and 2160.32 cm − 1 for Bumadizone and N , N -diphenylhydrazine, respectively. The fourth method depends on measuring the amplitude of Diacerein at 1059.18 cm − 1 and of rhein, its reported degradation product, at 1079.32 cm − 1 in their first derivative spectra. The four methods were successfully applied on the pharmaceutical formulations by extracting the active constituent in chloroform and the extract was directly measured in liquid phase mode using a specific cell. Moreover, validation of these methods was carried out following International Conference of Harmonisation (ICH) guidelines. [ABSTRACT FROM AUTHOR]

The ability of Captisol ® (sulphobutylether-β-cyclodextrin, SBE-β-CD), to form inclusion complexes, both in solution and in the solid state, has been tested in order to improve some unfavorable chemical-physical characteristics, such as poor solubility in water, of a bioflavonoid, Coumestrol (Coum), well known for its anti-oxidant, anti-inflammatory, anti-fungal and anti-viral activity. In pure water, a phase-solubility study was carried out to evaluate the enhancement of the solubility of Coum and, therefore, the occurred complexation with the macrocycle. The stoichiometry and the stability constant of the SBE-β-CD/Coum complex were calculated with the phase solubility method and through the Job's plot. After that, the solid SBE-β-CD/Coum complex was prepared utilizing a kneading method. The spectral changes induced by complexation on characteristic vibrational band of Coum were complementary investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR) and Raman spectroscopy, putting into evidence the guest chemical groups involved in the “host-guest” interactions responsible of the formation and stabilization of the complex. Particular attention was paid to the C O and O H stretching vibrations, whose temperature-evolution respectively furnished the enthalpy changes associated to the binding of host and guest in solid phase and to the reorganization of the hydrogen bond scheme upon complexation. From the whole set of results, an inclusion geometry is also proposed. [ABSTRACT FROM AUTHOR]

In the present study, silver nanoparticles (AgNPs) were synthesised by adding 1 mM Ag nitrate solution to different concentrations (1%, 2.5%, 5%) of branch extracts of Eurycoma longifolia, a well known medicinal plant in South–East Asian countries. Characterisation of AgNPs was carried out using techniques such as ultraviolet–visible spectrophotometry, X‐ray diffractrometry, Fourier transform infrared–attenuated total reflection spectroscopy (FTIR–ATR), scanning electron microscopy. XRD analysis revealed face centre cubic structure of AgNPs and FTIR–ATR showed that primary and secondary amide groups in combination with the protein molecules present in the branch extract were responsible for the reduction and stabilisation of AgNPs. Furthermore, antioxidant [2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐Azino‐bis(3‐ethylbenzthiazoline‐6‐sulphonic acid)], antimicrobial and anticancer activities of AgNPs were investigated. The highest bactericidal activity of these biogenic AgNPs was found against Escherichia coli with zone inhibition of 11 mm. AgNPs exhibited significant anticancer activity against human glioma cells (DBTRG and U87) and human breast adenocarcinoma cells (MCF‐7 and MDA‐MB‐231) with IC50 values of 33, 42, 60 and 38 µg/ml. [ABSTRACT FROM AUTHOR]

Due to their chemical and morphological versatility, polyurethanes may be susceptible to fabrication conditions (curing procedure, moisture). Industry reports ‘maturation’ phenomena, i.e. unstable mechanical properties of PU elastomers and PU based adhesive joints right after fabrication. This paper elucidates the impact of fabrication conditions and possible causes of maturation. Chemical and physical bulk properties of a crosslinking two-part PU are monitored during and after cure in dry atmosphere (at room temperature followed by a post-cure). The influence of curing procedure is revealed by processes characteristic of the post-cure, i.e. chemical side reactions (allophanate, carbodiimide) and a new dielectric relaxation. Tensile tests demonstrate the practical relevance of the findings (mechanical modulus). Properties of the fully crosslinked, dryly stored PU are stable during a three-week observation, indicating that maturation is preventable by complete cure and dry conditions. In contrast, chemical crosslinking after an insufficient cure likely causes maturation phenomena. [ABSTRACT FROM AUTHOR]

