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Polyvinyl Alcohol (PVA)/guar gum (GG) membranes with different loads of paramagnetic iron oxide Fe 3 O 4 nanoparticles were successfully electrospun using both non-alkaline and alkaline stock solutions. The nanoparticle homogeneity distribution was clearly enhanced in fibers obtained from alkaline stock solutions. This is mainly due to the interaction between GG and the metallic ion, which also leads to further dispersion of remained uncoated nanoparticles in the mixture. It was also noticed that GG favors nanoparticle stability in the mixture and contributes to nanoparticle encapsulation. X-ray results showed that all membranes were semi-crystalline. FTIR-ATR spectra showed that Fe O absorption band intensity improved with increasing nanoparticle load, reaching saturation at 3.5 mg/ml Fe 3 O 4 concentration under alkaline conditions. VSM analyses showed that the nanoparticles are paramagnetic and were successfully incorporated by the fibers. In vitro biocompatibility tests using L929 cells indicates adequate levels of cytotoxicity and cell adhesion/proliferation assays for both membranes obtained from non-alkaline and alkaline stock solutions. Therefore, they have potential for biomedical applications as biodegradable wound dressing. [ABSTRACT FROM AUTHOR]

We have gained insight into the internal degree of atomic disorder in isolated size-selected Fe nanoparticles (NPs) (~2-6 ran in size) supported on Si02/Si(l 11) and Al2O3(0001) from precise measurements of the low-energy (low-£) part of the phonon density of states [PDOS, g(E)] via 57Fe nuclear resonant inelastic x-ray scattering (NRIXS) combined with transmission electron microscopy (TEM) measurements. An intriguing size-dependent trend was observed, namely, an increase of the low-£ excess density of phonon states (as compared to the PDOS of bulk bcc Fe) with increasing NP size. This is unexpected, since usually the enhancement of the density of low-E phonon modes is attributed to low-coordinated atoms at the NP surface, whose relative content increases with decreasing NP size due to the increase in the surface-to-volume ratio. Our NPs are covered by a Ti-coating layer, which essentially restores the local neighborhood of surface Fe atoms towards bulk-like coordination, reducing the surface effect. Our data can be qualitatively explained by the existence of low-coordinated Fe atoms located at grain boundaries or other defects with structural disorder in the interior of the large NPs (~3-6 nm), while our small NPs (~2 nm) are single grain and, therefore, characterized by a higher degree of structural order. This conclusion is corroborated by the observation of Debye behavior at low energy [g(E) ~ E" with n ~ 2] for the small NPs, but non-Debye behavior (with n ~ 1.4) for the large NPs. The PDOS was used to determine thermodynamic properties of the Fe NPs. Finally, our results demonstrate that, in combination with TEM, NRIXS is a suitable technique to investigate atomic disorder/defects in NPs. We anticipate that our findings are universal for similar NPs with bcc structure. [ABSTRACT FROM AUTHOR]

Background: Previous reports have suggested that hospital resource utilization for revision total hip arthroplasty is substantially higher than that for primary total hip arthroplasty. However, current United States Medicare hospital-reimbursement policy does not distinguish between the two procedures. The purpose of this study was to compare primary and revision total hip arthroplasties with regard to actual hospital resource utilization and to identify clinical and demographic factors that are predictive of higher resource utilization associated with these procedures.Methods: We evaluated the clinical, demographic, and economic data associated with 491 consecutive unilateral primary or revision total hip arthroplasties performed by two surgeons at a single institution between January 2000 and December 2002. The distributions of various demographic, clinical, and utilization characteristics were compared between the two types of arthroplasty procedures, and multivariable linear regression techniques were used to determine independent patient characteristics that were predictive of higher costs for both the primary and the revision procedures.Results: The mean total hospital cost was $31,341 for the revision procedures compared with $24,170 for the primary procedures (p < 0.0001). The mean operative time was 41% longer for the revisions than for the primary procedures (4.5 hours compared with 3.2 hours, p < 0.0001), the mean estimated blood loss was 160% higher (1348 mL compared with 518 mL, p < 0.0001), the mean complication rate was 32% higher (29% compared with 22%, p = 0.072), and the mean length of the hospital stay was 16% longer (6.5 days compared with 5.6 days, p = 0.0005). A higher severity-of-illness score (a measure of preoperative medical health) was predictive of higher resource utilization for both primary and revision arthroplasty even after adjustment for other factors. Preoperative femoral and ace-tabular bone loss and a diagnosis of periprosthetic fracture were predictive of higher resource utilization associated with revision procedures.Conclusions: At one institution, hospital resource utilization for revision total hip arthroplasty was found to be significantly higher than that for primary arthroplasty. This information is not reflected by current United States Medicare hospital reimbursement, which is the same for all lower-extremity arthroplasty procedures, regardless of the diagnosis, the complexity of the procedure, or the patient's baseline medical health. If these findings are generalizable to other institutions, appropriate reimbursement formulas should be developed to accurately reflect the true costs of caring for patients with a failed total hip arthroplasty. [ABSTRACT FROM AUTHOR]

