Weight Loss Process Research Articles

열경화성 액정 에폭시계 복합재료의 열분해 거동

Liquid crystalline thermosetting epoxy, 4,4'-diglycidyloxy-<TEX>${\alpha}$</TEX>-methylstilbene (DOMS) was synthesized and characterized with cross-polarized optical microscopy (POM) and differential scanning calorimetry (DSC). Carbon nanotube (CNT) or graphene reinforced DOMS composites were fabricated by melt blending with sulfanilamide (SAA) as a curing agent. To investigate the thermal degradation behavior, thermogravimetric analysis (TGA) was performed under nitrogen atmosphere in the temperature range from 30 to <TEX>$1000^{\circ}C$</TEX>. Activation energies for decomposition (Ed) were determined by TGA as a function of the conversion by weight loss processes.

The Struggle Against Fat

Weight loss is an important health issue for overweight girls. Understanding their subjective feelings and experiences regarding weight loss may help healthcare professionals and hospitals develop an appropriate intervention for this population. However, there have been few studies done on the subjective weight loss experiences of overweight adolescent girls. This study developed a descriptive theory framework to elicit the weight loss experiences of overweight adolescent girls in Taiwan. This qualitative study used grounded theory to conduct in-depth interviews with 20 overweight adolescent girls aged 16-20 years. Data were analyzed using the constant comparative method. "Struggle against fat" was the core theme that described and guided the process of weight loss for participants. During this process, "obesity as a stigma" was identified as the antecedent condition with the subcategories: being teased, being blamed, being bullied, and lack of personal attractiveness. Participants struggled to practice a new lifestyle while continuing their previous lifestyle during the weight loss process. This process was categorized as "trying dieting shortcuts," "self-sabotage," "confronting weakness," and "adhere to a new life." During this process, some participants adhered to a new life by perceiving peer/family support, using incentive slogans, and sharing experiences. Finally, participants either continued to maintain their new lifestyle and gradually lost weight or resumed their previous lifestyle and regained weight by entering into a vicious cycle of combating fat through dieting shortcuts while practicing self-sabotage. Weight loss is a difficult issue for most overweight and obese adolescent girls. Health providers should better understand adolescent psychology to provide this population with effective incentives to modify their lifestyles for health purposes. It is crucial that healthcare providers be good coaches to guide and positively support these girls in their struggle against fat.

The effect of movement intervention for women attending courses in weight reduction

Background: Accelerated pace of life and consumerism leads to an increase in obesity. The key element in programs to reduce overweight and obesity is regular physical activity (PA) by means of a healthy lifestyle. Walking, which can be simply assessed by pedometers is appropriate PA that is accessible to everyone, regardless of age and gender. Objective: The aim of our study was to analyse the effect of courses in weight reduction to the selected body composition (BC) parameters in the obese and overweight women of various age and PA level. Methods: 124 women with existing sendenary lifestyles participated in the study, they were differentiated by age (&lt;&#8239;40 years: aged 31.3&#8239;&#177;&#8239;5.4 years, body weight of 88.2&#8239;&#177;&#8239;18.5&#8239;kg, body height of 166.5&#8239;&#177;&#8239;9.5&#8239;cm and &#8805;&#8239;40 years: aged 51.6&#8239;&#177; 7.5 years, body weight of 88.9&#8239;&#177;&#8239;13.3&#8239;kg, body height of 163.8&#8239;&#177;&#8239;8.2&#8239;cm). We divided the monitored sample into sub-groups according to the level of their PA. To determine the average daily number of footsteps during the PA the Yamax pedometer was used. InBody 720 device using the Direct Multi-frequency Bioelectrical Impedance Analysis Method (DSM-BIA Method) was used to measure and analyse the BC. Results: Based on monitoring of PA and BC health risk indicators the effect of the exercise program, which included cognitive behavioural therapy, showed a decline in body mass index (BMI) and body fat expressed in percentages (PBF) and in the decrease of the visceral fat area (VFA). The amount of fat-free mass (FFM) remained the same. Preceding the therapy the BMI average was within the obesity group (BMI&#8239;&gt;&#8239;30&#8239;kg/m2). Following the three month therapy we observed in women with a higher level of PA a shift to the overweight group. Therapy contributed to a reduction in PBF from 2.4% to 3.9% even though the women's groups were still classified as obese (&gt;&#8239;35%). During the repeated measurements significant changes (p&#8239;&lt;&#8239;.05) occurred only in the VFA in relation to different ages. Conclusions: Research studies have shown positive relationships between the increase in PA and changes in health risk indicators. Observance of the recommended number of 10,000 footsteps per day primarily prevents the increase in body fat mass (BFM) and maintains FFM. Taking up a weight reduction program is essential when commencing the weight loss process in the course of lifestyle change.