The performance of the widely used analytical techniques in monitoring the changes from light on edible oils was compared. Flax, soybean, peanut, sunflower, olive and corn oils were subdued to forced irradiation and analyzed by IR spectroscopy, UV-visible spectroscopy and HPLC. The stressing test was executed in agreement with international rules and the samples were analyzed at time intervals up to 540 min. The results recorded by the spectrometric techniques were completely different. All IR spectra recorded along the test were superimposable, indicating full stability of all oils even after multivariate elaboration by principal component analysis. In contrast, UV spectra showed a constant variation, stating a clear photolability. HPLC-DAD determination of the main fatty acids confirmed the photodegradation of the samples, showing a clear decrease in their concentration. This study provides information on the photostability of various edible oils, which could be useful for their proper storage. Moreover, the results clearly indicate that the IR spectrometry is not appropriate to evaluate the photostability of the oils. On the contrary, UV spectrometry is able to provide a rapid evaluation of the degradation degree and HPLC an effective assessment on the degradation of some important components such as the unsaturated fatty acids. [ABSTRACT FROM AUTHOR]

In marine ecosystems, microalgae are an important component as they transform large quantities of inorganic compounds into biomass and thereby impact environmental chemistry. Of particular relevance is phytoplankton's sequestration of atmospheric CO 2 , a greenhouse gas, and nitrate, one cause of harmful algae blooms. On the other hand, microalgae sensitively respond to changes in their chemical environment, which initiates an adaptation of their chemical composition. Analytical methodologies were developed in this study that utilize microalgae's adaptation as a novel approach for in-situ environmental monitoring. Longterm applications of these novel methods are investigations of environmental impacts on phytoplankton's sequestration performance and their nutritional value to higher organisms feeding on them. In order to analyze the chemical composition of live microalgae cells ( Nannochloropsis oculata ), FTIR-ATR spectroscopy has been employed. From time series of IR spectra, the formation of bio-sediment can be monitored and it has been shown that the nutrient availability has a small but observable impact. Since this bio-sediment formation is governed by several biological parameters of the cells such as growth rate, size, buoyancy, number of cells, etc., this enables studies of chemical environment's impact on biomass formation and the cells' physical parameters. Moreover, the spectroscopic signature of these microalgae has been determined from cultures grown under 25 different CO 2 and NO 3 − mixtures (200 ppm-600 ppm CO 2 , 0.35 mM-0.75 mM NO 3 − ). A novel, nonlinear modeling methodology coined ‘Predictor Surfaces’ is being presented by means of which the nonlinear responses of the cells to their chemical environment could reliably be described. This approach has been utilized to measure the CO 2 concentration in the atmosphere over the phytoplankton culture as well as the nitrate concentration dissolved in their growing environment. The achieved precision of concentration predictions were a few percent of the measurement range. Moreover, the Predictor Surface itself allows for a chemical interpretation of the cells' response to a shift in their chemical environment. This will open new approaches to study the link between concentration levels in an ecosystem and the biological consequences for this ecosystem. [ABSTRACT FROM AUTHOR]

A previous study of the Cypriot pottery collection housed in the Ian Potter Museum of Art at the University of Melbourne found approximately two-thirds of adhesive repairs are primarily composed of cellulose nitrate (CN). This is of concern as CN has a limited lifespan (6-20 years), which has implications for the strategic management of the collection. To gain a greater understanding of the prevalence of CN based adhesive repairs in the archaeological context, the original FTIR-ATR spectroscopic survey was extended to incorporate the University's Middle Eastern archaeological pottery collection. Micro-samples were removed from artefacts using acetone swabs. Analysis of adhesive FTIR spectra identified CN to be present not only as the primary polymer in approximately one-tenth of repairs, but also as a secondary polymer in poly(vinyl acetate) (PVAc) and acrylic adhesive formulations, observed as a weak peak at ~1656 cm. CN's secondary presence in PVAc adhesive formulations is demonstrated using principal component analysis (PCA) and the diphenylamine spot test for CN. Re-analysis of adhesive IR spectra from the Cypriot pottery collection found CN to be present as a secondary polymer in this collection as well. It is concluded a combined methodology of collecting and identifying FTIR-ATR spectra of adhesive repairs from archaeological pottery collections followed by PCA analysis bring to light adhesive formulations which can inform the management of pottery collections. [ABSTRACT FROM AUTHOR]

