Showing papers by "University of Trás-os-Montes and Alto Douro published in 2005"

Prevalence and risk factors for overweight and obesity in Portuguese children

Abstract: Aim: To identify risk factors for overweight and obesity in Portuguese children. Methods: A cross-sectional study of children 7 to 9.5 y old was performed between October 2002 and June 2003. A total of 2274 girls and 2237 boys were observed. Weight and height were measured, and parents filled out a questionnaire about family characteristics. Overweight and obesity, using age- and sex-specific body mass index (BMI) cut-off points as defined by the International Obesity Taskforce, were used. Results: After adjustment for age and sex, the odds ratio for childhood obesity increased by television viewing (reference 0-2 h; 2-3 h: 1.51; 3-4 h: 1.72; ^4 h: 1.63), paternal obesity (reference 11 h/d: 0.39), paternal education (reference primary school; secondary: 0.91; university: 0.42), matemal education (reference primary school; secondary: 1.13; university: 0.56), being a single child (reference yes; no: 0.56) and family size (reference one child; two children: 0.59; three children: 0.44; more than four children: 0.37). Conclusion: Our data support the perspective that education about energy intake and energy expenditure should be used much earlier in those families with high-risk children, namely those with high parental BMI or high birthweight. Protective factors were parental education and family size.

Partial replacement of fish oil by soybean oil on lipid distribution and liver histology in European sea bass (Dicentrarchus labrax) and rainbow trout (Oncorhynchus mykiss) juveniles

Abstract: Summary A 12-week feeding trial was conducted to evaluate the effects of fish oil replacement by soybean oil, on lipid distribution and liver histology of two commercially important finfish species: rainbow trout (Oncorhynchus mykiss) and European sea bass (Dicentrarchus labrax). Sea bass (16.2 ± 0.5 g; mean ± SD) and rainbow trout (52.1 ± 0.5 g) juveniles were fed one of three isonitrogenous (500 g kg−1 CP) and isoenergetic (19 kJ g−1) diets, containing 0% (control, diet A), 25% (diet B) and 50% (diet C) soybean oil. At the end of the experiment, lipid deposition was evaluated in muscle, liver and viscera. Cholesterol and triglycerides levels were also determined in plasma. Tissue total, neutral and polar lipid composition (g kg−1 total lipids) showed no significant differences within species, regardless the dietary treatment. The same trend was observed for plasma parameters (P > 0.05). Viscera were the preferential tissue of lipid deposition, with 252–276 and 469–513 g kg−1 total lipid content in trout and sea bass, respectively. Dietary fish oil replacement had no effect on either hepatic lipid droplets accumulation or degree and pattern of vacuolization in the observed liver sections. These data suggest that both sea bass and trout can be fed diets containing up to 50% soybean oil without adverse effects on tissue lipid composition or liver histology.

Copper induced alterations of biochemical parameters in the gill and plasma of Oreochromis niloticus.

Abstract: The main objective of this study was to determine the effects of copper exposure on copper accumulated in branchial tissue, gill Na+/K+-ATPase activity and plasma Na+, Cl-, osmolality, protein, glucose and cortisol, in Oreochromis niloticus. Fish were experimentally exposed to 40 and 400 microg L(-1) of waterborne copper and sacrified after 0, 3, 7, 14 and 21 days. Copper accumulation and Na+/K+-ATPase activity were determined in branchial tissue, whereas osmolality, Na+, Cl-, protein, glucose and cortisol concentrations were measured in plasma samples. Gill copper accumulation increased linearly with exposure time and concentration, whereas gill Na+/K+-ATPase activity was maximally inhibited after 3 days of exposure and showed a significant negative correlation with copper tissue levels. Plasma Cl- values decreased with time of exposure but only at 400 microg L(-1) of copper. Plasma Na+, protein and osmolality decreased with exposure time at the highest copper concentration tested, whereas at 40 microg L(-1) of copper this effect was only observed after 21 days of exposure. Plasma glucose and cortisol levels increased in a dose and time dependent manner, while showing complex fluctuations during the intermediate exposure times. In conclusion, copper induces an early maximum inhibition of gill Na+/K+-ATPase activity in O. niloticus. The subsequent slow decrease in ion plasma levels was related to compensatory mechanisms involving a non-specific stress response that appeared overcome at long-term exposures.

