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As the fast development of online social media, social network services have become an important research area nowadays. Particularly, microblog as new social media needs more attention. Most of current studies are usually static descriptions or explanations of what already has happened. Limited study has been conducted focusing on SNS users and analysing their behaviors dynamically. In this paper, we firstly segment microblog users based on the recency and frequency of tweet and retweet behavior, then use probability models such as Pareto/NBD and BG/NBD to predict customer lifetime vitality. Our results showed that both Pareto/NBD model and BG/NBD model showed effective ability to fit and predict SNS users' usage behavior on microblog website. Tweet behaviors of sustainably active user base are more suitable for the probability models. Managerial implications of the two models should be highlighted as well. Interaction rate and dropout rate can be considered as the vitality index of the whole user base measuring how active users are and how likely a user is active. Managerial questions such as how active the users are in this platform now and how active the users will be in the future can be answered by applying those models.

This study investigated the relationship between nitrogen and carbon in the thalli of the lichen Evernia prunastri, with an emphasis on the role of the C/N balance in the response of this species to N excess. For this purpose, thalli collected at a remote site were sprayed for 5 weeks with NH4NO3 (0.05 and 1 M) and (NH4)2SO4 (0.025 and 0.5 M) solutions, and later analyzed for their C and N content. The results showed that the total N content of thalli increased and the total C content decreased along with increasing N concentration in the treatment solutions. Consequently, the C/N ratio also significantly decreased in treated samples. The Fv/Fm ratio, taken as a vitality index, turned out to be positively correlated with C content and negatively correlated with N content. It is suggested that N stress is caused by the lack of compensation for elevated ammonium levels with higher C assimilation. It is concluded that E. prunastri is a suitable bioindicator of N pollution and that the C/N ratio deserves further investigation as a promising tool for early warning of N excess.

One of the fundamental requirements of government-funded economic development activities is a provision guaranteeing citizen participation. An effective citizen participation tool must be understandable to a general audience yet must not obscure the inherent system characteristics of the local development process. To meet these two criteria, our vitality index uses a visual profile of twenty-four demographic, economic, quality of life, geographic, and environmental measures. The index is constructed by transforming the raw data for each category into standard deviations from the state average. This visual profile can encourage the participation of citizens with varying degrees of previous involvement in economic development planning. An example of the vitality index is given using four Nebraska counties.

In long-term forest monitoring, tree crown condition has been visually rated to diagnose tree vigor and forest condition. However, visual estimates are subjective. A semiautomatic image analysis system, called CROCO, was developed to estimate crown condition quantitatively. CROCO calculates a DSO value which decrease with increasing crown transparency. This study aims to verify visual estimates objectively using CROCO and to assess characteristics of visual estimates and DSO values by comparing the effectiveness as indicators of radial growth. Crown condition of Abies mariesii was visually rated using a vitality index, and DSO values of the same trees were calculated. When the top of the tree was intact, the trees with a higher vitality index showed a significantly higher DSO. Vitality index showed the strongest relationship with DBH increment for 8 years. DSO had a significant relationship with DBH increment by adding information of the crown top condition. Analysis of tree crown images is effective to verify visual estimates. Vitality index is a synthetic index involving factors affecting radial growth. DSO could be utilized similarly to vitality index, as an indicator of radial growth, by addition of information on crown size and/or shape.

Objective To analyze the genetic difference of biological characters on germplasm resources of Sophora alopecuroides. Method Twenty-three populations of S. alopecuroides from Ningxia, Gansu, Qinghai, Xinjiang and Inner Mongolian were used to analyze the seed size, 1 000-grain weight, and germination characteristics and so on. Result It showed that there were significant differences in seed size, 1 000-grain weight and the vitality of seeds. The biggest seed of S. alopecuroides was 4.7 mm x 3.5 mm, and the smallest was 3.8 mm x 2.9 mm, and the 1 000-grain weight was 15-26 g. Results of seeds vitality in 8 populations indicated that the highest vitality of seeds were No. 103 and No. 122. The germination index was 36.51 and 36.24 respectively, and the vitality index was 1 323.49 and 1 274.56. The coefficient of variation in seed traits exceeded 10% except the seed size. Conclusion There are some differences and different heredity background in various S. alopecuroides germplasm resources.

