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Ferrites have been widely studied for their use in the biomedical area, mostly due to their magnetic properties, which gives them the potential to be used in diagnostics, drug delivery, and in treatment with magnetic hyperthermia, for example. In this work, KFeO 2 particles were synthesized with a proteic sol-gel method using powdered coconut water as a precursor; this method is based on the principles of green chemistry. To improve its properties, the base powder obtained was subjected to multiple heat treatments at temperatures between 350 and 1300 °C. The samples obtained underwent structural, morphological, biocompatibility, and magnetic characterization. The results show that upon raising the heat treatment temperature, not only is the wanted phase detected, but also the secondary phases. To overcome these secondary phases, several different heat treatments were carried out. Using scanning electron microscopy, grains in the micrometric range were observed. Saturation magnetizations between 15.5 and 24.1 emu/g were observed for the samples containing KFeO 2 with an applied field of 50 kOe at 300 K. From cellular compatibility (cytotoxicity) assays, for concentrations up to 5 mg/mL, only the samples treated at 350 °C were cytotoxic. However, the samples containing KFeO 2 , while being biocompatible, had low specific absorption rates (1.55-5.76 W/g).

Additive manufacturing technologies have numerous advantages over conventional technologies; nevertheless, their production process can lead to high residual stresses and distortions in the produced parts. The use of numerical simulation models is presented as a solution to predict the deformations and residual stresses resulting from the printing process. This study aimed to predict the tensions and distortions imposed in the gear repair process by directed energy deposition (DED). First, the case study proposed by National Institute of Standards and Technology (NIST) was analyzed to validate the model and the numerically obtained results. Subsequently, a parametric study of the influence of some of the parameters of DED technology was carried out. The results obtained for the validation of the NIST benchmark bridge model were in agreement with the results obtained experimentally. In turn, the results obtained from the parametric study were almost always in line with what is theoretically expected; however, some results were not very clear and consistent. The results obtained help to clarify the influence of certain printing parameters. The proposed model allowed accounting for the effect of residual stresses in calculating the stresses resulting from gear loading, which are essential data for fatigue analysis. Modeling and simulating a deposition process can be challenging due to several factors, including calibrating the model, managing the computational cost, accounting for boundary conditions, and accurately representing material properties. This paper aimed to carefully address these parameters in two case studies, towards reliable simulations.

Carbonaceous materials derived from biomass have been used as sustainable platforms for the growth of ZnO particles aiming the production of functional composite fillers. Kidney-bean pods were pyrolyzed by applying an experimental design that demonstrates that the specific surface area (S BET ) of biochar is improved with increasing pyrolysis temperature combined with a short air-oxidation time. Meanwhile, the graphitization degree and the electrical conductivity (EC) of biochars were negatively affected by increasing the air-oxidation time. The biochar sample with the higher EC and the one with the higher S BET were selected to be functionalized with ZnO particles by a solvothermal methodology, obtaining composites with an EC and S BET properties superior to the ZnO-rGO composite, in addition to a similar antibacterial activity. The developed ZnO-biochar composite structures, which are more ecological and biocompatible than the ZnO composites derived from graphene sheets, can be applied as electrically conductive and active fillers.

Bionanocomposite materials have been designed as a promising route to enhance biopolymer properties, especially for food packaging application. The present study reports the preparation of bionanocomposite films of alginate with different loadings of pure reduced graphene oxide (rGO) or of mixed zinc oxide-rGO (ZnO-rGO) fillers by solvent casting. Sepiolite is used to make compatible rGO with the hydrophilic matrix. The addition of fillers to alginate matrix maintains the low water solubility promoted by the calcium chloride treatment, and, additionally, they demonstrate a weaker mechanical properties, and a slight increase in water vapor permeability and wettability. Due to the properties of ZnO-rGO, the alginate bionanocomposites show an increase of electrical conductivity with the increase of filler content. While the highest electrical conductivity (0.1 S/m) is achieved by the in-plane measurement, it is in the through-plane measurement the remarkable enhancement of almost 30 times greater than the alginate film. With 50% of ZnO-rGO filler, the bionanocomposites present the highest antioxidant and antibacterial activities. The combination of electrical conductivity with bioactive properties makes these films promising not only to extend food shelf-life but also to allow packaged food sterilization at low temperature.

