Tree height strongly affects estimates of water-use efficiency responses to climate and CO2 using isotopes.

Various studies report substantial increases in intrinsic water-use efficiency (W i ), estimated using carbon isotopes in tree rings, suggesting trees are gaining increasingly more carbon per unit water lost due to increases in atmospheric CO2. Usually, reconstructions do not, however, correct for the effect of intrinsic developmental changes in W i as trees grow larger. Here we show, by comparing W i across varying tree sizes at one CO2 level, that ignoring such developmental effects can severely affect inferences of trees' W i . W i doubled or even tripled over a trees' lifespan in three broadleaf species due to changes in tree height and light availability alone, and there are also weak trends for Pine trees. Developmental trends in broadleaf species are as large as the trends previously assigned to CO2 and climate. Credible future tree ring isotope studies require explicit accounting for species-specific developmental effects before CO2 and climate effects are inferred.Intrinsic water-use efficiency (W i ) reconstructions using tree rings often disregard developmental changes in W i as trees age. Here, the authors compare W i across varying tree sizes at a fixed CO2 level and show that ignoring developmental changes impacts conclusions on trees' W i responses to CO2 or climate.

Bacterially mediated removal of phosphorus and cycling of nitrate and sulfate in the waste stream of a "zero-discharge" recirculating mariculture system.

Simultaneous removal of nitrogen and phosphorus by microbial biofilters has been used in a variety of water treatment systems including treatment systems in aquaculture. In this study, phosphorus, nitrate and sulfate cycling in the anaerobic loop of a zero-discharge, recirculating mariculture system was investigated using detailed geochemical measurements in the sludge layer of the digestion basin. High concentrations of nitrate and sulfate, circulating in the overlying water (∼15 mM), were removed by microbial respiration in the sludge resulting in a sulfide accumulation of up to 3 mM. Modelling of the observed S and O isotopic ratios in the surface sludge suggested that, with time, major respiration processes shifted from heterotrophic nitrate and sulfate reduction to autotrophic nitrate reduction. The much higher inorganic P content of the sludge relative to the fish feces is attributed to conversion of organic P to authigenic apatite. This conclusion is supported by: (a) X-ray diffraction analyses, which pointed to an accumulation of a calcium phosphate mineral phase that was different from P phases found in the feces, (b) the calculation that the pore waters of the sludge were highly oversaturated with respect to hydroxyapatite (saturation index = 4.87) and (c) there was a decrease in phosphate (and in the Ca/Na molar ratio) in the pore waters simultaneous with an increase in ammonia showing there had to be an additional P removal process at the same time as the heterotrophic breakdown of organic matter.

Aggressive dream content without daytime aggressiveness in REM sleep behavior disorder.

BACKGROUND: REM sleep behavior disorder (RBD) is characterized by vigorous sleep motor activity associated with dream mentation. Patients with RBD frequently report action-filled and violent dreams. OBJECTIVE: To systematically assess dream characteristics and daytime aggressiveness in patients with RBD and controls. METHODS: Forty-nine patients with polysomnographic-confirmed RBD diagnosis and 71 age- and sex-matched controls were asked to recall the most recent dreams and to complete the Aggression Questionnaire (AQ). Forty-one patients with RBD (81.6%; 36 men, 5 women; mean age: 67.5 +/- 7.5 years) and 35 controls (49.3%; 30 men, 5 women; mean age: 69.1 +/- 5.9 years) were able to remember their dreams and a total of 98 (RBD) and 69 (controls) dreams were collected in the two groups. Verbatim dream descriptions were scored and analyzed according to the Hall and Van De Castle method. RESULTS: Patients with RBD showed a higher percentage of dream with at least one aggressive episode (DWA) than controls (66% vs 15%; p < 0.00001), a higher aggression/friendliness interaction ratio (86% vs 44%; p < 0.0001), and a greater frequency of animal characters (19% vs 4%; p = 0.0001). In contrast to controls, no patient with RBD had dreams with elements of sexuality (0% vs 9%; p < 0.0001). The two groups did not differ in total AQ scores, except for a lower score on the physical aggressiveness subscale in patients with RBD compared to control subjects (16.5 +/- 6.4 vs 20.4 +/- 8.3; p = 0.034). No correlation was observed between dream aggressiveness and age, duration, or frequency of RBD symptoms. CONCLUSIONS: Dreams in patients with REM sleep behavior disorder were characterized by an elevated proportion of aggressive contents, despite normal levels of daytime aggressiveness. Dreams with aggressiveness and the known excessive phasic muscle activity during REM sleep may be related to the hyperactivity of a common neuronal generator.

Personality traits and metabolic control: a study in insulin-dependent diabetes mellitus patients.

BACKGROUND: In the present study the authors evaluated the relationship between personality traits (according to DSM-III-R) and poor metabolic control in an adult onset insulin-dependent diabetes mellitus sample (n = 77). METHODS: Personality traits were assessed with the Personality Diagnostic Questionnaire--Revised. Metabolic control was evaluated through glycosilated hemoglobin (HbA1c): poor metabolic control was defined as HbA1c > or = 9% (normal values < 6.0%). RESULTS: Principal Component Analysis revealed three personality profiles: 'Cluster A/C Mixed', 'Cluster B Dependent' and 'Cluster B Aggressive'. Oneway ANCOVA, using sex as covariate, revealed a significant association (p = 0.01) only between poor metabolic control and Cluster B Dependent profile. No correlation was found between HbA1c and the other profiles. CONCLUSION: These data suggest that a specific personality profile is associated with poor metabolic control.

Effects of personality on metabolic control in IDDM patients.

OBJECTIVE: The aim of this study was to evaluate the relationship between poor metabolic control and maladaptive personality traits (according to the Diagnostic and Statistical Manual of Mental Disorders, Third Edition-Revised) in an adult-onset insulin-dependent diabetes mellitus sample group (n = 77). RESEARCH DESIGN AND METHODS: Metabolic control was evaluated through glycosylated hemoglobin (HbA1c). Personality traits were assessed with the Personality Diagnostic Questionnaire-Revised, a self-administered questionnaire. Residual pancreatic secretion (fasting serum C-peptide) was also evaluated. RESULTS: Principal components analysis revealed three personality profiles: "withdrawn-suspicious" (P1), "dramatic-dependent" (P2), and "aggressive-irresponsible" (P3). Multiple linear regression analysis showed that C-peptide levels and P2 personality profiles were significant and independent predictors of HbA1c plasma levels: P2 predicted high HbA1c values and C-peptide predicted low HbA1c levels. CONCLUSIONS: These data suggest that a P2 personality profile is a significant predictor of poor metabolic control.