After developing an outer model of the famous-brand product vitality, this paper presents the concept and calculation formula of the famous-brand product vitality index, the concept of customer elasticity on the basis of Product Famous-brand Vitality Index. The paper also takes Haier's product as an example to calculate out its famous-brand vitality index, the customer elasticity index at customer's different age and income levels. Based on the analyses of the result. the paper gives some suggests for Haier Group.

The decision-making process for the management of locally advanced prostate cancer is very complex for both patients and health-care professionals. The Vitality Index can be used to help tailor therapy approaches to match the individual lifestyle needs of patients.

In our previous publication (Mayevsky et al SPIE 5326: 98-105, 2004) we described a multiparametric fiber optic system enabling the evaluation of 4 physiological parameters as indicators of tissue vitality. Since the correlation between the various parameters may differ in various pathophysiological conditions there is a need for an objective quantitative index that will integrate the relative changes measured in real time by the multiparametric monitoring system into a single number-vitality index. Such an approach to calculate tissue vitality index is critical for the possibility to use such an instrument in clinical environments. In the current presentation we are reporting our preliminary results indicating that calculation of an objective tissue vitality index is feasible. We used an intuitive empirical approach based on the comparison between the calculated index by the computer and the subjective evaluation made by an expert in the field of physiological monitoring. We used the in vivo brain of rats as an animal model in our current studies. The rats were exposed to anoxia, ischemia and cortical spreading depression and the responses were recorded in real time. At the end of the monitoring session the results were analyzed and the tissue vitality index was calculated offline. Mitochondrial NADH, tissue blood flow and oxy-hemoglobin were used to calculate the vitality index of the brain in vivo, where each parameter received a different weight, in each experiment type based on their significance. It was found that the mitochondrial NADH response was the main factor affected the calculated vitality index.

The elderly with dementia show distinct characteristics and different remaining abilities even in advanced disease. For improvement of the quality of care for the elderly, it is essential to evaluate their remaining abilities. Mini-communication Test, Braiding Test and Vitality Index have been developed to evaluate the abilities remaining in the elderly with severe dementia. The reliability, validity and usefulness of these new methods were discussed.

Influence of ultraviolet A (UV-A) exerted on ultraviolet B (UV-B) damaged peanut leaves was examined by using the laser-induced fluorescence (LIF) method. The vitality index of the leaves was estimated from the measurement of the induction kinetics of chlorophyll fluorescence that was done in parallel with LIF spectra measurement. Visible ray irradiation of several hours to the UV-B damaged leaves recovered the vitality index of the leaves, while UV-A irradiation for the same period to the UV-B damaged leaves decreased the vitality index remarkably. No significant decrease of the vitality index was seen by the UV-A irradiation of several hours to the control (damage-less) leaves. It was understood that the UV-A irradiation to the UV-B damaged leaves causes the synergistic decrease of the vitality index. It is known that UV-absorbing pigments induced by UV-B irradiation are able to reduce not only UV penetration into the leaf but also photo-system II damage of the leaves. In this experiment, it is thought that the UV-absorbing pigments were decomposed by the UV-A irradiation and so further decreased in the vitality index of the leaves.

We used simulated microgravity to treat aged pea seeds, in order to observe its effect on seed vigour and related physiological properties. The result shows that microgravity obviously promotes the germination rate, vitality index, germination index, and keeps the activity of protective enzyme, with conductivity and the content of MDA decreased. These effects gradually disappeared for a certain period after the microgravity administration.

We investigated the relation of the age trajectory of physiological indicators of the average metabolic activity of organisms in a population to the age-specific population mortality rate. We show that a metabolic rate indicator (MRI) can be estimated using traditional physiological measures, such as homeostatic serum glucose concentration, vital capacity, and such. Estimates of the MRI were made from data collected in the Multiple Risk Factor Intervention Trial (MRFIT) study. The relation of the empirical mortality rate and MRI was also tested using MRFIT data. The age trajectory of MRI was evaluated using Swedish mortality data. The mortality results reproduce the "Strehler and Mildvan effect." The average rate of decline of MRI with age coincides with estimates predicted by Strehler using other methods. Possible extensions of the method are discussed.

