Processing of porous glass ceramics from highly crystallisable industrial wastes

This study was carried out to gain understanding about the sintering behaviour of highly crystallisable industrial waste derived silicate mixtures under direct heating and rapid cooling conditions. The materials used in this study were plasma vitrified air pollution control waste and rejected pharmaceutical borosilicate glass. Powder compacts sintered under direct heating conditions were highly porous; compacts with particle size <38 μm reached a maximum density of 2.74 g cm-3 at 850°C, whereas compacts with particles of size <100 and <250 mm reached maximum densities of 2.69 and 2.72 g cm-3 at 875 and 900°C respectively. Further increase in sintering temperature resulted in a rapid decrease in density of the glass ceramics. Image analysis results were used to link the sudden drop in density to the increase in volume of microsized pores formed in the samples during sintering. In particular, compacts made from ,38 mm particles sintered at 9508C resulted in 65 vol.-% porosity with a pore size of <20 μm. Such materials can be used for sound and thermal insulation purposes

Two-parameter nonsmooth grazing bifurcations of limit cycles: classification and open problems

This paper proposes a strategy for the classification of codimension-two grazing bifurcations of limit cycles in piecewise smooth systems of ordinary differential equations. Such nonsmooth transitions (C-bifurcations) occur when the cycle interacts with a discontinuity boundary of phase space in a non-generic way. Several such codimension-one events have recently been identified, causing for example period-adding or sudden onset of chaos. Here, the focus is on codimension-two grazings that are local in the sense that the dynamics can be fully described by an appropriate Poincaré map from a neighbourhood of the grazing point (or points) of the critical cycle to itself. It is proposed that codimension-two grazing bifurcations can be divided into three distinct types: either the grazing point is degenerate, or the the grazing cycle is itself degenerate (e.g. non-hyperbolic) or we have the simultaneous occurrence of two grazing events. A careful distinction is drawn between their occurrence in systems with discontinuous states, discontinuous vector fields, or that have discontinuity in some derivative of the vector field. Examples of each kind of bifurcation are presented, mostly derived from mechanical applications. For each example, where possible, principal bifurcation curves characteristic to the codimension-two scenario are presented and general features of the dynamics discussed. Many avenues for future research are opened.

The reality of an Obesity Surgical Treatment Center in Portugal

Introduction: Obesity surgery is used as the most effective treatment for morbid obesity, with better cost-benefit, less morbidity and mortality. The present study aimed to analyze the results of a surgical center for obesity treatment and integrate them with the most recent scientific evidence. Methods: Retrospective cross-sectional observational study involving 270 patients aged 18 years or older, who underwent bariatric surgery between July 2008 and February 2020 in a private hospital in Portugal. Results: The sample presented an average age of 44 ± 12 years, being mostly female (83.7%). The average pre-surgery Body Mass Index was 41.1 ± 4.9 kg/m2 . The most performed surgery was Gastric Bypass (80.4%), followed by Gastric Banding (14.8%) and Gastric Sleeve (4.8%). One month after surgery, there was a percentage of excess weight lost (% EWL) of 25.2 ± 9.6%. After 6 months, there was an average % EWL of 67.2 ± 23.2%. One year after surgery, the average % EWL was 75.7 ± 25.7%, the average Body Mass Index was 29.3 ± 4.6 kg/m2 and the average weight loss percentage was 29.5 ± 9.4%. Conclusion: Gastric Bypass is the mostly performed surgery, because it is the Gold Standard method for surgical treatment of obesity in this center. On average, all surgeries performed have extremely positive results of excess weight lost. After 1 year, patients maintained an average weight loss percentage of 29.5 ± 9.4%, in line with data presented in a study that estimated an average recorded weight loss percentage of 28.9%. Data like those presented by the American Society for Nutrition (ASN), the Obesity Action Coalition (OAC), the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), the International Society for the Perioperative Care of the Obese Patient (ISPCOP) and the American Society for Parenteral and Enteral Nutrition (ASPEN) (2019), indicate a target weight loss percentage between 20 and 45%.info:eu-repo/semantics/publishedVersio

Food Intake in Pregnant Women with Gestational Diabetes Mellitus

Rationale: The aim of the present study was to verify the fulfillment of the nutritional requirements of macronutrients of pregnant women diagnosed with Gestational Diabetes Mellitus (GDM) at Lusíadas Lisboa Hospital. Inadequate glycemic control in GDM increases the risk of maternal, fetal and neonatal consequences, in this sense, nutritional therapy is essential during the follow-up of these pregnant women. Methods: Cross-sectional observational study. The study sample included 20 pregnant women diagnosed with GDM. Participants were asked to answer a questionnaire that included relevant data and to complete a three-day food record, for which they gave consent. A statistical analysis was performed with IBM® SPSS® 25. Results: The mean age measured was 35±4 years and 75% of the sample were in the 3º trimester. In the pre-gestational period, the sample had a Body Mass Index (BMI) of 26,2±5,3kg/m2 . The mean fasting capillary blood glucose was 89±9mg/dL and the postprandial was 119±19mg/dL. 75% reached the fasting glycemic objective and 95% the postprandial. It was also found that pregnant women who didn´t meet the goal set for fasting blood glucose, had higher pre-gestational BMI. In terms of macronutrients, it was found that 75% of the sample didn´t reach Total Energy Requirements (TER), 50% didn´t reach protein (1,1g/kg of current weight/day and 15-20% TER), 10% lipid (30% TER) and all carbohydrates (50-55% TER), with only 35% reaching the daily minimum of carbohydrates (175g). It was also found that sample didn´t reach 28g/day of fiber. Conclusions: The present study demonstrated the importance of an individualized nutritional intervention by a nutritionist with pregnant women diagnosed with GDM. The importance of this intervention is based on adherence to an adequate dietary pattern that prevents nutritional deficits, enhances clinical outcomes and contributes to the prevention of the incidence of GDM.info:eu-repo/semantics/publishedVersio

