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Lipids are in high demand in food production, nutritional supplements, detergents, lubricants, and biofuels. Different oil seeds produced from plants are conventionally extracted to yield lipids. With increasing population and reduced availability of cultivable land, conventional methods of producing lipids alone will not satisfy increasing demand. Lipids produced using different microbial sources are considered as sustainable alternative to plant derived lipids. Various microorganisms belonging to the genera of algae, bacteria, yeast, fungi, or marine-derived microorganisms such as thraustochytrids possess the ability to accumulate lipids in their cells. A variety of microbial production technologies are being used to cultivate these organisms under specific conditions using agricultural residues as carbon source to be cost competitive with plant derived lipids. Microbial oils, also known as single cell oils, have many advantages when compared with plant derived lipids, such as shorter life cycle, less labor required, season and climate independence, no use of arable land and ease of scale-up. In this chapter we compare the lipids derived from plants and different microorganisms. We also highlight various analytical techniques that are being used to characterize the lipids produced in oleaginous organisms and their applications in various processes.

Lipids are in high demand in food production, nutritional supplements, detergents, lubricants, and biofuels. Different oil seeds produced from plants are conventionally extracted to yield lipids. With increasing population and reduced availability of cultivable land, conventional methods of producing lipids alone will not satisfy increasing demand. Lipids produced using different microbial sources are considered as sustainable alternative to plant derived lipids. Various microorganisms belonging to the genera of algae, bacteria, yeast, fungi, or marine-derived microorganisms such as thraustochytrids possess the ability to accumulate lipids in their cells. A variety of microbial production technologies are being used to cultivate these organisms under specific conditions using agricultural residues as carbon source to be cost competitive with plant derived lipids. Microbial oils, also known as single cell oils, have many advantages when compared with plant derived lipids, such as shorter life cycle, less labor required, season and climate independence, no use of arable land and ease of scale-up. In this chapter we compare the lipids derived from plants and different microorganisms. We also highlight various analytical techniques that are being used to characterize the lipids produced in oleaginous organisms and their applications in various processes.

MINI Irene is the Flight Demonstrator of IRENE, a new-concept capsule with a variable geometry, originally conceived by ASI to widen the range of available platforms to retrieve payloads and/or data from low Earth orbit. This paper, after a short introduction of the patented IRENE deployable heat shield concept and benefits, shows the ongoing activities that will lead to the sub-orbital flight. The description is focused on the structural activities, both numerical and experimental), and on the avionic systems.

The radiometer on-board the Odin satellite comprises four different sub-mm receivers covering the 486 - 581 GHz frequency range and one fixed frequency 119 GHz receiver. Two auto-correlators and one acousto-optical spectrometer serve as backends. This article gives an overview over the processing of the data delivered by these instruments and discusses calibration issues.

The Sub-millimetre and Millimetre Radiometer (SMR) is the main instrument on the Swedish, Canadian, Finnish and French spacecraft Odin. It consists of a 1.1 metre diameter telescope with four tuneable heterodyne receivers covering the ranges 486-504 GHz and 541-581 GHz, and one fixed at 118.75 GHz together with backends that provide spectral resolution from 150 kHz to 1 MHz. This Letter describes the Odin radiometer, its operation and performance with the data processing and calibration described in Paper II.

