Genetic networks with canalyzing Boolean rules are always stable

We determine stability and attractor properties of random Boolean genetic network models with canalyzing rules for a variety of architectures. For all power law, exponential, and flat in-degree distributions, we find that the networks are dynamically stable. Furthermore, for architectures with few inputs per node, the dynamics of the networks is close to critical. In addition, the fraction of genes that are active decreases with the number of inputs per node. These results are based upon investigating ensembles of networks using analytical methods. Also, for different in-degree distributions, the numbers of fixed points and cycles are calculated, with results intuitively consistent with stability analysis; fewer inputs per node implies more cycles, and vice versa. There are hints that genetic networks acquire broader degree distributions with evolution, and hence our results indicate that for single cells, the dynamics should become more stable with evolution. However, such an effect is very likely compensated for by multicellular dynamics, because one expects less stability when interactions among cells are included. We verify this by simulations of a simple model for interactions among cells.Comment: Final version available through PNAS open access at http://www.pnas.org/cgi/content/abstract/0407783101v

Pre-existing disease: the most important factor for health related quality of life long-term after critical illness: a prospective, longitudinal, multicentre trial

Introduction The aim of the present multicenter study was to assess long term (36 months) health related quality of life in patients after critical illness, compare ICU survivors health related quality of life to that of the general population and examine the impact of pre-existing disease and factors related to ICU care on health related quality of life. Methods Prospective, longitudinal, multicentre trial in three combined medical and surgical intensive care units of one university and two general hospitals in Sweden. By mailed questionnaires, health related quality of life was assessed at 6, 12, 24 and 36 months after the stay in ICU by EQ-5D and SF-36, and information of pre-existing disease was collected at the 6 months measure. ICU related factors were obtained from the local ICU database. Comorbidity and health related quality of life (EQ-5D; SF-36) was examined in the reference group. Among the 5306 patients admitted, 1663 were considered eligible (>24 hrs in the intensive care unit, and age ≥ 18 yrs, and alive 6 months after discharge). At the 6 month measure 980 (59%) patients answered the questionnaire. Of these 739 (75%) also answered at 12 month, 595 (61%) at 24 month, and 478 (47%) answered at the 36 month measure. As reference group, a random sample (n = 6093) of people from the uptake area of the hospitals were used in which concurrent disease was assessed and adjusted for. Results Only small improvements were recorded in health related quality of life up to 36 months after ICU admission. The majority of the reduction in health related quality of life after care in the ICU was related to the health related quality of life effects of pre-existing diseases. No significant effect on the long-term health related quality of life by any of the ICU-related factors was discernible. Conclusions A large proportion of the reduction in the health related quality of life after being in the ICU is attributable to pre-existing disease. The importance of the effect of pre-existing disease is further supported by the small, long term increment in the health related quality of life after treatment in the ICU. The reliability of the conclusions is supported by the size of the study populations and the long follow-up period.

AHAA- Agile, Hybrid Assessment Method for Automotive, Safety Critical SMEs

The need for software is increasingly growing in the automotive industry. Software development projects are, however, often troubled by time and budget overruns, resulting in systems that do not fulfill customer requirements. Both research and industry lack strategies to combine reducing the long software development lifecycles (as required by time-to-market demands) with increasing the quality of the software developed. Software process improvement (SPI) provides the first step in the move towards software quality, and assessments are a vital part of this process. Unfortunately, software process assessments are often expensive and time consuming. Additionally, they often provide companies with a long list of issues without providing realistic suggestions. The goal of this paper is to describe a new low-overhead assessment method that has been designed specifically for small-to-medium-sized (SMEs) organisations wishing to be automotive software suppliers. This assessment method integrates the structured-ness of the plan-driven SPI models of Capability Maturity Model Integration (CMMI) and Automotive SPICETM with the flexibleness of agile practices

