Determining the biomass fraction of mixed waste fuels: A comparison of existing industry and (14)C-based methodologies.

(14)C analysis of flue gas by accelerator mass spectrometry (AMS) and liquid scintillation counting (LSC) were used to determine the biomass fraction of mixed waste at an operational energy-from-waste (EfW) plant. Results were converted to bioenergy (% total) using mathematical algorithms and assessed against existing industry methodologies which involve manual sorting and selective dissolution (SD) of feedstock. Simultaneous determinations using flue gas showed excellent agreement: 44.8 ± 2.7% for AMS and 44.6 ± 12.3% for LSC. Comparable bioenergy results were obtained using a feedstock manual sort procedure (41.4%), whilst a procedure based on selective dissolution of representative waste material is reported as 75.5% (no errors quoted). (14)C techniques present significant advantages in data acquisition, precision and reliability for both electricity generator and industry regulator.

[Hypnotherapy for irritable bowel syndrome--a systematic review]. / Hypnotherapeutische Interventionen beim Reizdarmsyndrom - eine systematische Ubersicht.

The Irritable bowel syndrome (IBS) is a highly prevalent functional disorder with a remarkable clinical and economic impact. Several pathogenetic factors of IBS are discussed and summarised within a bio-psycho-social model. Data from published hypnotherapeutic interventions with approximately 800 patients show long-lasting symptom relief. The underlying mechanisms of action are not well understood. Nine mechanism studies show influences of hypnosis on colorectal sensitivity, colorectal motility and mental strain (anxiety, depression, maladaptive cognitions). Results are often contradictory and effects of hypnosis on several of the proposed pathogenetic factors are not examined at all. This paper reviews previous studies on hypnotherapy in IBS patients with a focus on symptom relief and mechanisms of action.

Chemical interactions with snow: understanding the behavior and fate of semi-volatile organic compounds in snow.

Snow plays an important role in providing atmospherically derived semi-volatile organic compounds (SVOCs) to regions of high latitude and altitude. The accumulated winter snowpack serves as a reservoir for SVOCs, which may then be released to arctic/alpine catchments during seasonal snowmelt or entrained into deeper layers of snow and ice. This paper provides a review of the occurrence of SVOCs in snow, exploring sampling methodologies and field measurements. Furthermore, chemical fate following snowfall and the propensity of SVOCs to undergo revolatilization with snow metamorphosis are examined along with air-snow partitioning and the role of physical parameters such as snow density and snow surface area in controlling vapor-sorbed levels. Snowmelt and firnification processes are described, and the latter are related to SVOC measurements made in deeper snow layers and glacial ice cores. Evidence is provided that suggests that those SVOCs that possess relatively higher snow interfacial/air partitioning coefficients (K(iasnow)) or lower Henry's Law constants may be more efficiently retained in snow, with implications for the occurrence of currently used pesticides in the temperate mountain snowpack.

Rapid changes in PCB and OC pesticide concentrations in arctic snow.

The short-term fate of polychlorinated biphenyl (PCB) and organochlorine (OC) pesticides in the surface snowpack was investigated by taking consecutive air and snow samples over a 12 day period at Tromsø in the Norwegian Arctic. A wide range in PCB and OC pesticide concentrations was observed in snow and was attributed to the systematic decrease in concentrations that occurred over the study period. For example, sigmaPCB concentrations ranged from 2500 to 300 pg L(-1) (meltwater) with a rapid decrease observed during the first 96 h. Rates of decline (ks) conformed to first-order kinetics, with similar rates observed for all compounds measured in this study (k5 = 0.01 +/- 0.001 h(-1)). Because the particle bound fraction accounted for <10% of the individual PCB and OC burden in the snow, then the fraction lost may be accounted for by desorption, following notable increases in snow density (and presumably, decreases in snow surface area). The fraction of chemical present in the fresh snow (phis) was found to be exponentially related to changes in snow density (deltarho). Relatively small increases in p following snowfall result in a large loss of sorbed chemical, presumably due to decreases in snow surface area. Later sampling of the same snow layer, but buried under fresh snowfall, revealed a notable increase in both PCB and OC concentrations. This would indicate a possible downward migration of these chemicals from the fresh snow into deeper snow layers, suggesting that re-emission of desorbed chemical from the interstitial pore spaces to the overlying atmosphere may be complicated by this process.

Polychlorinated naphthalenes in air and snow in the Norwegian Arctic: a local source or an Eastern Arctic phenomenon?