Aim To evaluate the rate of organ donation after brain death in 2 tertiary care medical centers of a Romanian city, the reasons for donation exclusion (donors or organs), and identification of potential strategies for improvement. Material and Methods The study retrospectively evaluated potential organ donors with brain death (BD) who were identified between January 2006 and June 2009 in an university city of Romania. The potential donors were considered patients with severe intracranial pathology and clinical signs of brain death who were reported to the regional transplant team. The BD declaration was completed according to the Law of Transplant Procurement and Management in Romania: clinical signs of brain stem death, apnea test, and flat EEG, criteria that must be fulfilled twice at a 6 hour interval. According to Romanian law, family consent is mandatory for organ harvesting. Results The study included 35 potential donors, of whom 22 had a declaration of BD. Failure of potential donors to be declared BD was caused by positive viral serology (n = 7), improvement in clinical status (n = 2), sudden cardiac arrest (n = 2), and refusal of physician in charge (n = 2). Among the 22 with a BD declaration, organ harvesting was performed in only 12 cases due to family refusal (n = 10). In 4 cases the planned organ harvesting was aborted owing to unexpected intraoperative findings. Discussion Factors that generate the low rate of organ procurement include local organizational particularities, a high rate of viral infections, poor education, (both of lay persons and of medical personnel), restrictive criteria for BD declaration and the mandatory need for family approval. Conclusion The rate of donation in this university city of Romania is still low. Several strategies have been identified to improve the rate: better identification of potential donors, better management, and education of the public and of health care personnel.

Introduction. In November 2007, a legislative initiative regarding the presumed consent for organ donation was proposed for parliamentary debate in Romania and was followed by public debate. The study aimed to asses public opinions expressed in the Romanian media. Materials and Methods. An Internet search was made. The pro and con reasons, the affiliation of parts involved in the debate and suggested future direction of action were identified. Results. The Internet search had 8572 results. The parts involved in the pro and con debate consisted of governmental structures, physicians, ethicists, politicians, media, religious authorities, nongovernmental associations, and lay persons. The main pros were the low rate of organ donation and the long waiting lists, enhancement of organ procurement, avoidance of wasting valuable organs, avoiding responsibility, and the stress imposed to the family in giving the donation consent, humanitarian purposes (saving lives), going along with the scientific progress, and less bureaucracy. The main cons were an unethical issue, violation of human rights, denial of brain death, unethical advantage of public ignorance, unethical use of underprivileged people, little results in terms of organ procurement, but huge negative effects on public opinion, public mistrust in transplant programs and impossibility of refusal identification due to particularities of the Romanian medical system. Conclusion. The con opinions prevailed. For the moment, Romania seems to be unprepared to accept presumed consent. A future change in public perception regarding organ transplantation may modify the terms of a public debate.

Multicast protocols must often provide a given property on the order in which messages are delivered. This delivery order may be consistent with local dependences between messages or with causal dependences. A local delivery is defined according to the emitting order observed at the same process source. A causal delivery is defined according to the causal relations observed between different emitting events. If an arbitrary delivery order is applied (when there are no particular dependences) the multicast is said to be totally ordered. In this paper we study totally and causally ordered multicast protocols i.e. multicast protocols that guarantee a total order conforming with the causal dependences. We propose a new method that begins to build a total order to obtain a causal and total multicast, when all current methods propose to build first a causal order then a total order (developed using the services of this causal layer).This new approach results from a formal study of ordering properties. In the first main result we show that a broadcast that guarantees a local and total order also provides a causal broadcast. Then we show that a multicast protocol that guarantees a local and a total order with additional constraints is also a causal and total multicast. This result makes no assumption about structure of overlapping groups. We finally develop the scheme of a multicast protocol using a centralized server of order. This solution is efficient in terms of messages and delay for a small number of sites. It allows all types of messages (unicast, multicast, broadcast) to mix while getting a causal and total ordering.

A new solution is given for the steady-state probability computation of closed synchronized queuing networks. A closed synchronized queuing network is a particular Markov stochastic Petri net (a bounded and monovaluated Petri net with a strongly connected reachability graph and constant firing rates independent of markings). It is shown that the steady-state probability distribution can be expressed using matrix products. The results generalize the Gordon-Newell theorem. The solution is similar to the Gordon-Newell product form using matrix and vectors instead of scalars. A prototype solver developed from this result is presented. >

A new solution is presented for the steady-state probability computing of closed synchronized queuing networks. A closed synchronized queuing network is a particular Markov stochastic Petri net (bounded and monovaluated Petri net with a strongly connected reachability graph and constant firing rates independent of markings). The authors show that the steady-state probability distribution can be expressed using matrix products. The results generalize the Gordon-Newell theorem. The solution is similar to the Gordon-Newell product form solution using a matrix and vectors instead of scalars. A prototype solver developed from the preceding result is presented. >