We have measured the phonon density of states (PDOS) of isolated bcc and fcc FexAu1-x alloy nanoclusters (NCs) by nuclear resonant inelastic x-ray scattering. Drastic deviations were observed with respect to the PDOS of bulk Fe–Au alloys. Important information on the structure and thermodynamic properties of these NCs was obtained. [ABSTRACT FROM AUTHOR]

This study presents a systematic investigation of the thermodynamic properties of free and γ-Al2O3-supported size-controlled Pt nanoparticles (NPs) and their evolution with decreasing NP size. A combination of in situ extended x-ray absorption fine-structure spectroscopy (EXAFS), ex situ transmission electron microscopy (TEM) measurements, and NP shape modeling revealed (i) a cross over from positive to negative thermal expansion with decreasing particle size, (ii) size- and shape-dependent changes in the mean square bond-projected bond-length fluctuations, and (iii) enhanced Debye temperatures (ΘD, relative to bulk Pt) with a bimodal size-dependence for NPs in the size range of ~0.8-5.4 nm. For large NP sizes (diameter d > 1.5 nm) ΘD was found to decrease toward ΘD of bulk Pt with increasing NP size. For NPs ≤ 1 nm, a monotonic decrease of ΘD was observed with decreasing NP size and increasing number of low-coordinated surface atoms. Our density functional theory calculations confirm the size- and shape-dependence of the vibrational properties of our smallest NPs and show how their behavior may be tuned by H desorption from the NPs. The experimental results can be partly attributed to thermally induced changes in the coverage of the adsorbate (H2) used during the EXAFS measurements, bearing in mind that the interaction of the Pt NPs with the stiff, high-melting temperature γ-Al2O3 support may also play a role. The calculations also provide good qualitative agreement with the trends in the mean square bond-projected bond-length fluctuations measured via EXAFS. Furthermore, they revealed that part of the ΘD enhancement observed experimentally for the smallest NPs (d ≤ 1 nm) might be assigned to the specific sensitivity of EXAFS, which is intrinsically limited to bond-projected bond-length fluctuations. [ABSTRACT FROM AUTHOR]

Quasi-elastic barrier distributions for the 16,18O+58Ni systems have been deduced from high precision measurements of their quasi-elastic excitation functions. The distribution obtained with this method for 16O+58Ni is in complete agreement with that deduced from fusion measurements. Contrary to present beliefs, these light systems present complex barrier distributions that reveal important couplings of inelastic and transfer channels to fusion. Coupled channel calculations are in good agreement with our experimental data. [Copyright &y& Elsevier]