PCNs were measured in air and snow during separate field campaigns at Ny-Alesund (April 2001) and Tromsø (February/March 2003) in the Norwegian Arctic. Air concentrations ranged from 27 to 48 and 9 to 47 pg sigmaPCN m(-3) for Ny-Alesund (n=6) and Tromsø (n=10), respectively. These concentrations (including the tri-chlorinated naphthalenes) greatly exceeded concentrations previously measured in the Canadian Arctic, but did fall within the upper range of concentrations observed over the eastern Arctic Ocean and regional seas. Local sources appear to be affecting concentrations observed at both sites, with the presence of several hexa-chlorinated naphthalenes at Tromsø probably attributed to local/regional sources. Use of air mass back trajectories at Tromsø revealed that background air concentrations in the Norwegian Arctic are likely to range between <9 and 20 pg sigmaPCN m(-3) and that contemporary concentrations derived close to potential sources (i.e. arctic towns) may equal or exceed those of PCBs. The mean concentration in surface snow was 350 and 240 pg sigmaPCN L(-1) (meltwater) (or 0.014 and 0.01 pg g(-1) (snow)) at Ny-Alesund and Tromsø, respectively. The wide variation in concentrations observed between fresh snowfalls could be explained by different snow densities (as a surrogate of snow surface area), rather than attributed to varying air concentrations. A statistically significant inverse relationship was found between snow density and concentrations of tri- to penta-chlorinated homologues and compliments similar findings for the polychlorinated biphenyls (PCBs). This suggests that the vapour-sorbed quantity changes rapidly with snow ageing/compaction; with implications for the fate of these chemicals in the Arctic.

Use and validation of novel snow samplers for hydrophobic, semi-volatile organic compounds (SVOCs).

Two novel gas-tight snow samplers (snow-can and snow-tube) are presented and the performance of the snow-can in a field trial was assessed. The methodology for the sampling, extraction and analysis of persistent organic pollutants (POPs) are detailed. These samplers allow the various components of a snow sample to be analysed separately; these included the meltwater (MW), particulate matter (GFF) and vapour in the headspace (HS). Snow samples collected on the Punta Indren glacier in the Italian Alps revealed the occurrence of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OC). Replicate samples of the same snow type were undertaken as a test of sampling precision. Relative standard deviations (RSDs) for SigmaPCBs and SigmaPAHs were approximately 30% and approximately 35% respectively. The lowest precision was found for the particle-laden snow, notably for the heavier PCB homologues. For the chlorinated compounds, the pesticides lindane and endosulfan-I had the highest levels in snow, with mean concentrations of 402 and 103 pgl(-1) (snow meltwater) respectively. The vapour present in the headspace (HS) comprised a minor component of a collected sample for all compounds, but HS concentrations for three lighter PAHs gave good agreement with those calculated based on their dimensionless Henry's law constants. This suggests that volatilisation during melting of aged snow-can be reasonably predicted with knowledge of the temperature-dependent Henry's law constant.

Underreporting of energy intake in an elderly German population.

OBJECTIVES: Within the longitudinal study on nutrition and health status in an aging population in Giessen, Germany (GISELA), the underreporters of energy intake (EI) were identified and characterized. METHODS: EI was assessed in 238 female and 105 male participants of the GISELA study (age range = 60-89 y) by means of a 3-day estimated dietary record developed especially for this study. Resting metabolic rate (RMR) was measured by indirect calorimetry after an overnight fast. EI was expressed as a multiple of RMR and subjects with an EI:RMR ratio below 1.073 were classified as underreporters. RESULTS: Mean EI:RMR was 1.62 +/- 0.46 in females and 1.53 +/- 0.46 in males; 7.6% of the females and 16.2% of the males were identified as underreporters. They showed lower levels of education and significantly greater body weight, body mass index, and fat mass than the adequate reporters. Further, underreporters stated more often than adequate reporters that they want to lose weight. Except for beta-carotene in males, reported nutrient intakes were significantly lower in underreporters than in adequate reporters. Carbohydrate and fat intake in both sexes, protein intake in females calculated as a percentage of EI, and vitamin and mineral densities were not affected by underreporting. CONCLUSIONS: The results indicate that underreporting of EI is related to a low educational level and greater body weight, body mass index, and fat mass and affects all nutrients. These findings should be considered when the association between nutrition and health status is investigated in the elderly.

Effects of fat mass and body fat distribution on resting metabolic rate in the elderly.

The aim of the present study was to investigate the relationship between resting metabolic rate (RMR) and fat-free mass, fat mass, and body fat distribution in 164 women (age 60 to 85 years; body mass index [BMI], 18.5 to 35.6 kg/m(2)) and 98 men (age 60 to 85 years; BMI, 18.3 to 36.5 kg/m(2)). After an overnight fast, RMR was assessed by indirect calorimetry and body composition by bioelectrical impedance analysis. Waist-to-hip ratio (WHR) was used to determine fat distribution. Results from linear regression analysis showed that most of the variance in RMR could be attributed to fat-free mass in women (R(2) = 0.54) and men (R(2) = 0.44), respectively. Fat mass explained an additional 3% and 2% of the variability in RMR in women and men, respectively. In stepwise multiple regression analysis, considering body composition and fat distribution, only fat-free mass and WHR were significant predictors of RMR in both sexes. In addition to fat-free mass, in women 6% and in men 8% of the variability in RMR was attributable to WHR. Grouping subjects according to their WHR, RMR, and RMR adjusted for fat-free mass and fat mass showed a significant increase with increasing WHR in both sexes. Results indicate that RMR not only depends on fat-free mass but also is influenced by fat mass, especially by fat distribution. These findings support our hypothesis of an elevated RMR with increasing abdominal body fat as a direct consequence of its greater metabolic activity.