Introduction: Annona coriacea Mart. (araticum) is a widely distributed tree in the cerrado. Its value is attributed principally to the consumption of its fruit which possesses a large nutritive potential. The objective was to identify the chemical profile and evaluate the antimicrobial and cytoprotective activity of the hydroethanol extract of A. coriacea Mart. (HEAC) leaves against the toxicity of mercury chloride., Materials and Methods: The characterization of components was carried out using high-performance liquid chromatography (HPLC). The minimum inhibitory concentration (MIC) was determined by microdilution method in broth with strains of Staphylococcus aureus , Escherichia coli , and Pseudomonas aeruginosa . For evaluation of the modulatory and cytoprotective activity of aminoglycoside antibiotics (gentamicin and amikacin) and mercury chloride (HgCl 2 ), the substances were associated with the HEAC at subinhibitory concentrations (MIC/8)., Results and Discussion: The HPLC analysis revealed the presence of flavonoids such as Luteolin (1.84%) and Quercetin (1.19%) in elevated concentrations. The HEAC presented an MIC ≥512 μg/mL and significant antagonistic action in aminoglycosides modulation, and it also showed cytoprotective activity to S. aureus (significance P < 0.0001) and E. coli (significance P < 0.05) bacteria against the mercury chloride heavy metal with significance, this action being attributed to the chelating properties of the flavonoids found in the chemical identification., Conclusions: The results acquired in this study show that the HEAC presents cytoprotective activity over the tested strains in vitro and can also present antagonistic effect when associated with aminoglycosides, reinforcing the necessity of taking caution when combining natural and pharmaceutical products., Summary: The hydroalcoholic extract of A. coriacea Mart. presents in vitro cytoprotective activity against the toxic effect of Hg. Abbreviations Used : HPLC-DAD: High-performance liquid chromatography with a diode array detector; MIC: Minimum inhibitory concentration; DMSO: Dimethyl sulfoxide.

Objective . To evaluate diagnosis, age of referral, karyotype, and sex of rearing of cases with disorders of sex development (DSD) with ambiguous genitalia. Methods . Retrospective study during 23 years at outpatient clinic of a referral center. Results . There were 408 cases; 250 (61.3%) were 46,XY and 124 (30.4%) 46,XX and 34 (8.3%) had sex chromosomes abnormalities. 189 (46.3%) had 46,XY testicular DSD, 105 (25.7%) 46,XX ovarian DSD, 95 (23.3%) disorders of gonadal development (DGD), and 19 (4.7%) complex malformations. The main etiology of 46,XX ovarian DSD was salt-wasting 21-hydroxylase deficiency. In 46,XX and 46,XY groups, other malformations were observed. In the DGD group, 46,XY partial gonadal dysgenesis, mixed gonadal dysgenesis, and ovotesticular DSD were more frequent. Low birth weight was observed in 42 cases of idiopathic 46,XY testicular DSD. The average age at diagnosis was 31.7 months. The final sex of rearing was male in 238 cases and female in 170. Only 6.6% (27 cases) needed sex reassignment. Conclusions . In this large DSD sample with ambiguous genitalia, the 46,XY karyotype was the most frequent; in turn, congenital adrenal hyperplasia was the most frequent etiology. Malformations associated with DSD were common in all groups and low birth weight was associated with idiopathic 46,XY testicular DSD., Competing Interests: The authors have no competing interests.

Aims: Sleep bruxism (SB) and obstructive sleep apnea syndrome (OSAS) are often observed in children and may have several health implications. The aim of this paper is to evaluate their prevalence and to test for possible associations between these two conditions., Methodology: The sample consisted of 496 children randomly selected among the preschoolers of Taubaté, Brazil; 249 (50·2%) were boys and 247 (49·8%) were girls. Diagnoses of SB and OSAS were made by clinical examinations and questionnaires filled out by the children's parents in a cross-sectional design. Analysis of variance and Chi-square tests were applied to verify possible association among the variables in question., Results: The average age was 4·49 years (SD: ±1·04 years). A total of 25·6% were diagnosed with SB, while 4·83% were diagnosed with OSAS, and only 2·82% presented both conditions. A statistical association was found between SB and OSAS (P<0·001; Chi-square test): 11·03% of subjects with SB also presented with OSAS, and 97·18% of subjects without SB did not present with OSAS. No association was found among children's gender and age and the presence of SB or OSAS., Conclusions: Within the limits of this study, SB was associated with OSAS.