Cassava (Manihot esculenta Crantz) is one of the most widely cultivated foods in the world and is of great socio-economic importance, especially in developing countries. It is predominantly consumed in boiled form, but also is used to produce a number of products, including cassava starch, sour starch, cassava flour and tapioca flour (hydrated cassava starch). Fungal spoilage can occur throughout the production chain, impairing both productivity and quality, as well as posing a potential risk of contamination by mycotoxins. We used multidisciplinary approaches based on phenotypic and molecular data (ITS/BenA/TEF-1a/RPB2 loci) to investigate the mycobiota of 101 samples (including roots, soil and products) collected in the state of São Paulo, Brazil. A total of 20 fungal groups/genera were morphologically characterized, and 37 different species were molecularly identified. The predominant groups in cassava tubers were Fusarium spp., Penicillium spp. and Trichoderma spp. In cassava products, the most frequent groups were Penicillium spp. and Paecilomyces spp. Potentially toxigenic species were also found, including Paecilomyces saturatus, Penicillium citrinum, P. paneum, P. brevicompactum, P. chrysogenum, Fusarium foetens and Fusarium mundagurra. In soil-cultivated cassava samples, the groups found most frequently were Penicillium spp., Cladosporium spp. and Fusarium spp. Some of the species found in cassava tubers and/or product samples were also present in the soil, including F. mundagurra, Neocosmospora solani, P. citrinum and P. brevicompactum. In general, there was a higher occurrence of Penicillium spp., Fusarium spp. and Trichoderma spp., and the predominant species were F. fabacearum and P. citrinum. The mycobiota of Brazilian cassava proved to be extremely diverse, and the occurrence of several species in cassava tubers and/or products are reported herein for the first time. Potentially toxigenic species were found in cassava tubers, cassava products and soil, showing how important it is to constantly monitor these substrates., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Since the number of antibiotic-resistant bacterial infections is growing and cases are getting worse every year, the search for new alternative bactericidal wound dressing treatments is becoming crucial. Within this context, the use of polysaccharides from plants and seeds in innovative biopolymer technologies is of key importance. In this work, bio-nano-composite guar gum/polyvinyl alcohol (PVOH) membranes loaded with aluminum-doped zinc oxide nanoparticles were produced via electrospinning. Citric acid was added to the mixture to increase spinnability. However, depending on the pH, zinc oxide nanoparticles are partially dissociated, decreasing their bactericidal efficiency. Thus, a second successful alkaline thermo-chemical regrowth step was added to the process to treat the obtained fibers. This alkaline thermo-chemical treatment reconstituted both the nanoparticles and their bactericidal properties. The Staphylococcus aureus antibacterial assay results show that the membranes obtained after the alkaline thermo-chemical treatment presented a 57% increase in growth inhibition.

Objective: To analyze trends in urinary tract infection hospitalization (cystitis, pyelonephritis, prostatitis and non-specified UTI) among patients over 65 years in Spain from 2000-2015., Methods: We conducted a retrospective observational study using the Spanish Hospitalization Minimum Data Set (CMBD), with codifications by the International Classification of Diseases (ICD-9). We collected data on sex, age, type of discharge, main diagnosis, comorbid diagnosis, length of stay, and global cost. All the hospitalizations were grouped by age into three categories: 65-74 years old, 75-84 years old, and 85 years old and above. In the descriptive statistical analysis, crude rates were defined as hospitalizations per 1,000 inhabitants aged ≥65. To identify trends over time, we performed a Joinpoint regression., Results: From 2000-2015, we found 387,010 hospitalizations coded as UTIs (54,427 pyelonephritis, 15,869 prostatitis, 2643 cystitis and 314,071 non-specified UTI). The crude rate of hospitalization for UTIs between 2000 and 2015 ranged from 2.09 in 2000 to 4.33 in 2015 Rates of hospitalization were higher in men than in women, except with pyelonephritis. By age group, higher rates were observed in patients aged 85 years or older, barring prostatitis-related hospitalizations. Joinpoint analyses showed an average annual percentage increase (AAPC) in incidence rates of 4.9% (95% CI 3.2;6.1) in UTI hospitalizations. We observed two joinpoints, in 2010 and 2013, that found trends of 5.5% between 2000 and 2010 (95% CI 4.7;6.4), 1.5% between 2010 and 2013 (95% CI -6.0;9.6) and 6.8% between 2013 and 2015 (95% CI -0.3;14.4)., Conclusions: The urinary infection-related hospitalization rate in Spain doubled during the period 2000-2015. The highest hospitalization rates occurred in men, in the ≥85 years old age group, and in non-specified UTIs. There were increases in all types of urinary tract infection, with non-specified UTIs having the greatest growth. Understanding these changing trends can be useful for health planning., Competing Interests: The authors have declared that no competing interests exist.

