1,405 research outputs found
Recommended from our members
Investigation into a Layered Approach to Architecting Security-Informed Safety Cases
The paper describes a layered approach to analysing safety and security in a structured way and creating a security-informed safety case. The approach is applied to a case study – a Security Gateway controlling data flow between two different security domains implemented with a separation kernel based operating system in an avionics environment. We discuss some findings from the case study, show how the approach identifies and ameliorates important interactions between safety and security and supports the development of complex assurance case structures
Recommended from our members
Security-Informed Safety Case Approach to Analysing MILS Systems
Safety cases are the development foundation for safety-critical systems and are often quite complex to understand depending on the size of the system and operational conditions. The recent advent of security aspects complicates the issues further. This paper describes an approach to analysing safety and security in a structured way and creating security-informed safety cases that provide justification of safety taking into particular consideration the impact of security. The paper includes an overview of the structured assurance case concept, a security-informed safety methodology and a layered approach to constructing cases. The approach is applied to a Security Gateway that is used to control data flow between security domains in a separation kernel based operating system in avionics environment. We show that a clear and structured way of presenting a safety case combining safety and security alleviates understanding important interactions taking into account the impact and, hence, increases safety
Complete genome sequence of Syntrophobacter fumaroxidans strain (MPOB(T)).
Syntrophobacter fumaroxidans strain MPOB(T) is the best-studied species of the genus Syntrophobacter. The species is of interest because of its anaerobic syntrophic lifestyle, its involvement in the conversion of propionate to acetate, H2 and CO2 during the overall degradation of organic matter, and its release of products that serve as substrates for other microorganisms. The strain is able to ferment fumarate in pure culture to CO2 and succinate, and is also able to grow as a sulfate reducer with propionate as an electron donor. This is the first complete genome sequence of a member of the genus Syntrophobacter and a member genus in the family Syntrophobacteraceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 4,990,251 bp long genome with its 4,098 protein-coding and 81 RNA genes is a part of the Microbial Genome Program (MGP) and the Genomes to Life (GTL) Program project
Classes of depression symptom trajectories in patients with major depression receiving a collaborative care intervention
Purpose Collaborative care is effective in improving symptoms of patients with depression. The aims of this study were to characterize symptom trajectories in patients with major depression during one year of collaborative care and to explore associations between baseline characteristics and symptom trajectories. Methods We conducted a cluster-randomized controlled trial in primary care. The collaborative care intervention comprised case management and behavioral activation. We used the Patient Health Questionnaire-9 (PHQ-9) to assess symptom severity as the primary outcome. Statistical analyses comprised latent growth mixture modeling and a hierarchical binary logistic regression model. Results We included 74 practices and 626 patients (310 intervention and 316 control recipients) at baseline. Based on a minimum of 12 measurement points for each intervention recipient, we identified two latent trajectories, which we labeled \u27fast improvers\u27 (60.5%) and \u27slow improvers\u27 (39.5%). At all measurements after baseline, \u27fast improvers\u27 presented higher PHQ mean values than \u27slow improvers\u27. At baseline, \u27fast improvers\u27 presented fewer physical conditions, higher health-related quality of life, and had made fewer suicide attempts in their history. Conclusions A notable proportion of 39.5% of patients improved only \u27slowly\u27 and probably needed more intense treatment. The third follow-up in month two could well be a sensible time to adjust treatment to support \u27slow improvers\u27. (DIPF/Orig.
