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We evaluated rat bone viability using a bone viability index (BVI). To evaluate hypothermic ischaemic bone injury, 21 amputated hind limbs of Fischer rats were preserved at hypothermia (4°C) for 1, 3 and 6 hours. To evaluate hypothermic ischaemia/reperfusion injury, another 28 amputated limbs were transplanted to recipient rats after hypothermic ischaemia for 3 and 6 hours, respectively. Total RNA isolated from each tibia was fractionated by electrophoresis and hybridised with ³²P-labelled cDNA of GAPDH, and the radioactivity of intact and degraded GAPDH mRNA measured. BVI was calculated as follows, BVI = {A / (A + B)} × 100, where A and B represent the radioactivities corresponding to intact and degraded GAPDH mRNA bands, respectively. In the hypothermic ischaemic insult group, BVIs were comparable to those of controls. However, in the 3-hour hypothermic ischaemia/reperfusion group, BVI was lower than that of the controls. Likewise, there was a significant difference between the 6-hour ischaemia/reperfusion group and controls. These results showed that bone viability decreased even after just a 3-hour hypothermic ischaemia/reperfusion.

In a numéraire-independent framework, we study a financial market with $N$ assets which are all treated in a symmetric way. We define the fundamental value ^∗S of an asset $S$ as its super-replication price and say that the market has a strong bubble if ^∗S and $S$ deviate from each other. None of these concepts needs any mention of martingales. Our main result then shows that under a weak absence-of-arbitrage assumption (basically NUPBR), a market has a strong bubble if and only if in all numéraire s for which there is an equivalent local martingale measure (ELMM), asset prices are strict local martingales under all possible ELMMs. We show by an example that our bubble concept lies strictly between the existing notions from the literature. We also give an example where asset prices are strict local martingales under one ELMM, but true martingales under another, and we show how our approach can lead naturally to endogenous bubble birth.

Viability theory can be applied for determining viable capture basin for control problem in presence of uncertainty. We first recall the concepts of viability theory which allow to develop numerical methods for computing viable capture basin for control problems and guaranteed control problems. Recent developments of option pricing in the framework of dynamical games with constraints lead to the formulation of guaranteed valuation in terms of guaranteed viable-capture basin of a dynamical game. As an application we show how the viability/capturability algorithm evaluates and manages portfolios. Regarding viability/capturability issues, stochastic control is a particular use of tychastic control. We replace the standard translation of uncertainty by stochastic control problem by tychastic ones and the concept of stochastic viability by the one of guaranteed viability kernel. Considering the Cox–Rubinstein model, we extend algorithms for hedging portfolios in the presence of transaction costs and dividends using recent developments on hybrid calculus.

This paper deals with inertia functions in control theory introduced in Aubin, Bernardo and Saint-Pierre (2004, 2005) and their adaptation to dynamical games. The inertia function associates with any initial state-control pair the smallest of the worst norms over time of the velocities of the controls regulating viable evolutions. For tychastic systems (parameterized systems where the parameters are tyches, disturbances, perturbations, etc.), the palicinesia of a tyche measure the worst norm over time of the velocities of the tyches. The palicinesia function is the largest palicinesia threshold c such that all evolutions with palicinesia smaller than or equal to c are viable. For dynamical games where one parameter is the control and the other one is a tyche (games against nature or robust control), we define the guaranteed inertia function associated with any initial state-control-tyche triple the best of the worst of the norms of the velocities of the controls and of the tyches and study their properties. Viability Characterizations and Hamilton-Jacobi equations of which these inertia and palicinesia functions are solutions are provided.

In this paper, we prove necessary and sufficient conditions for the viability for an impulsive stochastic functional differential inclusion driven by a fractional Brownian motion. The viable property is of interest since it reflects the stability of the model under consideration. The fractional Brownian motion provides a memory effect to the model. Whereas, the appearance of the impulsive factor introduces jumps to the solutions and is new to the analysis of this type. Hence our results are new even in the special case of stochastic differential equation setting.

