Upgrading and Enhancement of Recycled Polyethylene Terephthalate with Chain Extenders: In-Depth Material Characterization.

Chemical chain extenders (CEs) can be used to restore the properties of recycled low-molecular-weight polyethylene terephthalate (PET). The aim of this work is to investigate the influence of the type and concentration of the CEs Joncryl and pyromellitic dianhydride (PMDA) on the viscosity and other rheological properties with a unique combination of different methods based on industrial samples originating from recycled PET bottles and trays. The resulting chain-extended thermoplastics were characterized by a combination of differential scanning calorimetry, viscometry, cone plate rheometry, pyrolysis-gas chromatography-mass spectroscopy, optical photothermal infrared spectroscopy, 13C solid-state- and 1H NMR liquid spectroscopy, and size exclusion chromatography. For a recycled PET mixture containing bottle and tray materials, our investigations have shown that a significantly better effect for chain elongation can be achieved with Joncryl compared to PMDA. This can presumably be attributed to water molecules formed during the use of PMDA, which accelerate the degradation of PET. The storage modulus values are therefore significantly higher for the samples with Joncryl compared to PMDA. The results of this study show that chain extension with Joncryl proceeds better compared to the reaction with PMDA.

Reducing plastic pollution caused by demersal fisheries.

Marine microplastics generated by wear and tear of bottom trawls and demersal seines during their service life is a growing environmental concern that requires immediate attention. In Norway, these fishing gears account for more than 70 % of the landings of demersal fish species, but they are also the leading sources of microplastics generated by fisheries. Because these two fishing gears are widely used around the world, replacing fossil-based non-degradable plastics with more abrasion-resistant materials, including biodegradable polymers, should contribute to the reduction of marine litter and its associated environmental impacts. However, the lack of available recycling techniques and the need for separate collection of biodegradable polymers means that these materials will most likely be incinerated for energy recovery, which is not favourable from a circular economy perspective. Nonetheless, from an environmental perspective the use of such biodegradable polymers in demersal fisheries could still be a better alternative to standard polymer materials.

Enhanced Impact Strength of Recycled PET/Glass Fiber Composites.

In this paper, we report a study on the effects of different ethylene copolymers in improving the impact strength of a fiber-reinforced composite based on a recycled poly(ethylene terephthalate) (rPET) from post-consumer bottles. Different ethylene copolymers have been selected in order to evaluate the effects of the polar co-monomer chemical structure and content. The composite mixtures were prepared via melt extrusion, and the samples were manufactured by injection molding. Impact strength was evaluated using Izod tests, and a morphological study (FESEM) was performed. As a result, a composite with substantially improved impact properties was designed. This study demonstrates that a post-consumer PET from the municipal waste collection of plastic bottles can be successfully used as a matrix of high-performance, injection-molded composites, suitable for use in the automotive sector, among others, with no compromise in terms of mechanical requirements or thermal stability.

Above cuff vocalisation (ACV): A scoping review.

INTRODUCTION: Patients in intensive care frequently suffer from not being able to communicate verbally. The aim of this scoping review was to study the safety and effectiveness of the above cuff vocalisation (ACV) on speech and quality of life (QOL) in patients dependent on a cuffed tracheostomy. METHODS: A scoping review was conducted. The databases Ovid Medline, Cochrane Library, and Embase were systematically searched in May 2020. We included clinical studies with patients exposed to ACV where speech, QOL or safety issues were assessed. RESULTS: Overall, 17 studies were included, of which 15 were observational and 2 were randomised controlled trials. Totally, 231 patients were included. ACV enabled most of the included patients (115/131; 88%) to speak with an audible voice or whisper (moderate quality of evidence). Voice related QOL (V-RQOL) and QOL in mechanically ventilated patients (QOL-MV) improved from pre- to post- ACV compared to a control group not tolerating a one-way speaking valve (P = .01 and P = .04, respectively) (very low quality of evidence). Several minor complications or problems were reported in 20/75 (27%) cases in addition to two serious adverse events: subcutaneous emphysema in one patient where the tracheostomy was dislodged and a distended trachea in another due to the misconnection of continuous gas to the cuff (low/ very low quality of evidence). CONCLUSION: ACV facilitated communication in patients dependent on a cuffed tracheostomy and attempting to communicate. Quality of evidence in improved V-RQOL and QOL-MV was very low. Several minor complications and two serious adverse events were reported.