Recommended from our members
Modelling road hazards and the effect on AV safety of hazardous failures
Autonomous vehicles (AV) are about to appear on our roads within the next few years. However, to achieve the final breakthrough, not only functional progress is required, but also fundamental safety questions must be solved. Among those, a question demanding special attention is the need to assess the overall safety of an AV and quantify that it is safe enough to take part in normal traffic despite its inherent imperfections. Therefore, this paper describes a probabilistic model, which allows to study how imperfections of an AV perception system and of mechanisms responsible for AV safety (e.g., Safety Monitors), can impact AV safety in the presence of road hazards. We also demonstrate how the model can be used to validate if the AV is safe enough, to understand the criticality of (perception) errors, and to identify areas/parameters that have more influence on safety than others
Quality of life after on-pump and off-pump coronary artery bypass grafting surgery
FUNDAMENTO: Técnicas de cirurgia de revascularização miocárdica (RM) sem o uso de circulação extracorpórea (CEC) possibilitou resultados operatórios com menor dano sistêmico, menor ocorrência de complicações clÃnicas, menor permanência na sala de terapia intensiva e também no tempo de internação, gerando expectativas de melhor qualidade de vida (QV) dos pacientes. OBJETIVO: Avaliar a QV em pacientes submetidos à cirurgia de revascularização com e sem CEC. MÉTODOS: Em pacientes com doença multiarterial coronariana (DAC) estável e função ventricular preservada, aplicou-se o Short-Form Health Survey (SF-36) Questionnaire antes da cirurgia e depois de 6 e 12 meses. RESULTADOS: Entre janeiro de 2002 e dezembro de 2006, foram randomizados 202 pacientes para cirurgia de RM. As caracterÃsticas demográficas clÃnicas laboratoriais e angiográficas foram semelhantes nos dois grupos. Desses pacientes, 105 foram operados sem CEC e 97 com CEC. Na evolução, 22 pacientes sofreram infarto, 29 relataram angina, um reoperou, 3 tiveram AVC e nenhum morreu. A avaliação da QV mostrou similaridade nos dois grupos em relação ao componente fÃsico e mental. Todavia, encontrou-se significativa melhora da capacidade funcional e percepção do aspecto fÃsico nos pacientes do sexo masculino. Além disso, um expressivo número de pacientes dos dois grupos retornou ao trabalho. CONCLUSÃO: Em todos os pacientes estudados, observaram-se melhora progressiva da qualidade de vida e retorno precoce ao trabalho, independentemente da técnica cirúrgica empregada. Exceto pela melhor percepção da capacidade funcional e do aspecto fÃsico experimentado pelos homens, não houve diferença estatÃstica nos resultados dos demais domÃnios alcançados pelos dois grupos estudados.BACKGROUND: Coronary artery bypass grafting techniques without using cardiopulmonary bypass (off-pump CABG) result in less systemic damage, less clinical complications, less time spent in the intensive care unit, and shorter hospital stays, thereby raising the perspective of improved quality of life (QOL) for patients. OBJECTIVE: To assess quality of life in patients who underwent on-pump and off-pump CABG. METHODS: The Short-Form Health Survey (SF-36) Questionnaire was administered to patients with stable multivessel coronary artery disease (CAD) and preserved ventricular function before and at six and 12 months after surgery. RESULTS: Between January 2002 and December 2006, a total of 202 patients were randomized to either on-pump or off-pump CABG. Demographic, clinical, laboratory, and angiographic characteristics were similar in both groups. One hundred and five patients underwent off-pump CABG and 97 underwent on-pump CABG. In the postoperative course, 22 patients had myocardial infarction, 29 reported angina, one was reoperated, and three experienced stroke. No patient died. Quality of life, as measured by the SF-36 questionnaire, was shown to be similar in both groups regarding physical and mental components. However, male patients showed a significant improvement in physical functioning and role limitations due to physical problems. Also, a large number of patients in both groups returned to work. CONCLUSION: Progressive enhancement in quality of life and early return to work were observed for all patients, regardless of the surgical technique used. Save for a greater improvement in physical functioning and role limitations due to physical problems experienced by male patients, no statistically significant differences were found in the other domains between groups
Charge Collection and Electrical Characterization of Neutron Irradiated Silicon Pad Detectors for the CMS High Granularity Calorimeter
The replacement of the existing endcap calorimeter in the Compact Muon
Solenoid (CMS) detector for the high-luminosity LHC (HL-LHC), scheduled for
2027, will be a high granularity calorimeter. It will provide detailed
position, energy, and timing information on electromagnetic and hadronic
showers in the immense pileup of the HL-LHC. The High Granularity Calorimeter
(HGCAL) will use 120-, 200-, and 300- thick silicon (Si) pad
sensors as the main active material and will sustain 1-MeV neutron equivalent
fluences up to about . In order
to address the performance degradation of the Si detectors caused by the
intense radiation environment, irradiation campaigns of test diode samples from
8-inch and 6-inch wafers were performed in two reactors. Characterization of
the electrical and charge collection properties after irradiation involved both
bulk polarities for the three sensor thicknesses. Since the Si sensors will be
operated at -30 C to reduce increasing bulk leakage current with
fluence, the charge collection investigation of 30 irradiated samples was
carried out with the infrared-TCT setup at -30 C. TCAD simulation
results at the lower fluences are in close agreement with the experimental
results and provide predictions of sensor performance for the lower fluence
regions not covered by the experimental study. All investigated sensors display
60 or higher charge collection efficiency at their respective highest
lifetime fluences when operated at 800 V, and display above 90 at the
lowest fluence, at 600 V. The collected charge close to the fluence of
exceeds 1 fC at voltages
beyond 800 V.Comment: 36 pages, 34 figure
- …