Prolonged tomato juice consumption has no effect on cell-mediated immunity of well-nourished elderly men and women.

The immunomodulatory potential of carotenoids has been investigated thoroughly only for beta-carotene. Data on the immunomodulatory activity of other carotenoids such as lycopene are scarce. The objective of this study was to investigate the effects of prolonged tomato juice consumption on cell-mediated immunity of well-nourished healthy elderly persons. In an intervention study, 33 female and 20 male subjects (aged 63-86 y) consumed 330 mL/d tomato juice (47.1 mg/d lycopene) or mineral water for 8 wk. Immune status was assessed by measuring number and lytic activity of natural killer (NK) cells, secretion of cytokines [interleukin (IL)-2, IL-4, tumor necrosis factor-alpha (TNF-alpha)] by activated peripheral blood mononuclear cells (PBMC), lymphocyte proliferation, and delayed-type hypersensitivity (DTH) skin responses. Tomato juice consumption resulted in significantly increased plasma lycopene and beta-carotene concentrations over time. In both treatment groups, TNF-alpha and IL-4 secretion were increased at the end of the intervention period, whereas IL-2 secretion was decreased. Tomato juice consumption had no effect on lymphocyte proliferation, DTH or the number of NK cells. Lytic activity of NK cells was increased in both groups at the end of the intervention period. In conclusion, these results show that prolonged tomato juice consumption increased plasma lycopene concentrations without significantly affecting cell-mediated immunity in well-nourished elderly subjects.

Resting metabolic rate, body composition, and serum leptin concentrations in a free-living elderly population.

OBJECTIVE: The present study investigated the relationship between serum leptin concentrations and resting metabolic rate (RMR) in a large study group of elderly individuals with special consideration of body composition and body fat distribution as possible confounders. DESIGN AND METHODS: The subjects were 122 women (age: 69+/-6 years, body mass index (BMI): 26.3+/-3.6 kg/m(2)) and 82 men (age: 69+/-5 years, BMI: 26.0+/-2.6 kg/m(2)). RMR was measured by indirect calorimetry and body composition by the bioelectrical impedance method. Serum leptin levels were determined by radioimmunoassay. RESULTS: There was a strong correlation between fat mass (FM) and serum leptin levels in both sexes. An age-related decline in leptin levels adjusted for FM was observed only in the women. After adjustment of RMR for both fat-free mass (FFM) and FM, leptin levels were not associated with RMR. In stepwise multiple regression analysis, FFM was the main predictor of RMR, explaining 35.8% and 47.6% of the variance of RMR in men and women respectively. FM did not explain variance in RMR in men, but accounted for 2.6% of the variance in RMR in women. Waist-hip-ratio and age influenced RMR only in males, explaining 5.7% and 4.0% of the variance in RMR respectively. CONCLUSION: Leptin is not a significant predictor of RMR in the elderly, but body composition and distribution of body fat are significantly associated with RMR.

Validation of a self-administered 3-day estimated dietary record for use in the elderly.

AIM OF THIS STUDY: was to assess the validity of a 3-day estimated dietary record, especially developed for the longitudinal study on nutrition and health status in an aging population (aged > or = 60 years) in Giessen, Germany. METHODS: The dietary record comprises 146 food items. Portion sizes of the foods consumed were estimated by means of household measures and corresponding dimensions. The validity of the dietary record was evaluated by means of nitrogen excretion in the 24 h urine in 14 women and 9 men, and by comparing energy intake and basal metabolic rate determined by indirect calorimetry in 238 women and 105 men. RESULTS: Neither in women nor in men were any differences found between calculated nitrogen intake (13.4 +/- 2.2 g and 15.0 +/- 2.0 g, respectively) and nitrogen excretion (12.9 +/- 2.1 g and 15.7 +/- 3.0 g, respectively). The ratio between reported energy intake and basal metabolic rate was 1.62 +/- 0.46 in women and 1.53 +/- 0.46 in men. Regarding energy intake, 7.6% of the females and 16.2% of the males were classified as under-reporters. They show a significantly higher body weight and BMI than the adequate reporters. CONCLUSION: The results have proved the new 3-day estimated dietary record as suitable to determine energy and nutrient supply of the elderly.