The low-intensity ultrasound effects on MCF7 (human breast adenocarcinoma) and MCF10A (healthy breast cells) have been investigated at different sonication protocol to probe the effectiveness and the selectivity of the ultrasound (US) treatment and to understand the implications between cell mortality, biomechanical interactions and cell elastic modulus. Experiments performed at fixed and variable frequency demonstrated the effectiveness of some protocols in killing carcinogenic cells and the healthy cells insensitivity. Variation of elastic properties of MCF7 cells exposed to US under varying sonication conditions was examined. Sonication was carried out at fixed frequency (as it is usually done in therapy protocols), between 400kHz and 620kHz, following two protocols: (i) at fixed power output; (ii) at fixed voltage of the US generator. Evolution of cell stiffness during the US treatment was monitored via atomic force spectroscopy (AFS). It was found that cell mortality has a similar trend of variation with respect to sonication frequency regardless of the way specimens are exposed to US. Mechanical properties do not show a uniform trend with respect to frequency, but variations of Young’s modulus are more marked near the very low (400–480) kHz or very high frequencies (580–620) kHz. The observed variations may be related to mechanical interactions occurring in the cell culture, suggesting a primacy of the environment on other factors.

This review examines 43 recent papers about factors behind success and failure of innovative projects. Nine out of the 43 papers report a larger number of possible causes for success or failure and provide some rank ordering. Analyzing these rankings we find that the nine studies have a significant degree of similarity among the ten highest-ranking success factors; however, there is little similarity among lower ranking factors. The various studies remain either inconsistent or inconclusive with respect to factors such as strength of competition, R&D intensity, the degree to which a project is "innovative" or "technologically advanced" and top management support. Agreement exists, however, about the positive impact on innovative success of factors such as firm culture, experience with innovation, the multidisciplinary character of the R&D team and explicit recognition of the collective character of the innovation process or the advantages of the matrix organization.

Primary agricultural cooperative societies (PACSs) are the bases of cooperative credit structure in India. The cooperative credit structure functioning in Maharashtra state has three tiers. The main function of the PACSs is to provide short- and medium-term credit to its members. PACSs play a vital role in the socio-economic development of its members. Finance is the key to all types of activities. The efficient management of any society depends on the efficient management of finance. PACSs being financial intermediaries provide financial service with the objective of growth and profit. In the era of globalisation, PACSs face a different type of challenge which raises questions about the viability and sustainability of PACSs. A low resource base has been a major constraint in the effective functioning of PACSs. Financial stability has a direct bearing on the deposit mobilisation and overdue reduction. Limited resources result in low business activity. Limited resources, an increase in nonperforming asset, low recovery, overdue, lack of finance and lack of diversification have affected the viability of primary agricultural societies. Besides providing agriculture credit, some PACSs in Pune District are engaged in diversified activities. The PACSs that have diversified their business are more viable and sustain better than non-diversified societies. This chapter reports the viability analysis of selected PACSs in the Pune District. Multi-stage sampling technique was used. The primary and secondary data were mixed together. Primary data were collected with the help of specially designed schedules by conducting interviews, and secondary data were collected from different published sources and annual reports of PACSs. The study concludes that, as a result of the diversification, Talegoan Dhamdhere PACS in Shirur Block is potentially viable as compared to the Bhairawnath Kasarsai PACS in Mulshi Block of Pune District.

Developmental time is a trait of great relevance to fitness in all organisms. In holometabolous species that occupy ephemeral habitat, like Drosophila melanogaster, the impact of developmental time upon fitness is further exaggerated. We explored the trade-offs surrounding developmental time by selecting 10 independent populations from two distantly related selection treatments (CB_1-5 and CO_1-5) for faster development. After 125 generations, the resulting accelerated populations (ACB_1-5 and ACO_1-5) displayed net selection responses for development time of -33.4 hours (or 15%) for ACB and -38.6 hours (or 17%) for ACO. Since most of the change in egg-to-adult developmental time was accounted for by changes in larval duration, the “accelerated” larvae were estimated to develop 25-30% faster than their control/ancestor populations. The responses of ACB and ACO lines were remarkably parallel, despite being founded from populations evolved independently for more than 300 generations. On average, these “A” populations developed from egg to adult in less than eight days and produced fertile eggs less than 24 hours after emerging. Accelerated populations showed no change in larval feeding rate, but a reduction in pupation height, the latter being a trait relating to larval energetic expenditure in wandering prior to pupation. This experiment demonstrates the existence of a negative evolutionary correlation between preadult developmental time and viability, as accelerated populations experienced a severe cost in preadult survivorship. In the final assay generation, viability of accelerated treatments had declined by more than 10%, on average. A diallel cross demonstrated that the loss of viability in the ACO lines was not due to inbreeding depression. These results suggest the existence of a rapid development syndrome, in which the fitness benefits of fast development are balanced by fitness costs resulting from reduced preadult survivorship, marginal larval storage of metabolites, and reduced adult size.

