Summary 1.Earlier research has established a number of relationships between community structure and plant traits. However, these relationships are mediated by demographic processes that are constrained, but not determined, by the trait values, and involve responses of plants to their environments. In particular, life-history costs and associated trade-offs need to be examined at the level of demographic processes such as plant survival and reproduction, not only at the level of individual trait values. 2. We examined these demographic trade-offs using data on vegetative and seed reproduction from 951 species of the Central European flora kept in the Botanical Garden of Charles University in Prague. With each species grown under conditions close to its natural habitat, we view the data as information on vegetative and seed reproduction under favourable conditions. We used nonparametric tests and ordinal regressions to examine relationships of the vegetative and seed reproduction to each other, as well as to commonly used traits such as plant height, leaf size, specific leaf area, seed size and clonal traits. 3. There was an overall negative correlation between seed and vegetative reproduction, indicating trade-off between these two modes of reproduction. In contrast, there was no evidence of a trade-off between clonal and seed traits. 4. Traits of clonal growth were related to vegetative reproduction in the garden and seed trait to seed reproduction in the garden. Further, there were correlations between seed reproduction and clonal traits and vice versa. These results suggest that seed reproduction is associated with a wider array of traits than only seed traits, and vegetative reproduction with a wider array than clonal traits again indicating complex life-history relationships. These relationships did not change substantially after the incorporation of phylogenetic information. 5. Synthesis. The results suggest that trade-offs between vegetative and seed reproduction are not revealed by analysis of species traits, probably due to the fact that trade-offs often only arise due to life-history costs that are shaped by the local environment. This highlights the importance of examining life-history processes associated with trait values.

Background-We postulated that the variability of the phase shift between blood pressure and heart rate fluctuation near the frequency of 0.10 Hz might be useful in assessing autonomic circulatory control. Methods and Results-We tested this hypothesis in 4 groups of subjects: 28 young, healthy individuals; 13 elderly healthy individuals; 25 patients with coronary heart disease; and 19 patients with a planned or implanted cardioverterdefibrillator (ICD recipients). Data from 5 minutes of free breathing and at 2 different, controlled breathing frequencies (0.10 and 0.33 Hz) were used. Clear differences (PϽ0.001) in variability of phase were evident between the ICD recipients and all other groups. Furthermore, at a breathing frequency of 0.10 Hz, differences in baroreflex sensitivity (PϽ0.01) also became evident, even though these differences were not apparent at the 0.33-Hz breathing frequency. Conclusions-The frequency of 0.10 Hz represents a useful and potentially important one for controlled breathing, at which differences in blood pressure-RR interactions become evident. These interactions, whether computed as a variability of phase to define stability of the blood pressure-heart rate interaction or defined as the baroreflex sensitivity to define the gain in heart rate response to blood pressure changes, are significantly different in patients at risk for sudden arrhythmic death. In young versus older healthy individuals, only baroreflex gain is different, with the variability of phase being similar in both groups. These measurements of short-term circulatory control might help in risk stratification for sudden cardiac death. (Circulation. 2003;108:292-297.)

The aim of the study was to determine changes of baroreflex sensitivity in humans between 11 and 20 years of age. Continuous 5 min blood pressure recordings using a Finapres were taken in 415 healthy subjects while in a sitting, resting position (breathing at a frequency of 0.33 Hz). Beat-by-beat values of interbeat intervals (IBI) or heart rate, and systolic and diastolic blood pressures were measured. Baroreflex sensitivity in ms/mmHg (BRS) and in mHz/mmHg (BRSf) was determined at an average frequency of 0.1 Hz by spectral analysis. BRS did not correlate with age, but BRSf significantly decreased with age (p < 0.001). BRS correlated with mean IBI (p < 0.001) in all subjects and also in the particular subgroups, but BRSf was IBI-independent. Results of multiregression equations were BRS = 1.37 - 0.56 x age (years) + 0.02 x IBI (ms) (p < 0.001 for BRS vs. age and for BRS vs. IBI); BRSf = 34.74 - 0.97 x age (years) - 0.001 x IBI (ms) (p < 0.001 only for BRS vs. age), where age was measured in years and IBI was measured in ms. The limits of BRS were estimated for the total group: 5th percentile, 3.9; 50th percentile, 9.1; and 95th percentile, 18.7 ms/mmHg; and limits for BRSf were 5th percentile, 8.5; 50th percentile, 16.4; and 95th percentile, 33.6 mHz/mmHg. We conclude that IBI-dependent BRS was unchanged in the particular age groups, but the standardization of BRS on IBI decreased with age. BRSf was IBI-independent and better reflected the development of the BRS.

Lead nanoparticles (NPs) are released into air from metal processing, road transport or combustion processes. Inhalation exposure is therefore very likely to occur. However, even though the effects of bulk lead are well known, there is limited knowledge regarding impact of Pb NPs inhalation. This study focused on acute and subchronic exposures to lead oxide nanoparticles (PbO NPs). Mice were exposed to PbO NPs in whole body inhalation chambers for 4-72 h in acute experiment (4.05 × 10 PbO NPs/cm), and for 1-11 weeks in subchronic experiment (3.83 × 10 particles/cm in lower and 1.93 × 10 particles/cm in higher exposure group). Presence of NPs was confirmed in all studied organs, including brain, which is very important considering lead neurotoxicity. Lead concentration gradually increased in all tissues depending on the exposure concentration and duration. The most burdened organs were lung and kidney, however liver and brain also showed significant increase of lead concentration during exposure. Histological analysis documented numerous morphological alterations and tissue damage, mainly in lung, but also in liver. Mild pathological changes were observed also in kidney and brain. Levels of glutathione (reduced and oxidized) were modulated mainly in lung in both, acute and subchronic exposures. Increase of lipid peroxidation was observed in kidney after acute exposure. This study characterized impacts of short to longer-term inhalation exposure, proved transport of PbO NPs to secondary organs, documented time and concentration dependent gradual increase of Pb concentration and histopathological damage in tissues.

Morphologically defined traits are predictive of species abundance, and it is concluded that simultaneous investigation of several such traits can help develop hypotheses on specific processes (e.g. avoidance of self-competition, support of offspring) potentially underlying clonal growth effects on abundance. Garden performance parameters provide a practical approach to assessing the roles of clonal growth morphological traits (and LHS traits) for large sets of species.

The mild increase of BMI was associated with white-coat effect and a BRS and BRSf decrease. The greater increase of BMI was associated with hypertension and a deeper BRS and BRSf decrease. This greater decrease of BRS and BRSf in hypertensives was linked with the increased SBP-variability.

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