Climate footprint assessment of plastic waste pyrolysis and impacts on the Danish waste management system.

Increased plastic recycling is necessary to reduce environmental impacts related to manufacturing and end-of-life of plastic products, however, mechanical recycling (MR) - currently the most widespread recycling option for plastic waste - is limited by quality requirements for inputs and reduced quality of outputs. In this study, pyrolysis of plastic waste is assessed against MR, municipal solid waste incineration (MSWI) and fuel substitution through climate footprint assessment (CFA) based on primary data from pyrolysis of plastic waste sourced from Danish waste producers. Results of the CFA are scaled to the Danish plastic waste resource in an impact assessment of current Danish plastic waste management, and scenarios are constructed to assess reductions through utilization of pyrolysis. Results of the CFA show highest benefits utilizing pyrolysis for monomer recovery (-1400 and -4800 kg CO2e per ton polystyrene (PS) and polymethyl methacrylate (PMMA), respectively) and MR for single polymer polyolefins (-1000 kg CO2e per ton PE). The two management options perform similarly with mixed plastic waste (200 kg CO2e per ton plastic waste). MSWI has the highest impact (1600-2200 kg CO2e per ton plastic waste) and should be avoided when alternatives are available. Scaling the results of the CFA to the full Danish plastic waste resource reveals an impact of 0.79 Mt CO2e in year 2020 of current plastic waste management. Utilizing pyrolysis to manage MR residues reduces the system impact by 15%. Greater reductions are possible through increased separation of plastic from residual waste. The best performance is achieved through a combination of MR and pyrolysis.

Successful weight loss initiation and maintenance among adolescents with overweight and obesity: does age matter?

Treatments for adolescents with overweight/obesity demonstrate mixed success, which may be due to a lack of consideration for developmental changes during this period. Potential developmental differences in weight loss motivations, weight maintenance behaviours and the role of parents in these efforts were examined in a sample of successful adolescent weight losers. Participants enrolled in the Adolescent Weight Control Registry (n = 49) self-reported demographic information and weight history, reasons for weight loss and weight control, weight loss approach and weight maintenance strategies, and perceived parental involvement with weight loss. Associations between age at weight loss initiation and the aforementioned factors were examined using linear and generalized regressions, controlling for highest z-BMI and sex. Adolescents who were older (≥16 years) at their weight loss initiation were more likely to report losing weight on their own (37.5% vs. 75%, P = 0.01) and reported greater responsibility for their weight loss and weight loss maintenance (P < 0.001) compared to younger adolescents. Younger age at weight loss initiation was associated with greater parental involvement (P = 0.005), whereas older age was associated with greater adolescent responsibility for the decision to lose weight (P = 0.002), the weight loss approach (P = 0.007) and food choices (P < 0.001). Findings suggest the importance of considering developmental differences in responsibility for weight loss and maintenance among adolescents with overweight/obesity.

Return to theatre following total hip and knee replacement, before and after the introduction of rivaroxaban: a retrospective cohort study.

Rivaroxaban has been recommended for routine use as a thromboprophylactic agent in patients undergoing lower-limb arthroplasty. However, trials supporting its use have not fully evaluated the risks of wound complications. This study of 1048 total hip/knee replacements records the rates of return to theatre and infection before and after the change from a low molecular weight heparin (tinzaparin) to rivaroxaban as the agent of chemical thromboprophylaxis in patients undergoing lower-limb arthroplasty. During a period of 13 months, 489 consecutive patients undergoing lower-limb arthroplasty received tinzaparin and the next 559 consecutive patients received rivaroxaban as thromboprophylaxis. Nine patients in the control (tinzaparin) group (1.8%, 95% confidence interval 0.9 to 3.5) returned to theatre with wound complications within 30 days, compared with 22 patients in the rivaroxaban group (3.94%, 95% confidence interval 2.6 to 5.9). This increase was statistically significant (p = 0.046). The proportion of patients who returned to theatre and became infected remained similar (p = 0.10). Our study demonstrates the need for further randomised controlled clinical trials to be conducted to assess the safety and efficacy of rivaroxaban in clinical practice, focusing on the surgical complications as well as the potential prevention of venous thromboembolism.