Flow and Forced Convection Heat Transfer in Crossflow of Non-Newtonian Fluids over a Circular Cylinder

Abstract: The steady and incompressible flow of power-law type non-Newtonian fluids across an unconfined, heated circular cylinder is investigated numerically to determine the dependence of the individual drag components and of the heat transfer characteristics on power-law index (0.5 ≤ n ≤ 1.4), Prandtl number (1 ≤ Pr ≤ 100), and Reynolds number (5 ≤ Re ≤ 40). The momentum and energy equations are expressed in the stream function/vorticity formulation and are solved using a second-order accurate finite difference method to determine the pressure drag and frictional drag as well as the local and surface-averaged Nusselt numbers and to map the temperature field near the cylinder. The accuracy of the numerical procedure is established using previously available numerical and analytical results for momentum and heat transfer in Newtonian and power-law fluids. The results reported herein provide fundamental knowledge of the flow and heat transfer behavior for the flow of non-Newtonian fluids over a circular cylinder; t...

Weather regimes and their connection to the winter rainfall in portugal

Abstract: Wintertime rainfall over Portugal is strongly coupled with the large-scale atmospheric flow in the Euro-Atlantic sector. A K-means cluster analysis, on the space spanned by a subset of the empirical orthogonal functions of the daily mean sea-level pressure fields, is performed aiming to isolate the weather regimes responsible for the interannual variability of the winter precipitation. Each daily circulation pattern is keyed to a set of five weather regimes (C, W, NAO−, NAO+ and E). The dynamical structure of each regime substantiates the statistical properties of the respective rainfall distribution and validates the clustering technique. The C regime is related to low-pressure systems over the North Atlantic that induce southwesterly and westerly moist winds over the country. The W regime is characterized by westerly disturbed weather associated with low-pressure systems mainly located over northern Europe. The NAO− regime is manifested by weak low-pressure systems near Portugal. The NAO+ regime corresponds to a well-developed Azores high with generally settled and dry weather conditions. Finally, the E regime is related to anomalous strong easterly winds and rather dry conditions. Although the variability in the frequencies of occurrence of the C and NAO− regimes is largely dominant in the interannual variability of the winter rainfall throughout Portugal, the C regime is particularly meaningful over northern Portugal and the NAO− regime acquires higher relevance over southern Portugal. The inclusion of the W regime improves the description of the variability over northern and central Portugal. Dry weather conditions prevail in both the NAO+ and E regimes, with hardly any exceptions. The occurrence of the NAO+ and the NAO− regimes is also strongly coupled with the North Atlantic oscillation. Copyright  2005 Royal Meteorological Society.

Occurrence of salmonella in the ileum, ileocolic lymph nodes, tonsils, mandibular lymph nodes and carcasses of pigs slaughtered for consumption.

Abstract: This study evaluates the occurrence of Salmonella in pork carcasses and in some risk tissues (ileum, ileocolic and mandibular lymph nodes and tonsils), that can be involved in Salmonella contamination during slaughter. Salmonella was identified in 27 (26.7%) pigs and in 13 (12.9%) carcasses. From these positive carcasses, 69.2% presented the same serotype as that identified in the corresponding pig, which emphasize the pigs importance as a source of Salmonella during the slaughter, suggesting that measures should be taken at the level of pig production in order to reduce the slaughtering of Salmonella-positive animals. The highest value of Salmonella occurrence was reached in the ileocolic lymph nodes (18.8%) and in the ileum (13.9%), representing Salmonella potential faecal source during pork processing at the abattoir. In these samples, a high level of Salmonella was observed in the ileocolic lymph nodes in comparison with the ileum. The mandibular lymph nodes (12.9%) also presented a higher occurrence in comparison with the tonsils (9.9%). These results indicate that the lymph nodes analysis could be more sensitive in the detection of Salmonella than the closer drainage tissue. Otherwise, the presence of Salmonella in the lymph nodes indicates lymphatic spread of the organism, which reflects an increased risk of pork contamination. These results also indicate that, in order to achieve a better control of Salmonella contamination during the slaughter process, it is important to consider the improvement of the evisceration practices and the tonsils as well the extraction of mandibular lymph nodes after slaughter.

Enzymatic kinetic of cellulose hydrolysis: inhibition by ethanol and cellobiose.

Abstract: The ethanol effect on the Trichoderma reesei cellulases was studied to quantify and clarify this inhibition type. To determine inhibition parameters of crude cellulase and purified exoglucanase Cel7A, integrated Michaelis-Menten equations were used assuming the presence of two inhibitors: cellobiose as the reaction product and ethanol as a possible bioproduct of cellulose fermentation.