Listeria pathogenesis and molecular virulence determinants

The gram-positive bacterium Listeria monocytogenes is the causative agent of listeriosis, a highly fatal opportunistic foodborne infection. Pregnant women, neonates, the elderly, and debilitated or immunocompromised patients in general are predominantly affected, although the disease can also develop in normal individuals. Clinical manifestations of invasive listeriosis are usually severe and include abortion, sepsis, and meningoencephalitis. Listeriosis can also manifest as a febrile gastroenteritis syndrome. In addition to humans, L. monocytogenes affects many vertebrate species, including birds. Listeria ivanovii, a second pathogenic species of the genus, is specific for ruminants. Our current view of the pathophysiology of listeriosis derives largely from studies with the mouse infection model. Pathogenic listeriae enter the host primarily through the intestine. The liver is thought to be their first target organ after intestinal translocation. In the liver, listeriae actively multiply until the infection is controlled by a cell-mediated immune response. This initial, subclinical step of listeriosis is thought to be common due to the frequent presence of pathogenic L. monocytogenes in food. In normal indivuals, the continual exposure to listerial antigens probably contributes to the maintenance of anti-Listeria memory T cells. However, in debilitated and immunocompromised patients, the unrestricted proliferation of listeriae in the liver may result in prolonged low-level bacteremia, leading to invasion of the preferred secondary target organs (the brain and the gravid uterus) and to overt clinical disease. L. monocytogenes and L. ivanovii are facultative intracellular parasites able to survive in macrophages and to invade a variety of normally nonphagocytic cells, such as epithelial cells, hepatocytes, and endothelial cells. In all these cell types, pathogenic listeriae go through an intracellular life cycle involving early escape from the phagocytic vacuole, rapid intracytoplasmic multiplication, bacterially induced actin-based motility, and direct spread to neighboring cells, in which they reinitiate the cycle. In this way, listeriae disseminate in host tissues sheltered from the humoral arm of the immune system. Over the last 15 years, a number of virulence factors involved in key steps of this intracellular life cycle have been identified. This review describes in detail the molecular determinants of Listeria virulence and their mechanism of action and summarizes the current knowledge on the pathophysiology of listeriosis and the cell biology and host cell responses to Listeria infection. This article provides an updated perspective of the development of our understanding of Listeria pathogenesis from the first molecular genetic analyses of virulence mechanisms reported in 1985 until the start of the genomic era of Listeria research

Generativ AI som samskapare i framställningen av bilder

Generative AI systems for image-creation have taken a giant leap technologically in the last few years, creating opportunities for users and introducing new areas of research for the scientific community. New implementations for these technologies are discovered regularly and due to the complex nature of AI, there is an ongoing discussion among researchers on whether generative AI is yet another tool, or if there is potential for the technology to be something more. The aim of this study is to explore the nuances and complexity of co-creation with generative AI, using post-human and post-anthropocentric perspectives that consider human agencies as entangled with machine agency. To understand whether human-AI co-creation is sustainable and valuable as an activity, a netnographic study was conducted to explore the different aspects of user interaction. Among the most relevant of these aspects were the system limitations, dataset limitations, prompting, user goals and user procedures. The study found that the current limitations to the generative AI systems were too significant for the systems to display a high amount of machine agency. This ultimately pointed to human-AI co-creation being non-sustainable and non-valuable as an activity, but the resultsand following discussion also suggest how we can move on overcoming these limitations.Generativa AI-system för bildskapande har teknologiskt tagit ett stort kliv framåt de senaste åren, detta har lett till möjligheter för användare och det har introducerat nya forskningsområden för forskarvärlden. Nya tillämpningar för dessa teknologier upptäcks regelbundet. På grund av den komplexa naturen hos AI så pågår en diskussion bland forskare gällande huruvida generativ AI är ett nytt verktyg, eller om det finns potential för teknologin att vara något mer. Denna studies mål är att undersöka nyanserna och komplexiteten hos samskapande med generativ AI, genom att använda post-humanistiska och post-antropocentriska perspektiv som betraktar mänsklig ”agency” som sammanflätad med maskiners ”agency”. För att förstå huruvida människa-AI-samskapande är hållbart och värdefullt så utfördes en netnografisk undersökning för att granska de olika aspekterna med användarinteraktion. Bland de mest relevanta av dessa aspekter var systembegränsningarna, datasetsbegränsningarna, promptning, användarmål och användarprocedurer. Undersökningen visade att de nuvarande begränsningarna hos generativa AI-system är för stora för att systemen skulle kunna uppvisa en hög grad ”maskin-agens”. Detta pekade i slutändan mot att människa-AI-samskapande är ohållbart och icke värdefullt som en aktivitet. Men resultaten och den följande diskussionen antyder också hur vi kan gå vidare med att övervinna dessa begränsningar