Distributed recursive waves, a distributed programming scheme based on a procedure that calls n (or none) concurrent executions of itself, is defined. Three kinds of recursive waves (sequential, based on a tree, based on a flooding) and the example of a distributed recursive termination, respectively, are presented. Distributed recursive programming provides a natural style for writing distributed algorithms. It does not support the overhead drawback of the centralized computer recursivity. Solutions to distributed problems using the message passing wave approach or the distributed iteration scheme can also be expressed in the distributed recursive approach with the same message complexity. >

Probabilistic validation is an approach for the validation of highly dependable and complex systems. It relies on a partial analysis on a system model and tries to prove that the failed event occurrences has a sufficiently low probability. We define a probabilistic validation method using worst event driven and an importance sampling simulation. The system which must be validated is modeled by a stochastic Petri net. An efficient simulation of the net must be able to sample complex and improbable trajectories which eventually reach critical markings. Two problems have to be solved. The sequence of transition firings which may lead to critical markings must be characterized ad the Petri net level. The second problem is to sample these sequences and to build an accurate estimate of the incorrect behavior probability. We discuss several simulation algorithms in the Markovian and non-Markovian cases. We show the effectiveness of these techniques on the validation of several examples. >

A method to estimate the value of remote clocks in distributed systems is proposed. The method is able to deal with isotropic and anisotropic networks and includes a way to detect performance failures on single exchanges. It uses a statistical approach to estimate the relative drift of clocks and a round trip clock reading protocol to compute the offset. A good precision can be attained and maintained without exchanging too many specific extra messages. Numerical results obtained from a discrete event simulation are presented. >

This paper presents the software tool RDPS. The first application of RDPS is the validation of synchronized systems modelled by Petri nets. Petri nets are described using a programming language (DEOL). RDPS computes the invariants of the net, generates the reachability graph, and analyzes several properties of the graph. The second application is the evaluation of performance or dependability parameters using stochastic Petri net theory. The user can define various random variables associated with the performance or dependability parameters of a system. RDPS computes steady state or transient moments of these variables. The paper presents an example of a practical dependability study of a complex fault-tolerant system.

This paper presents the analysis of Markov stochastic Petri nets having one unbounded place. These nets represent queues the arrival and departure of customers of which can be grouped and depend on a finite homogeneous Markov process. In the first section we give a formal definition of these nets, called C-Q nets (complex-queue nets), and we state some qualitative properties of such nets (particularly we state that the reachability graph is composed by an infinite sequence of isomorphic subgraphs). In the second section we give a complete classification of ergodic properties of C-Q nets. The Markov process associated with the marking are transient, null recurrent, and positive recurrent, according to the sign of the scalar quantity C"1, N"m"a"x (where C"1 is the incidence vector of the unbounded place p"1, N"m"a"x is the maximal expected firing rate of transitions of the net). The third section is devoted to the computation of the steady-state probabilities of C-Q nets. Because the generator of the marking process is a quasi-birth-and-death matrix, we recall the results for such processes (matrix geometric solution). We present the solution based on the generalized eigenvalues. The particular structure of the generator associated to a C-Q net induces a third method to compute the steady-state probabilities that are more efficient for grouped arrival and departure.

A necessary and sufficient ergodicity condition for complex open queueing systems is given. The queueing networks considered belong to a particular class of unbounded Markov stochastic Petri nets. These systems can include synchronization features like fork and join arrivals and departures, and feedback between behavior of different queues. Grouped and correlated arrivals and departures are also allowed. An example and a proof of the ergodicity results are presented. >

The introduction of fluidbed technology in processing soybeans is discussed. Particular emphasis is given to energy and investment savings which are most significant with the newly developed EW-dehulling-conditioning process.