Characterization of Antibiotic Resistance Genes and Virulence Factors in Faecal Enterococci of Wild Animals in Portugal

Abstract: Summary Antibiotic susceptibility was tested in 140 non-selected enterococci (73 Enterococcus faecalis, 45 E. faecium and 22 of other species) recovered from faecal samples of 77 wild animals in Portugal. Susceptibility testing for 11 antibiotics (vancomycin, teicoplanin, ampicillin, streptomycin, gentamicin, kanamycin, chloramphenicol, tetracycline, erythromycin, quinupristin–dalfopristin and ciprofloxacin) was determined by disk diffusion and agar dilution methods. Forty-four isolates (31.4%) showed susceptibility to all the antibiotics tested (5.5% of E. faecalis; 62.2% of E. faecium; and 78.6% of E. hirae). Neither ampicillin-resistance nor acquired-vancomycin-resistance was detected and 1.4% of the isolates showed high-level-resistance for gentamicin or streptomycin. Tetracycline and erythromycin resistances were shown in 28.6% and 20.1% of the isolates, respectively. Antibiotic resistance genes were studied by polymerase chain reaction (PCR) and sequencing and tet(M) + tet(L), erm(B) or aac(6′)-aph(2′′) genes were detected in most of tetracycline-, erythromycin- or gentamicin-resistant enterococci respectively. Genes encoding virulence factors were studied by PCR and a wide variety of virulence genes were detected in most of E. faecalis isolates but were rarely found in E. faecium and not detected in the other species. The prevalence of genes encoding virulence factors in E. faecalis was as follows: cpd (98.6%), gelE (75.3%), agg (30.1%), fsr (17.8%), ace (9.6%) and esp (4.1%). Low percentages of antibiotic resistance was found in the faecal enterococci of wild animals but a wide variety of virulence genes were detected among E. faecalis isolates although were rare in the other species.

Structure–photoluminescence relationship in Eu(III) β-diketonate-based organic–inorganic hybrids. Influence of the synthesis method: carboxylic acid solvolysis versus conventional hydrolysis

Abstract: Organic–inorganic hybrids incorporating Eu(nta)3·bpy (where nta and bpy stand for 1-(2-naphthyl)-4,4,4-trifluoro-1,3-butanedionate and 2,2′-bipyridine, respectively) were prepared either by acetic acid solvolysis or a conventional hydrolysis sol–gel route. The host framework of these materials, classed as di-ureasil, consists of a siliceous network grafted, through urea cross-linkages, to both ends of poly(ethylene oxide) chains. The resulting Eu(III)-based di-ureasils were investigated by small angle X-ray scattering, X-ray diffraction, Fourier transform mid-infrared spectroscopy, 29Si and 13C nuclear magnetic resonance, and photoluminescence spectroscopy, with particular attention paid to the effect of the adopted synthesis strategy on the relationship between structure and emission properties. The dimensions and the degree of condensation of the siloxane nanodomains depend noticeably on the synthesis route and the overall emission quantum yield decreases from 15 (conventional hydrolysis) to 6% (solvolysis route). The broad white-light emission typical of the di-ureasil host was not detected here suggesting, therefore, the activation of energy transfer channels between the hybrid host's emitting centres and the Eu(III) ions. As the first coordination shell of Eu(III) is essentially independent of the synthesis method employed, the significant decrease in the emission quantum yield for the di-ureasil prepared by acetic acid solvolysis might be explained by the interaction between the hybrid emitting centres and the nta ligand levels, favouring a larger non-radiative transition probability.

Phenotypic, genotypic, and phylogenetic discrepancies to differentiate Aeromonas salmonicida from Aeromonas bestiarum.