Quality of Life After Breast Enlargement With Implants Versus Augmentation Mastopexy: A Comparative Study.

BACKGROUND: Research regarding quality of life (QoL) among women who have undergone breast aesthetic surgery is expanding. A comparative, anonymous study between the two main breast aesthetic procedures is needed. OBJECTIVES: The authors compared patient characteristics and aspects of QoL among women who underwent breast enlargement with implants (BI group) and those who underwent augmentation mastopexy (AM group). METHODS: Patients at the Oslo Plastic Surgery Clinic were given a 47-question survey to measure QoL. The survey was anonymous; 61 patients who received breast implants and 37 patients who underwent augmentation mastopexy between 2005 and 2009 responded. Answers were processed by a QuestBack return mail system and sent to the authors. Statistical analyses were performed to evaluate significance between the groups. RESULTS: The response rate was 67% in the BI group and 88% in the AM group. Mean follow-up time was 2.8 years in both groups. Motivation for surgery was primarily cosmetic (65%) and emotional (48%) in the BI group as well as cosmetic (78%) and physical (31%) in the AM group. The effects on psychosocial aspects were significant in the BI group regarding life changes and feeling like a "whole" person (68.9% vs 40.5% and 73.8% vs 40%). BI group also had a significantly higher satisfaction with overall cosmetic result, enlargement, and breast volume (93.4 %, 90.2%, 80% vs 69.4%, 70.2% vs 67% in AM group). Additionally, the BI group was more satisfied with shape, scar, and symmetry (90.1% vs 63.9%, 70.6% vs 40.5%, and 83.6% vs 54.0%, respectively). CONCLUSIONS: None of our patient groups were stereotypical and motivation for surgery was primarily cosmetic in both groups. BI patients were significantly more satisfied with the aesthetic outcome and the QoL of many psychosocial aspects. AM patients may have had different expectations than BI patients and a significant dissatisfaction was reported in shape, scarring, symmetry, and the nipple-areola complex.

Cognitive Event-Related Potentials during the Sub-Acute Phase of Severe Traumatic Brain Injury and Their Relationship to Outcome.

Predicting outcome in the early phase after severe traumatic brain injury (sTBI) is a major clinical challenge, particularly identifying patients with potential for good cognitive outcome. The current single-center prospective study aimed to explore presence and normalization of electroencephalography (EEG)-based event-related potentials (ERPs) in the early phase followings TBI, and their relationship to functional and cognitive outcome 6 months post-injury. Fourteen adult patients (eight males) with sTBI were recruited from the neurointensive care unit (mean age = 38.2 years [standard deviation (SD) = 14.7]; mean lowest Glasgow Coma Scale (GCS) score within first 24 h = 5.4, SD = 1.87). EEG recordings were conducted biweekly at three time-points applying an ERP paradigm encompassing a passive condition involving hearing their own name randomly interspersed between an unfamiliar name (UN), and an active condition with instruction to count their own name. Functional and cognitive outcome 6 months post-injury was measured with Glasgow Outcome Scale-Extended (GOSE) and neuropsychological tests of attention and memory. Ten patients demonstrated a significantly enhanced cognitive P3 in the active counting task compared with passive listening across recordings, and six presented with normalization of P3 in the counting task. Moreover, P3 amplitude to the counting task at the third time-point was positively correlated with both functional outcome (GOSE) and cognition (verbal learning, attentional set-shifting, and switching) 6 months post-injury. ERP can index cognitive capacities in the early phase following sTBI, and the cognitive P3 component in an active design is associated with functional and cognitive outcome, demonstrating that the cognitive P3 may yield valuable information of residual cognition and provide supplementary prognostic information.