Day-case laparoscopic Nissen fundoplication.

INTRODUCTION: Nissen fundoplication has been performed laparoscopically for over 15 years, being associated with shorter hospital stay and fewer complications than conventional open surgery with good long-term outcomes. Day-case laparoscopic Nissen fundoplication (LNF) is rarely performed in the UK and most series in the literature report length of stay >2 days. METHODS: The objective of this study was to examine the safety and efficacy of day-case LNF. The clinical records of all patients undergoing LNF under the care of three surgeons in a district general hospital (DGH) during a 5-year period (January 2003 to December 2007) were reviewed to examine length of stay, complications, length of procedure, grade of operating surgeon and symptoms on follow-up. RESULTS: One hundred thirteen day-case LNFs were recorded in this series. Day-case LNF patients had median age of 45 years (range 20-68 years, 65% (64.6%) male) and 98% were American Society of Anesthesiologists (ASA) grade I or II. Twenty-one cases (19%) were performed by higher surgical trainees. Median operative time was 54 minutes (range 25-120 min). Only one perioperative complication (port-site bleed) occurred, treated without prolonging length of stay. The proportion of all LNF performed as day cases increased from 8% to 52% during the study period. Median operative time has significantly reduced from the first 20 consecutive LNF cases to the latest 20 cases [65 min (range 40-120 min) versus 48 min (range 25-72 min); p = 0.037]. At follow-up (median 7 weeks, range 2-31 weeks) 82% of patients had improvement in all presenting symptoms. Eight patients had postoperative complications [wound infection (n = 2), persistent regurgitation requiring laparoscopic division of a gastric band adhesion (n = 1), dysphagia (n = 5 with two patients requiring redo partial fundoplication and one patient requiring dilatation) and there were no conversions to open surgery. CONCLUSION: Day-case LNF is safe and effective for treating selected patients with gastroesophageal reflux disease (GERD) in a DGH. The proportion of day-case LNFs is increasing in our unit. Half of the LNFs in a DGH can be done as day cases. Experience is associated with a significant reduction in operative time.

Methyldibromo glutaronitrile contact allergy: effect of single versus repeated daily exposure.

Some types of cosmetic products such as hand soaps and creams are commonly used several times a day, especially in occupational use situations. Little has experimentally been shown of how the daily frequency of the application of an allergen in a product influences the allergic response. This study investigates the allergic responses elicited in presensitized individuals when exposed to a specific amount of allergen applied either in 1 application per day or distributed over 4 applications per day. As model allergen, the cosmetic preservative methyldibromo glutaronitrile (MDBGN) is used. 19 contact allergic individuals and 12 controls participated in a double-blind, randomized use test. To areas on the forearms were applied 2 drops either once daily of a solution containing 0.04% MDBGN or 4 times a day of a solution containing 0.01% MDBGN. 14 of 19 patients developed dermatitis following the application of approximately equal amounts of MDBGN on both arms. Controls were negative. In this experiment, applications of 0.04% MDBGN once daily or 0.01% MDBGN 4 times daily had, in a use test, approximately equal capabilities of provoking allergic contact dermatitis. This adds new knowledge to the risk assessment and regulation of cosmetic allergens. However, these results may be highly allergen dependent, and further studies are needed before more general conclusions can be made.

Methyldibromoglutaronitrile in rinse-off products causes allergic contact dermatitis: an experimental study.