Acetic acid treatment for an accurate differentiation between ancient and recent human bones was assessed using Raman and FTIR-ATR spectroscopies. Each set of skeletal samples was analysed by these techniques, prior and after chemical washing, in order to determine the variations in bone´s chemical composition and crystallinity. Bone samples were collected from several independent sources: recent bones burned under controlled experimental conditions or cremated, and archaeological (XVII century and Iron Age). The effect of acetic acid, expected to impact mostly on carbonates, was clearly evidenced in the spectra of all samples, particularly in FTIR-ATR, mainly through the bands typical of A- and B-carbonates. Furthermore, as seen for crematoria and archaeological samples, acetic acid was found to remove contaminants such as calcium hydroxide. Overall, acetic acid treatment can be an effective method for removing carbonates (exogenous but possibly also endogenous) and external contaminants from bone. However, these effects are dependent on the skeletal conditions (e.g. post-mortem interval and burning settings). In addition, this chemical washing was shown to be insufficient for an unequivocal discrimination between recent and archaeological skeletal remains. Based on the measured IR indexes, only cremated bones could be clearly distinguished. [Display omitted] • Optimal experimental conditions were obtained with acetic acid 0.1 M for 4 h. • Acetic acid treatment removed carbonates and calcium oxides from bones. • C/C index distinguished gas-fuelled crematorium samples from other samples. [ABSTRACT FROM AUTHOR]

Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy was combined with multivariate data analysis to investigate the chemical changes in wood during particle- and medium density fibreboard (MDF) production of grand fir (Abies grandis [Douglas ex D. Don] Lindl.) and European beech (Fagus sylvatica L.). The mechanical and technological properties of the novel particle- and fibreboards from beech or grand fir wood were similar to those of conventional panels from pine and spruce. This indicates that these timbers can be used as resources for wood-based panel production. Principal component analysis of FTIR spectra differentiated wood, fibres, particles, MDF, and particleboards of both species in the whole production process. Modifications in the spectra of fibres and particles suggested that cellulose properties of wood were changed during mechanical pulping. Wet chemical analysis confirmed that the furfural content was lower in fibres and higher MDF boards than in wood. Different binders and hydrophobic additives were clearly traceable and discernable in wood composites. Samples from the same production step were clustered together, indicating high homogeneity of the raw materials, and intermediate and final products, respectively. This suggests that FTIR spectroscopy in combination with cluster analysis is a useful tool to assess product quality and can be further developed to control and optimize production processes for innovative wood-based panels.

Fourier transform infrared spectroscopy based on attenuated total reflectance sampling technique, combined with multivariate analysis methods was used to monitor the adulteration of pure sunflower oil (SO) with thermally deteriorated oil (TDO). Contrary to published research, in this work, SO was thermally deteriorated in the absence of foodstuff. SO samples were exposed to temperatures between 125 and 225°C from 6 to 24 h. Quantification of adulteration of SO with TDO, based on principal components regression (PCR), partial least squares regression (PLS-R), and linear discriminant analysis (LDA) applied to mid-infrared spectra and to their first and second derivatives is reported for the first time. Infrared frequencies associated with the biochemical differences between TDO samples deteriorated in different conditions were investigated by principal component analysis (PCA). LDA was effective in the twofold classification presence/absence of TDO in adulterated SO (with 5% V/V of less of TDO). It provided 93.7% correct classification for the calibration set and 91.3% correct classification when cross-validated. A detection limit of 1% V/V of TDO in SO was determined. Investigation of an external set of samples allowed the evaluation of the predictability of the models. The regression coefficient (R2) for prediction was 0.95 and 0.96 and the RMSE was 2.1 and 1.9% V/V when using the PCR or PLS-R models, respectively, and the first derivative of spectra. To the best of our knowledge, no investigation of adulteration of SO with TDO based on PCR, PLS-R, and LDA has been reported so far.

Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy was used to examine the impact of hydrogen bonding on the reactive amine and hydroxyl groups of chitosan. Measurements were performed on powder and film samples hydrated under different conditions. To resolve the individual OH and NH bands that overlap in the region between 3000 and 3800 cm −1 , the spectra were deconvoluted using a Gaussian curve fitting method. By analyzing the changes recorded for each Gaussian component along the dehydration process of the films at different pH values, a band assignment was proposed. This assignment was then used to analyze the ATR-FTIR spectra of the chitosan/montmorillonite composites. The changes induced by the presence of the clay were ascribed to particular mechanisms of interaction that involve the active sites of the clay and the amino or hydroxyl groups of chitosan. The comparison between the FTIR and the XRD data, evidenced that these mechanisms are intimately controlled by the type of nanostructures that are formed depending on the clay content. [ABSTRACT FROM AUTHOR]