Gastrobronchial fistula following minimally invasive esophagectomy for esophageal cancer in a patient with myotonic dystrophy: Case report.

INTRODUCTION: Myotonic dystrophies are inherited multisystemic diseases characterized by musculopathy, cardiac arrythmias and cognitive disorders. These patients are at increased risk for fatal post-surgical complications from pulmonary hypoventilation. We present a case with myotonic dystrophy and esophageal cancer who had a minimally invasive esophagectomy complicated with gastrobronchial fistulisation. PRESENTATION OF CASE: A 44-year-old male with myotonic dystrophy type 1 and esophageal cancer had a minimally invasive esophagectomy performed instead of open surgery in order to reduce the risk for pulmonary complications. At day 15 respiratory failure occurred from a gastrobronchial fistula between the right intermediary bronchus (defect 7-8mm) and the esophagogastric anastomosis (defect 10mm). In order to minimize large leakage of air into the gastric conduit the anastomosis was stented and ventilation maintained at low airway pressures. His general condition improved and allowed extubation at day 29 and stent removal at day 35. Bronchoscopy confirmed that the fistula was healed. The patient was discharged from hospital at day 37 without further complications. DISCUSSION: The fistula was probably caused by bronchial necrosis from thermal injury during close dissection using the Ligasure instrument. Fistula treatment by non-surgical intervention was considered safer than surgery which could be followed by potentially life-threatening respiratory complications. Indications for stenting of gastrobronchial fistulas will be discussed. CONCLUSIONS: Minimally invasive esophagectomy was performed instead of open surgery in a myotonic dystrophy patient as these patients are particularly vulnerable to respiratory complications. Gastrobronchial fistula, a major complication, was safely treated by stenting and low airway pressure ventilation.

Survey of breast implant patients: characteristics, depression rate, and quality of life.

BACKGROUND: Quality of life (QOL) among breast augmentation patients is a growing research area, with newly worrisome data on psychological health in this group. OBJECTIVES: The authors investigate characteristics of breast implant patients, including motivations for surgery, depression rate, effect of surgery on daily activity and work activity, and overall psychosocial and cosmetic changes through a self-reported survey. METHODS: Of 121 consecutive breast augmentation patients treated by the senior author (AK) between 2005 and 2008, a total of 93 patients were reachable via e-mail and were sent a 47-question survey, which they could return anonymously. Answers were processed by QuestBack mail system (QuestBack AS, Oslo, Norway) and sent to the authors as diagrams and figures, rather than as raw data. RESULTS: The response rate for this survey was 67%. Average follow-up was 2.8 years. For 65%, the motivation for surgery was cosmetic; 48% replied it was for emotional reasons (reduced self-esteem), 22% for intimate reasons, and 10% for physical reasons. Before the operation, 6% of respondents reported diagnosed depression. The postoperative changes were equal between improved and worsened depression. In 27%, the operation increased motivation for daily activities; 73% felt like a "whole" person, and 26% experienced improvement in social skills. In terms of the cosmetic result, 93% were satisfied or very satisfied. However, 27% indicated they were unsatisfied or very unsatisfied with skin sensation. CONCLUSIONS: Although in some cases depression increased postoperatively, the depression rate in our study was still lower than the published range in the general population in Norway. Breast enlargement increased motivation to perform daily activities in our patients. The procedure improved QOL in both psychosocial and cosmetic aspects. However, the relatively high percentage of patients who experienced reduced breast skin sensitivity postoperatively can represent a challenge for the surgeon. Multicenter/clinic studies are necessary to form a better idea about the implications of the depression rate postoperatively.

Does an early onset and continuous chain of rehabilitation improve the long-term functional outcome of patients with severe traumatic brain injury?