Leucine: Considerations about the Effects of Supplementation

The main objective of this study is the considerations about the Effects of Leucine Supplementation. Leucine is a branched chain amino acids (BCAA), which is characterized by the ability to be formed from a conformation where an R grouping is non-polar aliphatic. It is noticeable a steady increase in the use of nutritional supplements among physically active, justifying the need of studies to verify the possible benefits and risks that they may lead to health of individuals. In this aspect, this study aimed to highlight the main biochemical and functional characteristics of Leucine. In addition to analyze the possible effects of its supplementation in diets for weight loss on physical performance as well as its benefits to human health, with the largest number of studies that addressed the issue, both in humans and in animals. According to the bibliography found, the Leucine supplementation can influence the protein synthesis, thus contributing to the anabolism, in addition to having an important role in regulating glucose homeostasis aiding weight loss process. Leucine appears as an important supplement for health benefits as an adjunct in the treatment of insulin resistance and may assist in gaining muscle mass in the elderly, as well as contributing to recovery from injuries and wounds in the muscle tissue. It is still necessary more research into the potential health benefits in view that many of the articles analyzed were conducted in animals. It is noteworthy that most of the research conducted tests on animals, highlighting the importance of greater academic literature on this topic. Besides, most relevant studies to conclusions about the effect of intake of leucine in physical performance are also needed, as there are still many disagreements over the results of leucine supplementation on this aspect.

Influence of Na&lt;sub&gt;2&lt;/sub&gt;CO&lt;sub&gt;3&lt;/sub&gt; on Thermal Decomposition of Waste Printed Circuit Board in Carbon Dioxide

The influence of Na2CO3on RF4-type waste printed circuit board (PCB) pyrolysis in carbon dioxide was studied with thermogravimetric analysis, and the reaction kinetics was calculated based on the Coats - Redfern method. It is shown that the weight loss process of waste PCB in carbon dioxide includes two stages. The first stage of weight loss is between 280 °C and 450 °C, at which the decomposition of epoxide resin leads to volatile materials release. The second stage of weight loss is the reaction between carbon residue and carbon dioxide between 600°C~960 °C, and carbon monoxide is formed. Addition of Na2CO3decreases the initial temperature of the second weight loss stage of waste PCB and increases the weight loss rate, which indicates the enhancement effect on gasification reaction between carbon residue and carbon dioxide. From the different mechanism function, the optimal mechanism function isf(a)=5(1-a)/4[-ln(1-a)]4and the range of activation energy is 75～135 kJ/mol.

Pharmacokinetics of Drugs in Cachectic Patients: A Systematic Review

Cachexia is a weight-loss process caused by an underlying chronic disease such as cancer, chronic heart failure, chronic obstructive pulmonary disease, or rheumatoid arthritis. It leads to changes in body structure and function that may influence the pharmacokinetics of drugs. Changes in gut function and decreased subcutaneous tissue may influence the absorption of orally and transdermally applied drugs. Altered body composition and plasma protein concentration may affect drug distribution. Changes in the expression and function of metabolic enzymes could influence the metabolism of drugs, and their renal excretion could be affected by possible reduction in kidney function. Because no general guidelines exist for drug dose adjustments in cachectic patients, we conducted a systematic search to identify articles that investigated the pharmacokinetics of drugs in cachectic patients.

Decomposition kinetic characteristics of calcium carbonate containing organic acids by TGA

By means of thermogravimetric analysis (TGA), influences of organic acids such as citric acid, oxalic acid and tartaric acid on decomposition process and thermal behaviors of calcium carbonate were investigated in non-isothermal condition. Experiments were conducted from the ambient temperature to 1273K at a heating rate of 10Kmin−1. Moreover, the kinetic parameters (activation energy and pre-exponential factor) of the mixtures of calcium carbonate and organic acids were determined using the Coats–Redfern method. It is indicated that the decomposition process of calcium carbonate containing different organic acids includes three or four weight loss processes. In the zone of 370–450°C, energy is released due to the combustion of organic products decomposed from organic salts, and energy increases with the increase of molecular weight of organic acid. Activation energy of the samples containing citric acid, oxalic acid and tartaric acid is decreased by 34.9%, 28.8% and 31.9%, respectively. The results may be used to provide a useful basis for further applying industrial wastes containing different organic acids in cement industries with high-efficiency.