BACKGROUND: The frequency of sensitivity to the cosmetic preservative methyldibromoglutaronitrile (MDBGN) has increased significantly in Europe. Most cases of allergic contact dermatitis from MDBGN are caused by leave-on cosmetic products. The risk of developing allergic contact dermatitis from rinse-off products has been less studied. OBJECTIVES: To investigate the allergic response elicited in presensitized individuals from exposure to a rinse-off product preserved with the maximum permitted level of MDBGN. METHODS: Nineteen contact allergic individuals and nine controls participated in a double-blind, randomized repeated open application test (ROAT) using two coded liquid soaps with and without MDBGN. Areas of 50 cm2 on the lower arms were washed with the soaps twice a day for up to 28 days; two of the subjects continued for 34 days. The subjects were also patch tested with a dilution series of MDBGN to determine their patch test threshold values. RESULTS: Seven presensitized individuals (37%) developed allergic contact dermatitis from the soap containing MDBGN. The mean dose of MDBGN per application was 2.2 micro g cm-2 and the reactions appeared between days 6 and 34. All nine controls had negative ROATs. The difference in reactivity between test subjects and controls was significant (one-sided Fisher's exact test, P = 0.04). Patch test threshold values ranged from < 0.001% to 0.2% MDBGN in ethanol/water. CONCLUSIONS: This study shows that the exposure to a rinse-off product containing the maximum permitted level of MDBGN can easily elicit an allergic response in presensitized individuals. Along with reported cases of induction and elicitation caused by MDBGN in rinse-off products the study indicates that the permitted level of MDBGN in rinse-off products is too high. We recommend that this level should be re-evaluated.

Dual regulatory control of a particle maturation function of bacteriophage P1.

A unique arrangement of promoter elements was found upstream of the bacteriophage P1 particle maturation gene (mat). A P1-specific late-promoter sequence with conserved elements located at positions -22 and -10 was expected from the function of the gene in phage morphogenesis. In addition to a late-promoter sequence, a -35 element and an operator sequence for the major repressor protein, C1, were found. The -35 and -10 elements constituted an active Escherichia coli sigma(70) consensus promoter, which was converted into a P1-regulated early promoter by the superimposition of a C1 operator. This combination of early- and late-promoter elements regulates and fine-tunes the expression of the particle maturation gene. During lysogenic growth the gene is turned off by P1 immunity functions. Upon induction of lytic growth, the expression of mat starts simultaneously with the expression of other C1-regulated P1 early functions. However, while most of the latter functions are downregulated during late stages of lytic growth the expression of mat continues throughout the entire lytic growth cycle of bacteriophage P1. Thus, the maturation function has a head start on the structural components of the phage particle.

Hypervolemia in men from fluid ingestion at rest and during exercise.

BACKGROUND: Plasma osmolality (Osm) is important for controlling and maintaining plasma volume (PV) and body water. The effect of oral rehydration fluids for ameliorating dehydration is well-established; but optimal composition and Osm of fluids for hyperhydrating normally hydrated subjects is less clear. METHODS: Six treatments were used without and with oral fluids of varying ionic and constituent concentrations for hyperhydrating six previously euhydrated men (30 +/- SD 8 yr, 76.84 +/- 16.19 kg, 73 +/- 12 ml.kg-1 PV, 40 +/- 10 ml.min-1.kg-1 peak VO2) sitting at rest for 90 min (VO2 = 0.39 +/- SE 0.02 L.min-1) and during subsequent 70 min of submaximal exercise (VO2 = 2.08 +/- SE 0.33 L.min-1, 70 +/- 7% peak VO2). The hypothesis was that the fluid composition is more important than plasma Osm for increasing PV in euhydrated subjects at rest and maintaining it during exercise. Drink formulation compositions, given at 10 ml.kg-1 body wt, (mean = 768 ml), for the sitting period were: Performance 1 (P1; 55 mEq Na+, 365 mOsm.kg H2O-1), P2 (97 mEq Na+, 791 mOsm.kg-1), P2G (113 mEq Na+, 4% glycerol, 1382 mOsm.kg-1), AstroAde (AA; 164 mEq Na+, 253 mOsm.kg-1), and 01 and 02 (no drinking). The exercise drink (10 ml.kg-1, 768 ml) was P1 for all treatments except 02 (no drinking); thus, drink designations were: P1/P1, P2/P1, P2G/P1, AA/P1, 0/P1, and 0/0. RESULTS: PV at rest increased (p < 0.05) by 4.7% with P1 and by 7.9% with AA. Percent change in PV during exercise was +1% to +3% (NS) with AA/P1; -6% to 0% (NS) with P1/P1, P2/P1, P2G/P1, and 0/P1; and -8% to -5% (p < 0.05) with 0/0. AA, with the lowest Osm of 253 mOsm.kg-1, increased PV at rest (as did P1) and maintained it during exercise, whereas the other drinks with lower Na+ and higher Osm of 365-1382 mOsm.kg-1 did not. CONCLUSION: Drink composition appears to be more important than its Osm for increasing PV at rest and for maintaining it during exercise in previously euhydrated subjects.

