Combined Approach for Supporting the Business Process Model Lifecycle

Business processes evolve throughout their lifecycle of change. Business Process Modeling (BPM2) notations such as BPMN are used to effectively conceptualize and communicate important process characteristics to relevant stakeholders. Agent-oriented conceptual modeling notations, such as i*, effectively capture and communicate organizational context. In this paper we argue that the management of change throughout the business process model lifecycle can be more effectively supported by combining notations. In particular, we identify two potential sources of process change, one occurring within the organizational context and the other within the operational context. As such the focus in this paper is on the co-evolution of operational (BPMN) and organizational (i*) models. Our intent is to provide a way of expressing changes, which arise in one model, effectively in the other model. We present constrained development methodologies capable of guiding an analyst when reflecting changes from an i* model to a BPMN model and vice-versa

Studying the effects of galactic cosmic radiation on astro- and microbiological model systems

In-depth knowledge regarding the biological effects of the radiation field in space is required for assessing the radiation risks in space. Within the last 50 years, space technology has provided tools for transporting terrestrial life beyond this protective magnetic field in order to study in situ responses to selected conditions of space (reviewed in Horneck et al., 2010). From a biological perspective applicable to simple and complex organisms (ranging from biomolecules and microorganisms to humans) various influential physical modifications such as increased radiation exposure were experienced onboard an orbiting spacecraft in low Earth orbit (LEO), out- and inside the International Space Station (ISS), orbiting Moon or on the way to other astrobiological-interesting targets (Mars or icy moons of Saturn or Jupiter). The majority of experiments on microorganisms in space were performed using Earth-orbiting robotic spacecraft, e.g., the Russian Foton satellites (FOTON) and the European Retrievable Carrier (EURECA), or human-tended spacecraft, such as space shuttles and space stations, e.g., MIR and ISS (reviewed in Nicholson, 2009; Nicholson et al., 2009; Horneck et al., 2010)

Combining i* and BPMN for business process model lifecycle management

The premise behind ‘third wave’ Business Process Management (BPM1) is effective support for change at levels. Business Process Modeling (BPM2) notations such as BPMN are used to effectively conceptualize and communicate process configurations to relevant stakeholders. In this paper we argue that the management of change throughout the business process model lifecycle requires greater conceptual support achieved via a combination of complementary notations. As such the focus in this paper is on the co-evolution of operational (BPMN) and organizational (i*) models. Our intent is to provide a way of expressing changes, which arise in one model, effectively in the other model. We present constrained development methodologies capable of guiding an analyst when reflecting changes from an i* model to a BPMN model and vice-versa. 1 Introductio

Pulsar Birthrates from the Parkes Multibeam Survey

We investigate the pulsar birthrate from a sample of 815 nonrecycled pulsars detected by the Parkes multibeam survey, accounting as accurately as possible for all known selection effects. We find that pulsars with magnetic fields greater than 2.5 ×1012 G account for more than half of the total birthrate in spite of comprising only about 5%-10% of the total Galactic population. While we do not find evidence for a significant population of pulsars injected into the population with spin periods of ~0.5 s, we do find that many, perhaps 40%, are born with periods in the range 0.1-0.5 s. The absolute number and birthrate of Galactic pulsars is strongly dependent on the assumed models for pulsar beaming and Galactic electron distribution. Adopting the most recent models, we find the total pulsar birthrate to be between 0.9 and 1.9 pulsars per century for 1400 MHz luminosities greater than 1 mJy kpc2, and the total Galactic population of active radio pulsars above this luminosity limit to be between 70,000 and 120,000