There are currently no international guidelines regarding treatment in the early rehabilitation phase for persons with severe traumatic brain injury (TBI), and only a few studies have investigated the effect of integrating rehabilitation into acute TBI care. The aim of the study was to evaluate whether a continuous chain of rehabilitation that begins with the acute phase could improve the functional outcome of severe TBI patients, compared to a broken chain of rehabilitation that starts in the sub-acute phase of TBI. A total of 61 surviving patients with severe TBI were included in a quasi-experimental study conducted at the Level I trauma center in Eastern Norway. In the study, 31 patients were in the early rehabilitation group (Group A) and 30 patients were in the delayed rehabilitation group (Group B). The functional outcomes were assessed 12 months post-injury with the Glasgow Outcome Scale Extended (GOSE) and the Disability Rating Scale (DRS). A favorable outcome (GOSE 6-8) occurred in 71% of the patients from Group A versus 37% in Group B (p=0.007). The DRS score was significantly better in Group A (p=0.03). The ordinal logistic regression analysis was used to quantify the relationship between the type of rehabilitation chain and the GOSE. A better GOSE outcome was found in patients from Group A (unadjusted OR 3.25 and adjusted OR 2.78, respectively). These results support the hypothesis that better functional outcome occurs in patients who receive early onset and a continuous chain of rehabilitation.

Oxidative and nonoxidative glucose disposal in elderly vs younger men with similar and smaller body mass indices and waist circumferences.

Defects in oxidative and nonoxidative glucose metabolism may be involved in the insulin resistance of aging, possibly linked to a central redistribution of body fat. By hyperinsulinemic-euglycemic clamps with whole-body indirect calorimetry, we assessed the contributions of oxidative and nonoxidative glucose disposal to insulin action in 12 elderly persons and 2 groups of younger subjects (14 in each) who had participated in a large population study. Subjects from Young-1 were individually matched to the elderly persons by body mass index and had similar waist circumferences, whereas subjects from Young-2 had a body mass index typical of their age group in the population study and smaller waist measurements. In the combined sample, we also considered possible determinants, related to age and central fat, of flux through these metabolic pathways. The elderly persons had lower nonoxidative glucose disposal compared with the men in Young-2 ( P = .0450 by analysis of variance), whereas glucose oxidation did not differ between the groups. Glucose oxidation correlated negatively with waist circumferences, triglycerides, and alanine aminotransferase and positively with total testosterone and sex hormone-binding globulin. Nonoxidative glucose metabolism correlated inversely with waist circumferences, triglycerides, and free fatty acids and positively with maximum O 2 consumption and total testosterone. In the best regression models, alanine aminotransferase and triglycerides were negatively associated with glucose oxidation (model R 2 = 39%), whereas lower baseline free fatty acids and higher maximum O 2 consumption and sex hormone-binding globulin predicted enhanced nonoxidative glucose metabolism (model R 2 = 47%). These results substantiate that measures to avert abdominal adiposity may prevent insulin resistance and its related metabolic derangements in elderly persons.

Age or waist as determinant of insulin action?

Several studies have shown that insulin action deteriorates with age, possibly mediated through accumulation of abdominal fat. We determined peripheral insulin action in elderly and younger men who had participated in a large population study (the Tromsø Study). To 15 elderly participants aged 71 to 77 years, we individually matched 15 younger participants aged 31 to 33 years (Y1) by body mass index (BMI). A second young group (Y2) comprised 15 participants also aged 31 to 33 years, but with BMI representative of this age group in the population study. All underwent hyperinsulinemic euglycemic clamps (0.4 mU/kg/min), oral glucose tolerance tests, and determinations of Vo2max. Insulin sensitivity index (ISI=glucose disposal per kg fat-free mass [FFM] divided by steady-state insulin concentration) did not differ between the elderly and Y1, but was higher in Y2 (0.10+/-0.01, 0.12+/-0.01, and 0.17+/-0.02, P=.0011 by analysis of variance [ANOVA]). Adjustment by waist circumferences (analysis of covariance [ANCOVA]) abolished this difference. In univariate analysis of pooled data, ISI correlated negatively to body fat indices, serum triglycerides, and free fatty acids (FFA), and positively to Vo2max. In multiple regression analysis, waist circumference and triglycerides were the only independent predictors of insulin sensitivity, whereas age had no impact. The results confirm that the decline in insulin action seen in elderly people is related to increased abdominal fat rather than aging per se.