Effects of diet and exercise on energy expenditure in postmenopausal women.

The purpose of this study was to determine the effect of a 24-wk diet + exercise (DE) or diet-only program on basal metabolic rate (BMR), bone mineral density (BMD), energy expended during daily activities, muscle strength, and maximal oxygen consumption (VO2max) in 40 postmenopausal women. Daily energy need was determined by measuring BMR and assessing physical activity with 8-d self-reported activity records. The DE group consumed 2092 kJ/d less than the daily energy need and walked and performed strength-training exercises during which they expended an additional 837 kJ/d. The two diet-only groups consumed either 2092 kJ/d (D-2092) or 2929 kJ/d (D-2929) less than the daily energy need. BMD, BMR, muscle strength, VO2max, and energy expended during lying, sitting, standing, and walking were measured at baseline and after 12 and 24 wk of treatment. A significant decrease in BMR and energy expended during sitting and walking occurred in all groups, with no significant differences observed among groups. Although the declines in BMR were significant, they were small and may not have been physiologically relevant. No changes in BMD or VO2max occurred, whereas strength increased significantly in the DE group. The results showed that postmenopausal women significantly improved their body composition over a period of 6 mo without experiencing a large decline in BMR, BMD, or select components of energy expenditure.

Long-term effects of water-soluble dietary fiber in the management of hypercholesterolemia in healthy men and women.

Fifty-one healthy, moderately hypercholesterolemic men and women consuming their usual fat-modified diets completed a 6-month, randomized, double-blind, placebo-controlled, parallel comparison of 15 g/day supplemental water-soluble dietary fiber (WSDF; a mixture of psyllium, pectin, guar gum, and locust bean gum) and an inactive WSDF control (acacia gum). Compliance with the treatments was > 95%, adverse effects were minimal, and body weights remained constant. The WSDF mixture yielded 6.4% and 10.5% reductions in mean plasma total and low-density lipoprotein cholesterol concentrations, respectively, after 8 weeks, which were sustained at 16 and 24 weeks. Mean plasma high-density lipoprotein cholesterol and triglyceride concentrations were unchanged. No significant changes in mean plasma lipid or lipoprotein concentrations were observed in the control group. These data demonstrate that a WSDF approach to cholesterol management is effective as an adjunct to a fat-modified diet in healthy, moderately hypercholesterolemic men and women.

Pre-exercise hypervolemia and cycle ergometer endurance in men.

Time to exhaustion at 87-91% of peak VO2 was measured in 5 untrained men (age: 31 +/- 8 years, body mass: 74.20 +/- 16.50 kg, body surface area: 1.90 +/- 0.24 m2, peak VO2: 2.87 +/- 0.40 l min-1, plasma volume: 3.21 +/- 0.88 l; means +/-SD) after consuming nothing (N) or two fluid formulations (10 ml kg-1, 743 +/- 161 ml): Performance 1 (P1), a multi-ionic carbohydrate drink, containing 55 mEq l-1 Na+, 4.16 g l-1 citrate, 20.49 g l-1 glucose, and 365 mOsm kg-1 H2O, and AstroAde (AA), a sodium chloride-sodium citrate hyperhydration drink, containing 164 mEq l-1 Na+, 8.54 g l-1 citrate, <5 mg l-1 glucose, and 253 mOsm kg-1 H2O. Mean (+/-SE) endurance for N, P1 and AA was 24.68 +/- 1.50, 24.55 +/- 1.09, and 30.50 +/- 3.44 min respectively. Percent changes in plasma volume (PV) from -105 min of rest to zero min before exercise were -1.5 +/- 3.2% (N), 0.2 +/- 2.2% (P1), and 4.8 +/- 3.0% (AA; P < 0.05). The attenuated endurance for N and P1 could not be attributed to differences in exercise metabolism (VE, RE, VO2) from the carbohydrate or citrate, terminal heart rate, levels of perceived exertion, forehead or thigh skin blood flow velocity, changes or absolute termination levels of rectal temperature. Thus, the higher level of resting PV for AA just before exercise, as well as greater acid buffering and possible increased energy substrate from citrate, may have contributed to the greater endurance.