Abstract: The taxonomy of the "Aeromonas hydrophila" complex (comprising the species A. hydrophila, A. bestiarum, A. salmonicida, and A. popoffii) has been controversial, particularly the relationship between the two relevant fish pathogens A. salmonicida and A. bestiarum. In fact, none of the biochemical tests evaluated in the present study were able to separate these two species. One hundred and sixteen strains belonging to the four species of this complex were identified by 16S rDNA restriction fragment length polymorphism (RFLP). Sequencing of the 16S rDNA and cluster analysis of the 16S-23S intergenic spacer region (ISR)-RFLP in selected strains of A. salmonicida and A. bestiarum indicated that the two species may share extremely conserved ribosomal operons and demonstrated that, due to an extremely high degree of sequence conservation, 16S rDNA cannot be used to differentiate these two closely related species. Moreover, DNA-DNA hybridization similarity between the type strains of A. salmonicida subsp. salmonicida and A. bestiarum was 75.6 %, suggesting that they may represent a single taxon. However, a clear phylogenetic divergence between A. salmonicida and A. bestiarum was ascertained from an analysis based on gyrB and rpoD gene sequences, which provided evidence of a lack of congruence of the results obtained from 16S rDNA, 16S-23S ISR-RFLP, DNA-DNA pairing, and biochemical profiles.

Estimation in vivo of the body and carcass chemical composition of growing lambs by real-time ultrasonography.

Abstract: The relationship between ultrasound measurements and empty body and carcass chemical composition was investigated. A 500-V real-time ultrasound with a 7.5-MHz probe combined with image analysis was used to make in vivo measurements to predict the empty body and carcass chemical composition of 31 female lambs of two genotypes, ranging in BW from 18.2 to 48.9 kg. Eleven ultrasound measurements of s.c. fat, muscle, and tissue depth were taken at four different sites (over the 13th thoracic vertebra, between the 3rd and 4th lumbar vertebrae, at the 3rd sternebra of the sternum, and over the 11th rib, 16 cm from the dorsal midline). The single best predictor of empty body fat quantity and energy value was the s.c. fat depth over the 13th thoracic vertebra (r 2 = 0.904 and 0.912; P < 0.01, respectively). Body weight was used with ultrasound measurements in multiple regression equations to establish the best independent variables combination for predicting chemical composition. Results showed that BW and two of the three ultrasound measurements (s.c. fat depth over the 13th thoracic vertebra, between the 3rd and 4th lumbar vertebrae, and tissue depth over the 11th rib, 16 cm from the dorsal midline), explained 94.7 to 98.7% (P < 0.01) of the quantity of water and fat and the energy value variation in the empty body and carcass. Body weight per se was the best predictor of the quantity of protein, accounting for 97.5 and 96.8% (P < 0.01) of the variation observed in the empty body and carcass, respectively. The results of this study suggest that BW and some ultrasound measurements combined with image analysis, particularly subcutaneous fat depth over the 13th thoracic vertebra, allow accurate prediction of empty body and carcass chemical composition in lambs.

Cox-2 levels in canine mammary tumors, including inflammatory mammary carcinoma: clinicopathological features and prognostic significance.

Abstract: Cyclo-oxygenase (Cox-2) plays an important role in mammary carcinogenesis, nevertheless, its role in canine mammary tumors, and particularly in inflammatory mammary carcinoma (IMC), is unknown. Tumor Cox-2 levels were analyzed by enzyme immunoassay, in post-surgical tumor homogenates of 129 mammary tumors (62 dysplasias and benign tumors, 57 malignant non-IMC and 10 IMC) from 57 female dogs. The highest Cox-2 values were detected in the IMC group. In non-IMC malignant tumors, high values of Cox-2 were related to skin ulceration (p < 0.001) and tumor size (p < 0.001). The follow-up study revealed that high Cox-2 levels were related with recurrence (p = 0.002), metastases (p < 0.001), disease-free survival (p < 0.001) and overall survival (p < 0.001). This study demonstrates an association between intra-tumor Cox-2 levels and poor prognosis. The high levels found in IMC cases could indicate a special role of Cox-2 in the inflammatory phenotype and open the possibility of additional new therapeutic approaches in this special type of mammary cancer in humans and dogs.

Magnetic entropy change ofPr1−xCaxMnO3manganites(0.2⩽x⩽0.95)