Aluminum absorption leads to deposits in several tissues. In this study, we have investigated, to our knowledge for the first time, aluminum deposition in the salivary glands in addition to the resultant cellular changes in the parotid and submandibular salivary glands in a model of chronic intoxication with aluminum citrate in rats. Aluminum deposits were observed in the parotid and submandibular glands. Immunohistochemical evaluation of cytokeratin-18 revealed a decreased expression in the parotid gland with no changes in the submandibular gland. A decreased expression of α-smooth muscle actin was observed in the myoepithelial cells of both glands. The expression of metallothionein I and II (MT-I/II), a group of metal-binding proteins, which are useful indicators for detecting physiological responses to metal exposure, was higher in both glands. In conclusion, we have shown that at a certain time and quantity of dosage, aluminum citrate promotes aluminum deposition in the parotid and submandibular glands, leads to an increased expression of MT-I/II in both the glands, damages the cytoskeleton of the myoepithelial cells in both glands, and damages the cytoskeleton of the acinar/ductal cells of the parotid glands, with the submandibular glands showing resistance to the toxicity of the latter.

Objective: to understand the meanings the family attributes to the phases of the decision-making process on a cochlear implant for their child., Method: qualitative research, using Symbolic Interactionism and Grounded Theory as the theoretical and methodological frameworks, respectively. Data collection instrument: semistructured interview. Nine families participated in the study (32 participants)., Results: knowledge deficit, difficulties to contextualize benefits and risks and fear are some factors that make this process difficult. Experiences deriving from interactions with health professionals, other cochlear implant users and their relatives strengthen decision making in favor of the implant., Conclusion: deciding on whether or not to have the implant involves a complex process, in which the family needs to weigh gains and losses, experience feelings of accountability and guilt, besides overcoming the risk aversion. Hence, this demands cautious preparation and knowledge from the professionals involved in this intervention.

The prevalence of chronic disease in childhood has increased, placing families in constant contact with health professionals. In such situations the relationship with health professionals has an important role. Few scientific studies address this theme, in spite of its being highlighted as fundamental for effective interaction. The aim of this study was to characterize how the family of a child with a chronic disease perceives its relationship with health professionals. Twenty caregivers for children with chronic diseases were interviewed. The theoretical and methodological frameworks were, respectively, symbolic interactionism and thematic content analysis. The analytical process revealed four themes: role of the caregiver, stressful relationships, services and professionals, and seeking welcoming relationships. The outcomes of this interactional process, which show an incongruity of expectations and behaviors between professionals and families, are poor and generate feelings of abandonment. These can be eased through listening and understanding by other families in similar situations.

Objective: To investigate the presence of airway obstruction by determining the FEV1/FVC and FEV1/slow vital capacity (SVC) ratios., Methods: This was a quantitative, retrospective cross-sectional study. The sample comprised 1,084 individuals who underwent spirometry and plethysmography in a central hospital in Lisbon, Portugal. The study sample was stratified into six groups, by pulmonary function., Results: The analysis of the FEV1/FVC ratio revealed the presence of airway obstruction in 476 individuals (43.9%), compared with 566 individuals (52.2%) for the analysis of the FEV1/SVC ratio. In the airway obstruction, airway obstruction plus lung hyperinflation, and mixed pattern groups, the difference between SVC and FVC (SVC - FVC) was statistically superior to that in the normal pulmonary function, reduced FEF, and restrictive lung disease groups. The SVC - FVC parameter showed a significant negative correlation with FEV1 (in % of the predicted value) only in the airway obstruction plus lung hyperinflation group., Conclusions: The FEV1/SVC ratio detected the presence of airway obstruction in more individuals than did the FEV1/FVC ratio; that is, the FEV1/SVC ratio is more reliable than is the FEV1/FVC ratio in the detection of obstructive pulmonary disease.

Network and social support are resources that nursing can offer to families. This review identifies which aspects of social support are being investigated for the family of the cancer patient. Fifty one articles were found of which 70% were quantitative research and 26% were published in the last two years. The issues addressed were: Family caregivers as provider of social support; Factors that interfere with social support; Religiosity as social support as well as support coming from educative programs, group activity and technological resources. Of these papers, 49% were written by nurses, with international emphasis on needs assessment, family experiences and support offered, while national articles emphasize definition concepts and identifying family needs focusing on intervention planning.

The present study aims to analyze what the members of the nursing team think about their emotional involvement with the patients during their relationship. Data were collected through the application of an instrument to members of the nursing team (registered nurse, nursing aides and attendants). The analysis was done, at first, separately by functional categories and after that, as a whole. We concluded that, there is in nursing a policy of no involvement with the patients and that the registered nurse is the one that most verbalizes it. One of the negative factors of the involvement with the patient is the psychological suffering of the nursing team members. This leads us to identify the no involvement behavior as a collective defence mechanism against suffering.