The purpose of the present study is to analyze the effect of the new nanofiller type graphene–gold nanoparticles on the surface structure and surface properties of some dental nanocomposites based on BisGMA/triethyleneglicol dimethacrylate matrix. Materials used in our study were three experimental nanocomposites, two of them based on graphene–gold nanoparticles as filler of different percent. As reference material, a commercial dental nanocomposite product named Herculite XRV Ultra was used. FTIR-ATR spectroscopy was used to determine the residual double bonds and the degree of conversion (DC) after 1 and 21 days of immersion in distilled water at 37 °C. The difference in DC between the experimental materials was statistically analyzed by one tail, paired Student’s t-Tests, using Graph Pod. Surface properties were evaluated through surface free energy using contact angle measurement while roughness and topography was assessed using Atomic Force Microscopy (AFM). To determine the amount of filler particles and thermal behavior of organic matrix, the nanocomposites were investigated by thermal analysis. According to the experimental results, the dental nanocomposites with highest percent in graphene–gold nanoparticles present a better value for the surface free energy. AFM investigations reveal differences in the term of roughness properties and suggest that in order to improve the surface properties is necessary to use a higher percent of graphene–gold nanoparticles as filler. The degradation process of major nanocomposites constituents is observed at temperatures between 240 and 620 °C. Entire results sustain this, but the future studies in order to evaluate the biological properties of the experimental nanocomposites will be made. [ABSTRACT FROM PUBLISHER]

The effect of a polyanionic variably substituted sulfobutyl ether-β-cyclodextrin (SBE-β-CyD), complexation on the UV absorption of genistein (Gen) and daidzein (Dai) was studied in pure water. A phase solubility study was performed, according to the method reported by Higuchi and Connors, to evaluate the changes of isoflavones in the complexation state and type-A solubility diagrams for both isoflavones were obtained suggesting that they form complexes with 1:1 molar ratio. These results were confirmed by Job's plot method. Complexation strongly increases the water solubility of isoflavones. The in vitro dissolution of isoflavones entrapped into SBE-β-CyD significantly surpassed that of the free isoflavones (over 90 % of the loaded Gen and Dai dissolved in 15 and 30 min, respectively). Finally, 1:1 molar ratio solid complexes were prepared by the kneading method and characterized in solid state by FTIR-ATR spectroscopy, with particular regard to O-H and C=O stretching vibrations, achieving structural information on the modifications induced by complexation on the H-bond scheme, also by applying band decomposition and curve-fit. [ABSTRACT FROM AUTHOR]

The membrane perturbing potency of the highly effective anti-multidrug resistance (MDR) pyrimidine analog of fluphenazine (FPh-prm), has been studied using attenuated total reflectance Fourier-transfer infrared spectroscopy (FTIR-ATR). The temperature- and FPh-prm-dose-dependent evolutions of the infrared spectra of FPh-prm/sphingomyelin (SM) mixtures were analyzed using principal component analysis (PCA). It has been postulated that the distinct anti-MDR activity of FPh-prm could be related to its ability to affect the modification of SM membranes. A reduction in the temperature of the chain-melting phase transition was observed in FPh-prm-mixed SM membranes together with the loosing of the phase transition cooperativity. Increasing the temperature led to the trans to gauche isomerization of FPh-prm-rich lipid membranes, which resulted in the gradual release of FPh-prm from the lipid membrane to the water phase. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) correlation spectroscopy, applied to one-dimensional solid-state cross polarization magic angle spinning (CP-MAS) 13 C nuclear magnetic resonance (NMR), Fourier transform infrared coupled to attenuated total reflectance (FTIR-ATR), and the combination of CP-MAS 13 C NMR and FTIR-ATR data, has been used to glean new structural information on the most hydrophobic water-soluble organic matter (WSOM) from fine urban air particles collected during different seasons. CP-MAS 13 C NMR analysis confirmed that unsubstituted saturated aliphatics, aromatics, oxygenated aliphatics, and carboxylic acids accounted for most (84–92%) of the characterized carbon functional groups. Applying 2D correlation spectroscopy to CP-MAS 13 C NMR and FTIR-ATR spectra indicates an increase in the contribution of hydroxyl and carboxylic groups to the aliphatic component with increasing air temperature, suggesting the photo-chemical origin of these WSOM structures. Urban samples from colder periods are clearly impacted by biomass combustion sources, although the presence of aged and processed organic aerosols cannot be ruled out. Using 2D FTIR- 13 C NMR hetero-spectral correlation spectroscopy, it has been demonstrated that the studied WSOM samples consists of at least two different classes of compounds: (i) an aliphatic component rich in both carboxylic and hydroxyl functional groups, and (ii) lignin-derived structures. [ABSTRACT FROM AUTHOR]