Galactomannan extracted from Cassia fistula seed endosperm present little data related to the its structural characterization. This study reports the chemical characterization of the galactomannan from Cassia fistula (CF) and their oxidized derivatives. The extracted CF presented a yield of 26.5% (w/w) and the intrinsic viscosity [η] was 9.73 dL/g. 1D and 2D nuclear magnetic resonance spectroscopy (NMR) confirmed that the polysaccharide has a backbone of 4-linked β-D-mannose units, and contains galactose units as pending groups. These galactose units are linked to the central core through a (1→6) linkage and the galactomannan presented Man/Gal ratio of 3.1/1. The galactomannan from Cassia fistula presents low cytotoxicity in Vero cells with a CC 50  > 1000 μg/ml. The properties of CF resemble other commercially important galactomannans such as Locust bean gum. Three oxidized derivatives of CF were produced by periodate oxidation, which were carefully characterized by different structural techniques. It was observed that as the degree of oxidation increased, there was an increase in the Man/Gal ratio and a reduction in molar mass and viscosity. The polialdehyde produced may be explored as a versality material to react with amine group of the protein and amined polysaccharide to produce biomaterials., Competing Interests: Declaration of competing interest There are no conflicts of interest to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Reconstituted cellulose films were generated using residual bacterial cellulose membranes mechanically defibrillated (RBC fibrils) recycled following wound dressing production via a dry-cast process. Arabinogalactan (AG) extracted from Pereskia aculeata leaves and/or a xyloglucan (GHXG) from Guibourtia hymenifolia seeds were incorporating into the RBC at various compositions, and new films were created using the same process. Biocomposite properties were evaluated by scanning electron microscopy, contact angle (CA), and X-ray diffraction measurements. The attachment and proliferation of murine L929 fibroblasts on RBC and RBC/Hydrocolloids (HD) were also evaluated. RBC films with 20-30% GHXG replacement improved film stability and the inclusion of HD increased microfiber aggregation and reduced porous regions. Changes in the hydrophilic characteristics were also observed and owing to the adhesion effect the inclusion of HD on RBC led to a statistically significant effect of the mechanical properties of films. The RBC/AG films supported L929 adhesion similar to that observed for commercial bacterial cellulose, indicating their potential use for biomedical applications., (Copyright © 2016. Published by Elsevier Ltd.)

In this work, polyethylene glycol (PEG), of tree distinct molar masses (200, 300 and 400 g mol(-1)), was grafted onto mercerized bacterial nanocellulose (BNCm) and applied to produce nanofilms (BNCm-PEG). The products BNCm-PEG were characterized by NMR and thermal analysis. Solid-state NMR and X-ray diffraction analyses exhibited no significant differences in index of BNCm-PEG derivatives compared to BNCm, indicating that grafting reaction did not modify the BNCm crystalline structure. The apparent contact angle of the films showed that BNCm-PEG films exhibited a pronounced increase in the polar components (BNCm: 8.1 mN m(-1) vs BNCm-PEG400: 29.4 mN m(-1)), and a decrease in dispersive components (BNCm: 41.7 mN m(-1) vs BNCm-PEG400: 35.2 mN m(-1)) of the surface free energy. The BNCm-PEG films were more hydrophilic than BNCm and retained the biocompatibility with L929 fibroblast cells culture., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Mixtures of gellan gum (GL) and a xyloglucan (XGJ) extracted from Hymenaea courbaril seeds were prepared in a solution of 0.15 mol L(-1) NaCl. Rheology measurements revealed that 2.4 g L(-1) pure GL formed a brittle hydrogel, and GL-XGJ blends showed improved pseudoplastic character with higher XGJ contents. SAXS analyses showed that the Rg dimensions ranged from 1.3 to 4.9 nm, with larger values occurring as the amount of XGJ increased, and diffusion tests indicated that better diffusion of methylene blue dye was obtained in the network with a higher XGJ content. AFM topographic images of the films deposited onto mica revealed fewer heterogeneous surfaces with increased XGJ contents. The water contact angle revealed more hydrophobic character on all of the films, and the wettability decreased with increasing amounts of XGJ. Therefore, the demonstrated benefit of using XGJ blends is the production of a soft material with improved interface properties., (Copyright © 2014 Elsevier Ltd. All rights reserved.)