NEW MODELORGANISMS FOR ASTROBIOLOGY FROM MARS ANALOG ENVIRONMENTS

A selection of the core questions in astrobiology deal with the origin of life on Earth, life in extreme environments on Earth, and the search for past and present life on other celestial bodies. We are therefore searching for new model-organisms for astrobiology in extreme environments, the so-called Martian analog environments, which are similar to past and present-day Mars in some characteristics and properties (anoxic conditions, low nutrient availability, high salinity, low temperatures, etc.). At the moment we are working with three facultative anaerobic model-organisms, namely Yersinia intermedia MASE-LG-1, Buttiauxella sp. MASE-IM-9, and Salinisphaera shabanensis. These organisms are being evaluated for their tolerance to Mars relevant stress factors such as desiccation, Martian atmosphere, radiation (polychromatic / monochromatic UV; ionizing radiation), oxidizing compounds (perchlorates), and the presence of an analog Martian regolith. All these influencing factors were tested under anoxic conditions as single stresses and in combination [1, 2]. The results showed that the new model-organisms for the most part clearly survived the various stress factors, thus qualifying them as possible candidates for our future space experiment called MEXEM (Mars EXposed Extremophiles Mixture). MEXEM which will be an exposure experiment which is installed on the outside of the international space station

From Mars analogue environments to space: ground data evaluation of the survivability of Buttiauxella sp. MASE-IM-9 and Salinisphaera shabanensis

Mars analogues environments are some of the most extreme locations on Earth. Their unique combination of multiple extremes (e.g. high salinity, anoxia, and low nutrient availability) make them a valuable source of new polyextremophilic microbes in general, and for exploring the limits of life. These are seen as vital sources of information for Astrobiology, with implications for planetary protection and the search for life outside our planet. Despite this well-recognized relevance, current knowledge on the capability of (facultative) anaerobic microbes as single strains or in communities to withstand extraterrestrial conditions is still very sparse. Addressing this knowledge gap is one of the main goals of the project MEXEM (Mars EXposed Extremophiles Mixture), which is in preparation at the moment. As part of MEXEM, selected model organisms from all three domains of Life, will be exposed in a 3-month passive experiment with exposure to space conditions under anoxia followed by evaluation after their arrival back on Earth. The launch to the International Space Station is currently foreseen for 2024, and implies a series of preliminary tests and data collection on some of the selected strains. Here, we report on the survivability of Salinisphaera shabanensis, isolated from a deep-sea brine pool within the Red Sea, and of Buttiauxella sp. MASE-IM-9 isolated from a German sulphidic spring after exposure to Mars relevant stress factors (like desiccation and UV-radiation under anoxic conditions). Both organisms showed survival after anoxic desiccation for up to three months but this could be further extended by adding low amounts of artificial Mars regolith (MGS- 1S; 0.5 % wt/vol) and sucrose (0.1 M). The addition of these two components resulted in an elevation of the survival rate after desiccation of up to three orders of magnitude. Survival after desiccation could even be reproduced, if the cells were mixed, as an artificial community, before desiccation treatment. The presence of these two components also positively influenced survival after exposure to polychromatic UV (200 - 400 nm) up to 12 kJ/m2 in liquid and in a desiccated form

Ignicoccus hospitalis – understanding its extraordinary radiation tolerance and an unsolved archaeal repair system