Ralstonia solanacearum biovar (bv) 2 causes bacterial wilt and potato brown rot in solanaceous plants in temperate areas. The pathogen is able to persist in the environment, where it is frequently disseminated by watercourses. In these habitats, the effect of long-term oligotrophy on its survival remains to be ascertained. On that purpose river water microcosms were inoculated with R. solanacearum bv 2, incubated at 24°C and monitored for total, viable and culturable bacterial cell numbers up to four years. Within the first year, R. solanacearum bv 2 populations remained roughly constant in the initial levels. Then and until the fourth year, total counts slowly increased, while viability slightly declined and culturability decreased to a greater extent, pointing out a proportion of the bacterial populations entering the viable but non-culturable state. As cells in this state are not detected by cultivation-based methods, they represent a new challenge in designing strategies for control of the bacterial wilt disease.

Doxorubicin (DOXO), an anthracycline antibiotic, is a potent anticancer agent with severe toxic side-effects that have been attributed to its ability to generate free radicals (ROS), particularly in mitochondria. In this study, a prokaryotic organism, Salmonella typhimurium, was used to evaluate the effect of the drug on ROS-scavenging enzymes, catalase (CAT) and superoxide dismutase (SOD) activity, and on cell growth and viability. Increasing DOXO concentrations in the culture medium led to increasingly prolonged lag period, reduced growth rate and cell viability, and inhibition of SOD and CAT activity. SOD activity dropped to 66% of the control value in cells grown with 1 µg/ml DOXO and to 34% and 28% in cells grown with 150 and 300 µg/ml DOXO. CAT activity decreased progressively from 93% in 1 µg/ml DOXO to 30% in 150 µg/ml DOXO and was undetectable in 300 µg/ml. Growth in the presence of DOXO led to alterations in cytokinesis, as seen upon examination of cells under fluorescence microscope.

Viable sets in multi-valued dynamics, generated by finite families of mappings, are considered. In the case of affine Iterated Function Systems, satisfying a generalized cone condition, the existence of compact viable sets is stated, and some topological characteristics of these sets are given.

The extended distribution of L. monocytogenes in the environment and its ability to persist in food-processing environments cause the frequent contamination of foods, which represents the main source of human infection. Our objective was to assess the effect of chlorine water treatment on L. monocytogenes and to study this organism's survival strategies in chlorinated water.

RNA content, 16S rRNA (FISH), DNA content (16S rDNA and hlyA gene), culturability and substrate responsiveness combined with FISH detection (DVC-FISH assay) were assessed. L. monocytogenes cell culturability was lost after 2h in drinking water with 0.16 and 1 mg/L of free chlorine. Viability was conserved for more than 16 hours at minor chlorine concentrations. Both, the 16S rDNA gene amplicon and the hlyA fragment, specifics for L. monocytogenes, were detected after a 24-hour chlorine exposure. 16S RNA levels were constant during chlorine treatment, thus chlorine-damage of bacteria is unlikely to involve ribosome degradation. Combinied modified DVC and FISH techniques can rapidly and specifically detect and identify viable L. monocytogenes cells in water samples. Some normal disinfection practices used in drinking water treatment (free chlorine lower than 0.2 mg/L) proved to be inadequate at short time of exposition to control this organism, as it could survive in VBNC state, what can become a public health risk.