Generativ AI som samskapare i framställningen av bilder

Generative AI systems for image-creation have taken a giant leap technologically in the last few years, creating opportunities for users and introducing new areas of research for the scientific community. New implementations for these technologies are discovered regularly and due to the complex nature of AI, there is an ongoing discussion among researchers on whether generative AI is yet another tool, or if there is potential for the technology to be something more. The aim of this study is to explore the nuances and complexity of co-creation with generative AI, using post-human and post-anthropocentric perspectives that consider human agencies as entangled with machine agency. To understand whether human-AI co-creation is sustainable and valuable as an activity, a netnographic study was conducted to explore the different aspects of user interaction. Among the most relevant of these aspects were the system limitations, dataset limitations, prompting, user goals and user procedures. The study found that the current limitations to the generative AI systems were too significant for the systems to display a high amount of machine agency. This ultimately pointed to human-AI co-creation being non-sustainable and non-valuable as an activity, but the resultsand following discussion also suggest how we can move on overcoming these limitations.Generativa AI-system för bildskapande har teknologiskt tagit ett stort kliv framåt de senaste åren, detta har lett till möjligheter för användare och det har introducerat nya forskningsområden för forskarvärlden. Nya tillämpningar för dessa teknologier upptäcks regelbundet. På grund av den komplexa naturen hos AI så pågår en diskussion bland forskare gällande huruvida generativ AI är ett nytt verktyg, eller om det finns potential för teknologin att vara något mer. Denna studies mål är att undersöka nyanserna och komplexiteten hos samskapande med generativ AI, genom att använda post-humanistiska och post-antropocentriska perspektiv som betraktar mänsklig ”agency” som sammanflätad med maskiners ”agency”. För att förstå huruvida människa-AI-samskapande är hållbart och värdefullt så utfördes en netnografisk undersökning för att granska de olika aspekterna med användarinteraktion. Bland de mest relevanta av dessa aspekter var systembegränsningarna, datasetsbegränsningarna, promptning, användarmål och användarprocedurer. Undersökningen visade att de nuvarande begränsningarna hos generativa AI-system är för stora för att systemen skulle kunna uppvisa en hög grad ”maskin-agens”. Detta pekade i slutändan mot att människa-AI-samskapande är ohållbart och icke värdefullt som en aktivitet. Men resultaten och den följande diskussionen antyder också hur vi kan gå vidare med att övervinna dessa begränsningar

Konstruktion av en MMIC serie-till-parallellomvandlare på Gallium Arsenid.

A 5-bit MMIC serial to parallel converter has been designed in Gallium Arsenide. It is intended to be used together with a 5-bit True Time Delay (TTD) circuit, but it can easily be expanded into an arbitrary number of bits. The circuit has been designed with a logic style called DCFL and a 0.20 mm process (ED02AH) from OMMIC has been used to fabricate the circuit. The chip size of this 5-bit MMIC serial to parallel converter is 2.0x0.8 mm (including pads) and close to two hundred transistors are used. Due to the complexity of the transistor models the complete serial to parallel converter has not been fully simulated. However, the smaller building blocks like inverter, latch, etc. have been simulated successfully. These blocks were assembled into the complete circuit