Ignicoccus hospitalis is an obligate anaerobic, hyperthermophilic and chemolithoautotrophic archaeal microorganism that has exhibited an extraordinarily high tolerance against ionizing radiation (1). It was demonstrated by Koschnitzki, 2016 that I. hospitalis cells can remain viable after exposure to X-ray doses up to 12 kGy and it can completely repair DNA damages within one hour (2). I. hospitalis has a D10-value of ~5 kGy but it can remain metabolically active after being exposed up to 118 kGy (3). This exceptional radiotolerance is unexpected since ionizing radiation is not present in its natural environment - a submarine system of hydrothermal vents (4). Given that DNA damages induced by high temperature are similar to those induced by ionizing radiation (5), we hypothesize that the radiation tolerance of I. hospitalis is a consequence of the intrinsic biological properties it uses to cope the extreme conditions of its habitat. To unravel the mechanisms involved in the radiation tolerance of I. hospitalis, two approaches are currently being followed: exploring the intracellular-specific protection and monitoring the gene regulation of the DNA repair process. Having multiple genome copies (polyploidy) might allow microbes for genomic DNA protection, maintenance, and repair at extreme conditions (6). The possibility of polyploidy in I. hospitalis was addressed. The number of genome copies per cell under different growth stages was calculated based on the quantitation of the total DNA content and the cell density from a series of culture aliquots. It was found that during the beginning of Log phase, I. hospitalis cells have 0.85±0.35 genomes/cell, in the middle of Log phase this value doubles to 1.78±0.27 genomes/cell, and at the stationary phase it drops again to 0.59±0.37 genomes/cell. Compatible solutes have been extensively studied for their role in cellular protection against severe injuring influences like osmotic stress or heat shock, and for their function as radical scavenging molecules (7). A combination of different cultivation setups, like supra-optimal growth temperatures (92.5 – 95 ˚C) and high salinity (3 – 5 % w/v) were tested to influence the accumulation of compatible solutes. Then, desiccation survival was used as an indication of their presence within the cells. No cell survival after desiccation was detected, meaning there isn’t significant compatible solutes accumulation. An alternative intracellular protection mechanism in some microorganisms is based on the intracellular manganese/iron (Mn/Fe) ratio. It has been reported that Deinococcus radiodurans accumulates high amounts of intracellular manganese and low levels of iron (8). The determination of intracellular content of these two transition metals is currently ongoing, and it will be measured by ICP-MS. A set of transcriptomics experiments are currently in progress in order to investigate the up-or-downregulation of genes related with DNA repair mechanisms. We will use dRNA-seq analysis to contrast different irradiation conditions with pre-selected time points during the DNA repair process and optimal conditions. This project will help to gain knowledge on the DNA repair mechanisms in Archaea, and to better understand the limits of life

Can Extreme Bacteria Teach Us About Extraterrestrial Life?

Have you ever wondered if there is life beyond Earth? Scientists have been studying this topic for a long time and believe the answer might lie in extremophilic microbes, small organisms that thrive in extreme environments. In a 2022 study, scientists took extremophilic microbes from an analogue environment, or place on Earth similar to Mars, and put them in simulated Martian conditions. After exposing them to higher ultraviolet radiation levels, low oxygen levels, a dry atmosphere, and moisture-free Mars-like soil, these microbes still were able to survive. This research is important in helping us understand if Mars can house life and give us clues into what that life might look like beyond Earth

Surviving Mars: new insights into the persistence of facultative anaerobic microbes from analogue sites

Mars analogue environments are some of the most extreme locations on Earth. Their unique combination of multiples extremes (e.g. high salinity, anoxia and low nutrient availability) make them valuable sources for finding new polyextremophilic microbes, and for exploring the limits of life. Mars, especially at its surface, is still considered to be very hostile to life but it probably possesses geological subsurface niches where the occurrence of (polyextremophilic) life is conceivable. Despite their well-recognized relevance, current knowledge on the capability of (facultative) anaerobic microbes to withstand extraterrestrial/Martian conditions, either as single strains or in communities, is still very sparse. Therefore, space experiments simulating the Martian environmental conditions by using space as a tool for astrobiological research are needed to substantiate the hypotheses of habitability of Mars. Addressing this knowledge gap is one of the main goals of the project MEXEM (Mars EXposed Extremophiles Mixture), where selected model organisms will be subjected to space for a period of 3 months. These experiments will take place on the Exobiology facility (currently under development and implementation), located outside the International Space Station. Such space experiments require a series of preliminary tests and ground data collection for the selected microbial strains. Here, we report on the survivability of Salinisphaera shabanensis and Buttiauxella sp. MASE-IM-9 after exposure to Mars-relevant stress factors (such as desiccation and ultraviolet (UV) radiation under anoxia). Both organisms showed survival after anoxic desiccation for up to 3 months but this could be further extended (nearly doubled) by adding artificial Mars regolith (MGS-1S; 0.5% wt/v) and sucrose (0.1 M). Survival after desiccation was also observed when both organisms were mixed before treatment. Mixing also positively influenced survival after exposure to polychromatic Mars-like UV radiation (200–400 nm) up to 12 kJ m−2, both in suspension and in a desiccated for