The Preparation of Aramid Paper and its Properties

The meta-aramid fibrids were prepared by precipitation in this paper. The meta-aramid solution dissolved in the solvent system DMAc/LiCl was injected into the high shearing coagulant at room temperature and the mixture of water and N, N-dimethylacetamide(DMAc) was used as coagulant. The shearing rate, viscosity of the solution and the concentration of water in coagulant were the main factors on effecting the formation of fibrids. The meta-aramid fibrid has a gradual weight loss process when the temperature increases from 100°C to 400°C, lower thermal property of meta-aramid fibrid was due to the hydrogen bonding and crystalline structure were broken during dissolving process, however, a flexible and easy dispersing property of meta-aramid fibrid in fluid is due to its amorphous structure, which are very important that the meta-aramid fibrid has a better binding and adhesive property with the aramid short fiber in aramid paper, then yield a high mechanical and insulation property for aramid paper. Then, the properies of aramid paper were investigated. The results indicated that the proportion of meta-aramid fibrid in the aramid paper and the length of shorten aramid fiber are the main factors for affecting the strength and the other properties of aramid paper.

Experimental and First‐Principles Characterization of Functionalized Magnetic Nanoparticles

Magnetic iron oxide nanoparticles synthesized by coprecipitation and thermal decomposition yield largely monodisperse size distributions. The diameters of the coprecipitated particles measured by X-ray diffraction and transmission electron microscopy are between approximately 9 and 15 nm, whereas the diameters of thermally decomposed particles are in the range of 8 to 10 nm. Coprecipitated particles are indexed as magnetite-rich and thermally decomposed particles as maghemite-rich; however, both methods produce a mixture of magnetite and maghemite. Fourier transform IR spectra reveal that the nanoparticles are coated with at least two layers of oleic acid (OA) surfactant. The inner layer is postulated to be chemically adsorbed on the nanoparticle surface whereas the rest of the OA is physically adsorbed, as indicated by carboxyl O-H stretching modes above 3400 cm(-1). Differential thermal analysis (DTA) results indicate a double-stepped weight loss process, the lower-temperature step of which is assigned to condensation due to physically adsorbed or low-energy bonded OA moieties. Density functional calculations of Fe-O clusters, the inverse spinel cell, and isolated OA, as well as OA in bidentate linkage with ferrous and ferric atoms, suggest that the higher-temperature DTA stage could be further broken down into two regions: one in which condensation is due ferrous/ferrous- and/or ferrous/ferric-OA and the other due to condensation from ferrous/ferric- and ferric/ferric-OA complexes. The latter appear to form bonds with the OA carbonyl group of energy up to fivefold that of the bond formed by the ferrous/ferrous pairs. Molecular orbital populations indicate that such increased stability of the ferric/ferric pair is due to the contribution of the low-lying Fe(3+) t(2g) states into four bonding orbitals between -0.623 and -0.410 a.u.

The Pyrolysis Characteristics of Low Ash Lignite

The pyrolysis characteristics of lignite with low ash were investigated and the influences of heating rate on the weight loss process were also discussed. The results showed the lignite pyrolysis process can be divided into three stages, in which the second stage, the temperature range is about 300oC ~550oC, is the main process of the weight loss; with the heating rate is enhanced, the temperature of maximum rate of weight loss was increased while the maximum rate of coal weight loss is increased, and the temperature of maximum rate of coal weight loss is basically the same.

Shifting processes model: A conceptual model for sustainable weight management.

Weight-loss maintenance is widely accepted to be a difficult and often elusive process. The transtheoretical model (TTM) provides a useful description of five stages of change. Applied to weight management, weight loss occurs during the action stage and weight-loss maintenance occurs during the maintenance stage. Despite its broad utility, the TTM does not adequately explain the complexity involved with a shift from action to maintenance. Based on Engel's (G. L. Engel, 1977, The need for a new medical model: A challenge for biomedicine, Science, Vol. 196, pp. 129-136) biopsychosocial model and family systems theory, a shifting processes model is proposed to describe the potential differences and shift that occurs between weight loss and weight-loss maintenance processes within relational contexts.