Amongst the 7486 babies born at the Department of Gynecology and Obstetrics in Cologne from 1974 to 1978, 536 neonates displayed a birthweight of more than 4000 g. The obstetrically relevant data from 523 deliveries were evaluated retrospectively. We compared and contrasted the results with a reference group of 511 neonates with a normal weight (2500-3999 g) according to the matched pair principle. The incidence of macrosomic neonates amounted to 7.2% of total deliveries in the observation period. On comparing the average age of the mothers, we found a rise from 27.4 years (mothers of the reference group) to 29.4 years in mothers of babies weighing 4000-4499 g and 30.3 years in mothers with babies weighing 4500 g and more. The proportion of the pregnant mothers over 40 years old was 4.6% as compared to 2% in the reference group in macrosomic babies. The parities show a decrease of the primiparae and an increase of the multiparae amongst mothers of macrosomic babies. The rate of primiparae was 49.3% in the group of babies of normal weight as compared to 33.3% in moderately overweight (4000-4499 g) and 23.4% in the highly overweight babies (4500 g and over). The large proportion of adipose mothers in neonatal macrosomy was also striking. The average weight of the women at the end of pregnancy was 71.4 kg in the reference group and rose to 78.6 or 86.8 kg, respectively, in the mothers of macrosomic neonates. In 453 puerperal mothers who had delivered a macrosomic baby, an oral glucose tolerance test (oGTT) was performed in the first 72 hours after delivery. This was pathological in 25.8% of mothers of moderately overweight children, and was pathological in 29.7% of mothers of distinctly overweight babies. This thus confirmed the correlation between diabetogenic metabolic stress and macrosomy. Evaluation of the course of birth revealed a distinctly raised risk of asphyxia with restriction of the vitality index and increase of abnormal internal and neurological features especially for the neonates with a weight of 4500 g and more. Our goal must therefore be to diagnose macrosomy better than so far by foetal biometry in order to counteract the risks described by prospective control of pregnancy and delivery.

A definition of stress to plants and a general stress concept are presented including a list of possible major natural and anthropogenic stress factors. It is shown that the white light or laser-induced chlorophyll fluorescence of predarkened leaves is a very suitable tool for early stress detection in plants as well as for regeneration studies. The different chlorophyll fluorescence parameters to be measured are: variable fluorescence (ratio fmax/fo), the vitality index (fluorescence decrease ratio, Rfd-values), the stress adaption index Ap, the fluorescence spectra (ratio F690/F735) and the photochemical Q- and non-photochemical E-quenching (qQ and qE). Some examples of the measurement of these parameters under stress conditions are given.

The chlorophyll fluorescence vitality indices of green leaves (the Rfd-values) were comparatively determined from the same leaf samples using 1) a self-constructed, red laser equipped, portable field chlorophyll fluorometer (Rfd-values in the 690 and 730 nm region) and 2) the PAM-fluorometer (Rfd-values in the 730 nm region). The results indicate that the PAM-fluorometer, originally built for the measurement of Q- and E-quenching, can also be applied to determine the Rfd-values (in the 730 nm region) using its continuous white saturating light source for fluorescence induction. Since Rfd-values as a vitality index contain additional and complementary physiological information on the whole process of photosynthesis, it is strongly recommended to measure in all leaf samples — in addition to Q- and E-quenching — also the Rfd-values. Though the PAM-fluorometer can be successful used for the determination of Rfd-values, the portable field fluorometer has the advantage that it also permits calculation of the stress adaptation index Ap from the two Rfd-values at 690 and 730 nm.

The chlorophyll-fluorescence signatures of the needles of healthy (damage class 0/1, Althof, 450 m above sea level) and damaged spruce trees (damage class 3/4, Mauzenberg 700 m altitude) in the northern Black Forest were determined by using a self-constructed portable field fluorometer as well as the PAM-fluorometer. These new instruments allow measurement of the red-laser-induced chlorophyll fluorescence induction kinetics (Kautsky effect) at 690 and 730 nm, the determination of the Rfd-values (Rfd 690 and Rfd 730) as vitality index, and the stress-adaptation index Ap as well as the photochemical Q-quenching and the non-photochemical E-quenching of the spruce needles. The differences in the fluorescence signatures and photosyn-thetic activity between the needles of healthy and damaged trees are presented. In the needles of the damaged trees the Rfd-values, the capacity for photosynthesis and the reoxidation of QA are strongly reduced, whereas the non-photochemical E-quenching is increased.