Six hundred thirty-two honey samples from Croatia were analyzed by reference methods (physicochemical and melissopalynological analyses), from which 506 were assigned to one of nine unifloral honey types (black locust, sweet chestnut, lime, sage, heath, mandarin, false indigo, immortelle and winter savory). Vibrational spectra of honey samples recorded using Fourier transform infrared (FTIR) spectroscopy and attenuated total reflection (ATR) technique were subjected to comprehensive chemometric assessment involving optimization of data preprocessing and multivariate statistical analyses, namely principal component analysis, partial least squares regression, partial least squares-discriminant analysis and receiver operating characteristic (ROC) analysis. A specially designed hybrid multidimensional model (partial least squares-linear discriminnat analysis) was used to assess a relationship between honey IR spectra and relative frequencies of pollen grains (pollen spectrum) present in selected honey samples. The study demonstrated that a targeted spectral profiling, i.e., preprocessing of a fingerprint spectral region (1,800-700 cm) by particular Savitzky-Golay filtering parameters and ROC modelling approach, enables accurate classification (100 % correct classification) of unifloral honeys by their botanical origin with low misclassification risk (MR = 0.099) and negligible small number of misclassified samples (1-2 per class-honey type). The results have also revealed good predictive strength of FTIR-ATR spectroscopy for melissopalynologycal data. [ABSTRACT FROM AUTHOR]

Objects of this study are the wooden artifacts discovered in the archaeological excavation of Mephitis goddess sanctuary in the Ansanto Valley (Rocca San Felice – AV, Southern Italy). At the moment of discovery, in the mid of last century, woods were waterlogged and mineralized, and they were restored to allow their preservation. Purpose of this work was the wood identification, in order to gain information on some technological aspects, and the analysis of wood preservation state. Wood species were identified by means of magnifiers or optical and scanning electron microscopes, while the state of preservation was studied through microscopy and chemical analyses (FTIR-ATR, ash content and pH measurement). Four different taxa have been identified with certainty among all the findings: Quercus sp. , Fagus sylvatica L., Rosaceae, Populus/Salix . It was not possible to identify the wood of all the findings, because some sampled fragments were too small or because of the deformation of wood tissues. The state of preservation showed a great variability over the analyzed findings. A general damage degree was observed, sometimes also macroscopically visible. The polarized light microscope and FTIR-ATR spectroscopy demonstrated the absence of cellulose in the analyzed samples. The wood cell wall was not detectable by means of SEM because it is completely covered by restoration material. Because of the lack of visibility, it was impossible to identify the type of biological damage occurred to the wood. [ABSTRACT FROM AUTHOR]

The degree of polymer crystallinity and water content on the surfaces and in the bulk of poly(vinyl alcohol) (PVA) cryogels prepared from aqueous salt solutions were determined as functions of KCl concentration using FTIR-ATR spectroscopy. It was found that the degree of PVA crystallinity increased with increasing KCl concentration and was much greater in the cryogel bulk than on its surfaces. Addition of salt at a concentration of 1.3 M increased the degree of polymer crystallinity on the cryogel surfaces by 1.6-2.3 times whereas the crystallinity in the bulk increased by 3.3-4 times. The cryogel water contents on the surfaces and in the bulk were approximately equal and were practically independent of the salt concentration. [ABSTRACT FROM AUTHOR]

Fluphenazine (FPh) belongs to the phenothiazine family of compounds and exhibits a wide variety of biological effects, including antimutagenic, proapoptotic, antiproliferative and anti-multidrug resistance (MDR) activities. The ability of FPh to interact with lipid membranes can have a significant impact on its biological activities. However, the mechanisms involved in the interaction of FPh with lipid membranes are poorly understood. FTIR–ATR spectroscopy has been used in this study to visualize the interactions between FPh and a model lipid bilayer composed of 1,2-dipalmitoyl- sn -glycero-3-phosphocholine (DPPC). Subsequent interpretation of the temperature-dependent FTIR spectra obtained for FPh:DPPC systems containing different concentrations of FPh was efficiently supported by principal component analysis. [ABSTRACT FROM AUTHOR]