An ounce of time, a pound of responsibilities and a ton of weight to lose: An autoethnographic journey of barriers, message adherence and the weight-loss process

This article uses an autoethnographic approach to determine how the intersectionality of identities affects message perceptions about weight loss from the lens of two doctoral students. This autoethnography links our personal experiences with the societal and cultural phenomena of obesity and weight loss, and the rhetoric of messages. We know there is a gap in public relations literature about autoethnography, health communication and intersectionality, and we hope to fill it. We also know health communicators seek more effective ways to reach an increasingly diverse audience; we hope to shed light on the issue. We know that many women want to lose weight and hope our narratives will resonate with them. Finally, we recognize autoethnographic skeptics exist in academia, and we hope our article provides insight into and understanding of the usefulness of autoethnographies in the field of public relations.

Mechanical properties, morphology and thermal degradation of a biocomposite of polypropylene and curaua fibers: coupling agent effect.

Biocomposites of polymers with vegetal fibers have a broad spectrum of applications due to their high specific properties in comparison to their counterparts made with fiberglass. Polypropylene, PP, composites with curaua fiber compatibilized with different concentrations of maleic anhydride grafted polypropylene, PP-g-MA, were characterized according to their mechanical properties, morphologies and thermal stabilities in oxidative and inert atmospheres. The composites were prepared by single screw extrusion and injection molded specimens were used for testing. The composite with 20 wt % of curaua fiber with and without compatibilizer presented improved mechanical properties compared to pure PP. The use of PP-g-MA as a compatibilizer significantly increased fiber/matrix adhesion, however, the mechanical properties were only slightly improved in comparison with composites without compatibilizer. We observed an improvement in thermal stability of the composites, compared to that expected from the weighted average of the individual components, both under inert and oxidative atmospheres. Furthermore, the thermal stability improved under inert atmosphere as a function of the concentration of compatibilizer. In this situation, indeed, there was a different shift of the weight loss processes owing to the presence of the compatibilizer.

Addressing weight loss recidivism: a clinical focus on metabolic rate and the psychological aspects of obesity.

Obesity in the United States has reached epidemic proportions and has become an unprecedented public health burden. This paper returns to the evidence for metabolic rate set points and emphasizes the clinical importance of addressing changes in metabolic rate throughout the weight loss process. In addition to the importance of clinically attending to the modulation of metabolic rate, the psychological aspects of obesity are addressed as part of the need to holistically treat obesity.

Obesity and Treatment Meanings in Bariatric Surgery Candidates: A Qualitative Study

This study used a qualitative approach to comprehend how the morbid obese conceptualize and deal with obesity and obesity treatment, with the particular aim of exploring the expectations and beliefs about the exigencies and the impact of bariatric surgery. The study population included 30 morbid obese patients (20 women and 10 men) with a mean age of 39.17 years (SD = 8.81) and a mean body mass index of 47.5 (SD = 8.2) (reviewer #2, comment #9) interviewed individually before surgery using open-ended questions. The interviews were audiotaped, transcribed, and then coded according to grounded analysis methodology. Three main thematic areas emerged from the data: obesity, eating behavior, and treatment. Obesity is described as a stable and hereditary trait. Although participants recognize that personal eating behavior exacerbates this condition, patients see their eating behavior as difficult to change and control. Food seems to be an ever-present dimension and a coping strategy, and to follow an adequate diet plan is described as a huge sacrifice. Bariatric surgery emerges as the only treatment for obesity, and participants highlight this moment as the beginning of a new life where health professionals have the main role. Bariatric surgery candidates see their eating behavior as out of their control, and to commit to its demands is seen as a big sacrifice. For these patients, surgery is understood as a miracle moment that will change their lives without requiring an active role or their participation. According to these results, it is necessary to validate them with qualitative and quantitative studies (reviewer #2, comment #3); it is necessary to promote a new awareness of the weight loss process and to empower patients before and after bariatric surgery.

Cavitation Erosion on Solid Polymers of Polytetrafluoroethelyene

A 100-h-long cavitation erosion experiment was performed on a sample of polytetrafluoroethelyene (PTFE). The weight loss curve of PTFE was different from that of metals, and the erosion process was characterized by two stages, each with a distinct erosion rate. Morphology studies on the erosion pits and X-ray diffraction analysis of the eroded surfaces revealed that brittle fracture was the main reason for the higher erosion rate at the beginning of the erosion process, while ductile fracture dominated the weight loss process later in the erosion process, thereby reducing the erosion rate. Based on these results, we consider that this transition from brittle to ductile fracture was responsible for the different erosion rates at the two different erosion stages.