Magnetic Glass Ceramics by Sintering of Borosilicate Glass and Inorganic Waste

Ceramics and glass ceramics based on industrial waste have been widely recognized as competitive products for building applications; however, there is a great potential for such materials with novel functionalities. In this paper, we discuss the development of magnetic sintered glass ceramics based on two iron-rich slags, coming from non-ferrous metallurgy and recycled borosilicate glass. The substantial viscous flow of the glass led to dense products for rapid treatments at relatively low temperatures (900–1000 °C), whereas glass/slag interactions resulted in the formation of magnetite crystals, providing ferrimagnetism. Such behavior could be exploited for applying the obtained glass ceramics as induction heating plates, according to preliminary tests (showing the rapid heating of selected samples, even above 200 °C). The chemical durability and safety of the obtained glass ceramics were assessed by both leaching tests and cytotoxicity tests

A study protocol for a randomized controlled trial of an anti-inflammatory nutritional intervention in patients with fibromyalgia

BackgroundThis study aims to analyze the effects of a potentially anti-inflammatory nutritional intervention in disease assessment parameters, inflammatory markers, and quality of life of fibromyalgia (FM) patients.MethodsA sample of 100 female patients diagnosed with FM, followed up at Portuguese Institute of Rheumatology (IPR) in Lisbon, is being randomly allocated in two groups. Patients in the intervention group are adopting an anti-inflammatory diet, characterized by the exemption of the intake of foods containing gluten, dairy, sugar, and ultra-processed foods, during 3months. During the first month, a low fermentable oligo-, di-, and monosaccharides and polyols (FODMAPs) diet is implemented, along with the anti-inflammatory diet, followed by the reintroduction of all fruits and vegetables over a consecutive period of 2months. Patients in the control group are adopting a diet based on general recommendations for healthy eating. The outcomes are pain, fatigue, quality of sleep, quality of life, gastrointestinal symptoms, and inflammation. Before and after the 3months intervention, and also 1month after beginning the intervention, the following questionnaires are applied: Revised Fibromyalgia Impact Questionnaire, visual analog pain scale, Brief Pain Inventory,visual analog scale from a list of common gastrointestinal and extraintestinal symptoms in FM, Short Form 36, Fatigue Severity Survey, and Pittsburg Sleep Quality Index. Ultra-sensitive serum C-reactive protein, eritrocyte sedimentation rate, and interleukin-8 are determined. Age, physical activity, anthropometric parameters, and body composition are being collected. Student's t test will assess the association between the disease evaluation parameters, the inflammatory markers, and the dietary interventions.DiscussionThe results of this study are expected to determine whether a change in patient nutrition helps to alleviate symptoms, which would optimize medical intervention.Trial registrationwww.ClinicalTrials.gov NCT04007705. Registered on July 5, 2019

An anti-inflammatory and low fermentable oligo, di, and monosaccharides and polyols diet improved patient reported outcomes in fibromyalgia: A randomized controlled trial

Background: Fibromyalgia (FM) has been associated with dysbiosis and low-grade inflammation. Studies have reported that diet influences clinical features in FM. Objective: To evaluate the effect of an anti-inflammatory and low fermentable oligo, di, and monosaccharides and polyols (FODMAP) diet on clinical outcomes of patients with FM. Methods: This two arms Randomized Controlled Trial (NCT04007705) included 46 female patients with FM. The intervention group (n = 22) adopted an anti-inflammatory diet for 3 months, excluding gluten, dairy, added sugar, and ultra-processed foods, along with a low FODMAPs diet in the first month. The control group (n = 24) followed general healthy eating recommendations. Both diets were applied by a certified dietitian. Before and after the intervention, participants were assessed regarding pain, fatigue, gastrointestinal symptoms, quality of sleep, and quality of life, through the Revised Fibromyalgia Impact Questionnaire (FIQR), Visual Analogue Pain Scale (VAS), Visual Analog Scale from gastrointestinal symptoms (VAS GI), Brief Pain Inventory (BPI), Pittsburg Sleep Quality Index (PSQI), Fatigue Severity Survey (FSS), and The Short Form Health Survey (SF-36). A blood sample was collected and high-sensitive C-Reactive Protein and Erythrocyte Sedimentation Rate were quantified. Paired Samples t-test/Wilcoxon and independent samples t-test/Mann-Whitney were used to compare variables between groups. Results: After intervention, there was an improvement in intervention group scores of FIQR (p = 0.001), VAS (p = 0.002), BPI (p = 0.011), FSS (p = 0.042), VAS_GI (p = 0.002), PSQI (p = 0.048), and SF36 (p = 0.045) compared to control group. Inflammatory biomarkers (hs-CRP, ESR) did not change in both groups. The intervention was beneficial in the intervention group, regardless of age, disease duration, body mass index variation, and body fat change between baseline and post-intervention. Conclusion: An anti-inflammatory and low-FODMAP diet improved clinical features in patients with FM and may be useful as a complement to pharmacological therapy