Abstract: In the present work we analyze the magnetic entropy change $\ensuremath{\Delta}{S}_{\mathrm{M}}$ of the ${\mathrm{Pr}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}\mathrm{Mn}{\mathrm{O}}_{3}$ manganites, for a wide range of Ca concentrations $(0.20\ensuremath{\leqslant}x\ensuremath{\leqslant}0.95)$. The results for the samples with $0.20lx\ensuremath{\leqslant}0.30$ present the usual behavior expected for ferromagnetic systems, peaking at the Curie temperature ${T}_{\mathrm{C}}$. In contrast, for the charge-ordered antiferromagnetic samples $(0.30lxl0.90)$, an anomalous magnetic entropy change starts around the charge-ordering temperature ${T}_{\mathrm{CO}}$, persisting for lower values of temperature. This effect is associated to a positive contribution to the magnetic entropy change due to the charge-ordering $\ensuremath{\Delta}{S}_{\mathrm{CO}}$, which is superimposed to the negative contribution from the spin-ordering $\ensuremath{\Delta}{S}_{\text{spin}}$; that is described using a mean-field approximation. Supposing these contributions, we could also appraise $\ensuremath{\Delta}{S}_{\mathrm{CO}}^{\mathrm{max}}$ as a function of Ca content, which vanishes for the limits $x\ensuremath{\sim}0.30$ and 0.90 and presents a deep minimum around $x\ensuremath{\sim}0.50$, with two maxima at $x\ensuremath{\sim}0.35$ and 0.65. We conclude that for $xg0.65$ only the magnetic order governs the charge ordering, contrarily to $xl0.65$, where there are more than one mechanism ruling the charge ordering. Moreover, for the samples with phase coexistence $(0.30lx\ensuremath{\leqslant}0.40)$, we found extremely large values for the magnetic entropy change at low temperatures. Finally, for $xg0.90$, we found usual magnetic entropy change curves, peaking at the N\'eel temperature ${T}_{\mathrm{N}}$.

Validation of the alkane technique to estimate diet selection of goats grazing heather–gorse vegetation communities

Abstract: The effect of n-alkane faecal recovery on the accuracy of diet composition estimates, when increasing the number of diet components, was studied. Seven dietary treatments, composed of different proportions of herbaceous (Lolium perenne and Trifolium repens) and woody species (Erica umbellata, Erica cinerea, Calluna vulgaris, Erica arborea and Ulex gallii) were offered to 28 goats housed in metabolism crates. Diet composition was estimated from alkane concentrations in diet and faeces, with and without correction for incomplete faecal recoveries, using least-squares procedures and was compared with the known diet proportions. There were no significant differences between measured proportions of dietary components and those estimated with alkanes when applying the faecal recovery corrections. In contrast, the proportions calculated without faecal recovery correction differed significantly (p < 0.05) from the actual proportions, overestimating feeds with higher content of long-chain n-alkanes. The diet composition affected significantly the faecal recovery of alkanes if there were significant differences on in vivo digestibility. The n-alkane faecal recoveries decreased as the diet digestibility increased. The results obtained show that the application of the alkane methodology for grazing animals should be preceded by calculation of the actual alkane faecal recoveries for each type of vegetation community and experimental conditions. Copyright © 2005 Society of Chemical Industry

BOX-PCR is an adequate tool for typing Aeromonas spp.

Abstract: PCR-based methods of fingerprinting take advantage of the presence of repetitive sequences that are interspersed throughout the genome of diverse bacterial species. They include the repetitive extragenic palindromic (REP) sequence, the enterobacterial repetitive intergenic consensus sequence (ERIC) and the 154-bp BOX element. The combination of the three methods is used for fine discrimination of strains and is designated as rep-polymerase chain reaction (PCR). REP-PCR and ERIC-PCR have been shown to be useful for typing Aeromonas strains. To our knowledge, rep-PCR fingerprinting method using the BOXA1R primer has never been tested on aeromonads. In this study, the BOX-PCR fingerprinting technique was evaluated for the discrimination of strains of some Aeromonas species. All strains were typeable and the majority showed unique banding patterns. Four strains from culture collections were used to investigate the reproducibility of the method. According to our results, BOX-PCR fingerprinting is applicable for typing of Aeromonas strains and can be considered as a useful complementary tool for epidemiological studies of members of this genus.

Analysis of Recent Fatigue Data Using the Structural Stress Procedure in ASME Div. 2 Rewrite

Abstract: In support of the ASME Div 2 Rewrite, a master S-N curve approach has been developed using a mesh-insensitive structural stress procedure for fatigue evaluation of welded components. The effectiveness of the master S-N curve approach has been demonstrated in a number of earlier publications for many joint types and loading conditions for pipe and vessel components as well as plate joints. To further validate the structural stress method, a series of recent test data (small weld details and a full-scale vessel) published by De Jesus et al. (2004, Fatigue and Fracture of Engineering Materials and Structures, 27, pp. 799-810) were analyzed in this paper. A comparative assessment of various existing procedures and their effectiveness in correlating the fatigue test data by De Jesus is also presented. These assessment procedures include current ASME Sec. VIII Div 2, weld classification approach in PD 5500, and the surface extrapolation-based hot spot stress approach in recently approved European EN 13445 Standards.