Reattaching salvageable crowns.

The technique of reattachment of broken, but otherwise intact, crowns is one worth exploring. The time constraints placed upon the dentist to evaluate this type of emergency patient can be quite burdensome. The technique offers an alternative solution to this problem. As dental practitioners, our first reaction to this type of emergency situation might include a series of logical steps to restore the tooth. These steps might include a new core build up with pins, then onto a temporary crown. A second alternative might be to initiate root canal therapy and manufacture a temporary post and crown. Still another option may include extraction of the tooth and an impression for an interim partial denture, later to be replaced by implant supported crowns, removable partial denture, or other prosthesis. Adding reattachment of the broken crown back onto the tooth gives just one more alternative to an otherwise lengthy and difficult set of possible solutions. Most of the more conventional types of treatment listed above can be quite time-consuming. Multiple appointments may be needed, and the shock in learning this reality may be overwhelming to the patient. Quite often, a patient that is in need of reattachment of a crown will have many other dental needs. Exhausting a patient's finances, as well as their time limits in restoring just one tooth may not be prudent. It may make more sense to repair, if only temporarily, one tooth and to go on to the next most pressing dental concern. Reattachment of the crown, although not always an easy solution, can be learned, and with practice, the technique can be expanded to include more difficult cases, including fractured bridges,and teeth with broken posts. These methods can be performed in one appointment with a high degree of success. Although it is best to advise the patient of the temporary nature of the treatment, it is quite likely that the repair will hold up almost as well as the original project.

The effect of acacia gum and a water-soluble dietary fiber mixture on blood lipids in humans.

Water-soluble dietary fibers (WSDF) are generally thought to lower cholesterol. This study compared the cholesterol-lowering effects of a medium viscosity WSDF mixture (psyllium, pectin, guar gum and locust bean gum) with an equal amount of WSDF from acacia gum, which has a lower viscosity. Hypercholesterolemic males (n = 13) and females (n = 16) were randomly assigned to one of two WSDF treatments provided in a low-calorie powder form for mixing into beverages (< 4 kcal/serving). Subjects were instructed to mix powders into their usual beverages and to consume them three times daily (5 g WSDF/serving) for 4 weeks while consuming their typical fat-modified diets. Exercise and body weights were also held constant. The WSDF mixture yielded a 10% decrease in plasma total cholesterol (from 251 +/- 20 to 225 +/- 19 mg/dL; p < 0.01), and a 14% reduction in low-density lipoprotein cholesterol (from 167 +/- 14 to 144 +/- 14 mg/dL; p < 0.001). No significant changes in plasma high-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol or triglycerides were observed. In contrast, the acacia gum-treated group showed no change in any plasma lipid parameters. The WSDF treatments did not produce significant changes in mean dietary intakes within or between treatment groups. These data support previous findings that a diet rich in select WSDF can be a useful cholesterol-lowering adjunct to a fat-modified diet, but that caution should be exercised in ascribing cholesterol-lowering efficacy to dietary fibers based solely on their WSDF classification. Finally, WSDF viscosity is a potential cholesterol-lowering factor to be explored further.

Role of water-soluble dietary fiber in the management of elevated plasma cholesterol in healthy subjects.