Satisfaction and Quality-of-Life Issues in Body Contouring Surgery Patients: a Qualitative Study

Body contouring, which encompasses a range of surgical procedures on different areas of the body, is one of the most rapidly growing areas of plastic surgery. Little is known about outcomes from the perspective of post-weight loss body contouring patients. The aim of our qualitative study was to identify the health and aesthetic concerns of such patients through in-depth patient interviews. Forty-three bariatric surgery post-weight loss body contouring patients were recruited between September 2009 and January 2011 from the offices of five plastic surgeons located in the USA and Canada. Interviews were used to explore the impact that obesity, weight loss, and body contouring surgery had on all aspects of the patient's life. Interviews were transcribed and data analysis involved coding and the use of the constant comparison method to develop categories and themes. Interviewing continued until no new themes emerged. Patients described a range of important health and aesthetic concerns related to body contouring surgery following massive weight loss, including the following: appearance-related concerns, physical health concerns, sexual health concerns, psychological health concerns, and social health concerns. Body contouring surgery played an instrumental role in the completion of the entire weight loss process for patients. The removal of excess skin leads to improvements in a patient's appearance and enhanced physical, psychological, and social health and well-being. In order to appropriately measure the impact of body contouring procedures from the patient's perspective, a well-developed psychometrically sound patient-reported outcome instrument is needed.

Weight loss in combat sports: physiological, psychological and performance effects

BackgroundThe present article briefly reviews the weight loss processes in combat sports. We aimed to discuss the most relevant aspects of rapid weight loss (RWL) in combat sports.MethodsThis review was performed in the databases MedLine, Lilacs, PubMed and SciELO, and organized into sub-topics: (1) prevalence, magnitude and procedures, (2) psychological, physiological and performance effects, (3) possible strategies to avoid decreased performance (4) organizational strategies to avoid such practices.ResultsThere was a high prevalence (50%) of RWL, regardless the specific combat discipline. Methods used are harmful to performance and health, such as laxatives, diuretics, use of plastic or rubber suits, and sauna. RWL affects physical and cognitive capacities, and may increase the risk of death.ConclusionRecommendations during different training phases, educational and organizational approaches are presented to deal with or to avoid RWL.

Weight management issues and strategies for people with high cardiovascular risk undertaking an Australian weight loss program: A focus group study

Obesity is particularly hazardous for people with multiple cardiovascular risk factors and existing cardiovascular disease, although few studies investigate experiences and perceptions of weight loss in this population. This study provides an understanding of participants' knowledge, attitudes, and experiences of managing multiple risk factors and/or existing cardiovascular disease of participants who were undertaking a weight loss program. Thirty-five participants were recruited from the first 50 completing a multicomponent group-based weight loss intervention designed to follow cardiovascular disease and diabetes disease management programs. Four focus group interviews were conducted using a semistructured interview schedule. Data were analyzed using an inductive approach, and themes developed. Participants found the process of weight loss to be complex, dynamic, and challenging, as the conflicting needs of existing health conditions, social support, ambivalence, and time limitations required careful balance. In response, participants determinedly developed and tested strategies based on simplified principles, establishing routines for new health habits and portion control, and going back to basics in food selection. Therefore, weight loss programs for this population need to be specifically tailored to support patients' efforts and strategies.

Protic Ionic Liquids Based on a Super-Strong Base: Correlation between Physicochemical Properties and ΔpKa

ABSTRACT1,8-Diazabicyclo[5,4,0]undec-7-ene (DBU) was neutralized by a range of Brønsted acids with a wide variation in the ΔpKa values of their constituent acids and base. The salts exhibited properties characteristic of an ionic liquid, such as high thermal stability and liquidity near ambient temperature. Analyses of thermal behaviors and temperature dependencies of density, viscosity (η), and ionic conductivity were made to correlate the physicochemical properties with the ΔpKa value of the obtained protic ionic liquids (PILs). Differential thermal analyses (DTA) revealed that PILs with high ΔpKa values underwent thermal decomposition resembling their aprotic counterparts; however, PILs with a low ΔpKa exhibited the evaporation of neutral species progressively generated from the shifting of the equilibrium toward neutral components during the weight loss process. The ionicity of the PILs, determined from Walden plots utilizing density, conductivity, and viscosity data, was found to decrease as temperature increased, and this effect was more pronounced for low ΔpKa values, possibly because of the shifting of the equilibrium and the imbalance between strong hydrogen bonds and Coulombic interactions. Fragility, estimated from plots of log(η) versus the scaled temperature Tg/T was found to be lower for PILs than for DBU owing to neutralization. [DBU]-based PILs exhibit intermediate fragility in nature, but this fragility becomes more prominent for PILs with low ΔpKa values