A new aluminum tolerance gene located on rye chromosome arm 7RS

Abstract: Rye has one of the most efficient groups of genes for aluminum tolerance (Alt) among cultivated species of Triticeae. This tolerance is controlled by, at least, three independent and dominant loci (Alt1, Alt2, and Alt3) located on chromosome arms 6RS, 3RS, and 4RL, respectively. The segregation of Alt genes and several random amplified polymorphic DNA (RAPD), Secale cereale inter-microsatellite (SCIM), and Secale cereale microsatellite (SCM) markers in three F2 between a tolerant cultivar (Ailes) and a non-tolerant inbred line (Riodeva) were studied. The segregation ratio obtained for aluminum tolerance in the three F2 populations analyzed was 3:1 (tolerant:non-tolerant), indicating that tolerance is controlled by one dominant locus. SCIM8111376 was linked to an Alt gene in the three F2 populations studied, and three different SCIMs and one RAPD (SCIM8111376, SCIM812626, SCIM8121138, and OPQ4725) were linked to the Alt gene in two F2 populations. This result indicated that the same Alt gene was segregating in the three crosses. SCIM8191434 and OPQ4578 linked to the tolerance gene in one F2 population were located using wheat–rye ditelosomic addition lines on the 7RS chromosome arm. The Alt locus is mapped between SCIM8191434 and the OPQ4578 markers. Two microsatellite loci (SCM-40 and SCM-86), previously located on chromosome 7R, were also linked to the Alt gene. Therefore, the Alt gene segregating in these F2 populations is new and probably could be orthologous to the Alt genes located on wheat chromosome arm 4DL, on barley chromosome arm 4HL, on rye chromosome arm 4RL, and rice chromosome 3. This new Alt gene located on rye chromosome arm 7RS was named Alt4. A map of rye chromosome 7R with the Alt4 gene, 16 SCIM and RAPD, markers and two SCM markers was obtained.

Planar and UV written channel optical waveguides prepared with siloxane–poly(oxyethylene)–zirconia organic–inorganic hybrids. Structure and optical properties

Abstract: Organic–inorganic hybrids were prepared using ureapropyltriethoxysilane, methacryloxypropyltrimethoxysilane and acrylic acid modified zirconium(IV) n-propoxide precursors and were characterized by small angle X-ray scattering, X-ray diffraction and photoluminescence spectroscopy. The results indicate an effective interaction between the zirconium-based nanoparticles and the siliceous nanodomains that induces changes in the hybrids' emission features. Planar waveguides were obtained by spin-coating of the prepared sols on sodalime and silica substrates. Refractive index, thickness, number of propagating modes, and attenuation coefficient were measured at 543.5, 632.8 and 1550 nm by the prism coupling technique. The synergism between the two hybrid precursors resulted in monomode planar waveguides with low losses in the infrared (from 0.6–1.1 dB cm−1) which also support a number of propagating modes in the visible (losses from 0.4–1.5 dB cm−1). Channel waveguides were also obtained by UV photopatterning using amplitude or phase masks and propagating modes were observed at 1550 nm.

Local structure and near-infrared emission features of neodymium-based amine functionalized organic/inorganic hybrids.

Abstract: Nd3+-based organic/inorganic hybrids have potential application in the field of integrated optics. Attractive sol-gel derived di-urea and di-urethane cross-linked poly (oxyethylene) (POE)/siloxane hybrids (di-ureasils and di-urethanesils, respectively) doped with neodymium triflate (Nd(CF3SO3)(3)) were examined by Fourier transform mid-infrared (FT-IR), Raman (FT-Raman), Si-29 magic-angle spinning (MAS) nuclear magnetic resonance (NMR) and photoluminescence spectroscopies, and small-angle X-ray scattering (SAXS). The goals of this work were to determine which cation coordinating site of the host matrix (ether oxygen atoms or carbonyl oxygen atoms) is active in each of the materials analyzed, its influence on the nanostructure of the samples and its relation with the photoluminescence properties. The main conclusion derived from this study is that the hydrogen-bonded associations formed throughout the materials play a major role in the hybrids nanostructure and photoluminescence properties.