Guidelines for the use of water-soluble dietary fibers (WSDF) in the dietary management of elevated plasma cholesterol are not well-established. Consequently, 4 studies were conducted to explore the plasma lipid-lowering effects of a variety of WSDF. Studies were randomized, double-blind, placebo-controlled trials involving healthy men and women (plasma cholesterol greater than 5.17 mmol/liter; greater than 200 mg/dl). Study duration ranged from 4 to 12 weeks. The WSDF acacia gum yields a low viscosity, palatable beverage when mixed in water. However, despite its WSDF classification, acacia gum consumed for 4 weeks as the sole WSDF source (15 g of WSDF/day) or primary source in a WSDF mixture (17.2 g of WSDF/day; 56% derived from acacia gum) did not produce a significant lipid-lowering effect versus placebo. When 15 g of WSDF/day consisting of psyllium hust, pectin, and guar and locust bean gums (medium viscosity) was consumed for 4 weeks, significant reductions in cholesterol resulted (total cholesterol 8.3%, low-density lipoprotein cholesterol 12.4%; p less than 0.001) that were comparable to changes achieved with 10 g of WSDF/day from high-viscosity guar gum. The magnitude of the lipid-lowering effect was related to intake of WSDF ranging from 5 to 15 g/day (low-density lipoprotein cholesterol +0.8% [placebo], -5.6% [5 g/day], -6.8% [10 g/day], -14.9% [15 g/day]; p less than 0.01 for trend). The effects of WSDF on plasma lipids were similar for men and women. A diet rich in selected WSDF may be a useful adjunct to the dietary management of elevated plasma cholesterol.

Effect of protein dose on serum glucose and insulin response to sugars.

To clarify the effects of protein on insulin and glucose response to sugars, 14 healthy normal-weight males and females were fed test meals containing 0, 15.8, 25.1, 33.6, and 49.9 g protein along with approximately 58 g carbohydrate. Serum samples were obtained at fasting time zero and 15, 30, 60, and 120 min postprandial. Mean areas of the glucose curves above fasting decreased with increasing protein dose. Protein-containing meals produced significantly lower (p less than 0.01) areas than the protein-free meal and the relationship between blood glucose area and protein dose was significant (p less than 0.001). Protein-containing meals produced significantly greater (p less than 0.01) insulin areas compared with the protein-free meal. However, no differences in insulin areas among the protein-containing meals were observed. These data support previous studies showing a blood glucose moderating and insulin-enhancing effect of protein ingestion.

Repletion and depletion of serum alpha and beta carotene in humans with carrots and an algae-derived supplement.

A 10-day low-carotene diet phase (LCD), followed by a 7-day treatment phase (TP) and then another LCD, was adhered to by 32 adult human subjects. Serum alpha carotene (SAC) and serum beta carotene (SBC) levels were examined using HPLC and found to have decreased 44.7% and 35.8% respectively in the first LCD. Alpha and beta carotene, from algae-derived capsules and raw carrots, significantly increased SAC and SBC levels during the TP. Half-lives of SAC and SBC averaged 7.8 days and 12.4 days respectively during the two LCD. Serum vitamin A remained unchanged throughout the study.

Multivitamin-mineral supplementation: effects on blood chemistries of college-age women.

Forty-two female college students, age 18-29 yr. and consuming nutritionally balanced meals in the college cafeteria participated. Subjects discontinued all vitamin-mineral supplements (VMS) for 17 days and were randomly assigned to one of two treatments, either a placebo, or VMS supplying the United States Recommended Daily Allowance (USRDA) of all vitamins, zinc, iron, iodine, copper, and 60% of the USRDA of calcium, 50% of magnesium and 45% of phosphorus. Treatments were consumed for 77 days. Fasting pre-and post-treatment blood chemistries were compared. VMS yielded significant increases (p less than 0.05) in serum vitamin B-12 (+25.05 pg/ml), vitamin C (+0.35 mg/dl) and folate (+7.40 ng/ml). No significant changes (p greater than 0.05) in hematological or other blood chemistries were observed. Significant decreases in the number of below-normal serum indicators of vitamin status (p less than 0.05) and iron status (p less than 0.005) were seen with VMS. No significant changes were seen with placebo (p greater than 0.05).

Peritonitis from starch glove powder.

Contamination of surgical wounds by starch glove powders has produced peritoneal inflammation and adhesions in many patients. Some have required surgical operation because of possible infection, others because of obstruction of the intestine. Resolving granulomas and fibrosis have been observed as incidental asymptomatic lesions in some patients during reoperation for other conditions. Starch granules are probably capable of producing inflammation in any patient, and the degree is believed to be related to the amount of starch present. Care in removing glove powder from gloves before they are worn in an operation will diminish or eliminate the problem. Removal can be accomplished by rubbing the gloves with a moist sterile towel or laparotomy tape.