Output feedback tracking of ships

Abstract-In this brief, we consider output feedback tracking of ships with position and orientation measurements only. Ship dynamics are highly nonlinear, and for tracking control, as opposed to dynamic positioning, these nonlinearities have to be taken into account in the control design. We propose an observer-controller scheme which takes into account the complete ship dynamics, including Coriolis and centripetal forces and nonlinear damping, and results in a semi-globally uniformly stable closed-loop system. Furthermore, a gain tuning procedure for the observer-controller scheme is developed. Experimental results are presented where the observer-controller scheme is implemented onboard a Froude scaled 1:70 model supply ship. The experimentally obtained results are compared with simulation results under ideal conditions and both support the theoretical results on semi-global exponential stability of the closed-loop system

Detection and localization of early- and late-stage cancers using platelet RNA

Cancer patients benefit from early tumor detection since treatment outcomes are more favorable for less advanced cancers. Platelets are involved in cancer progression and are considered a promising biosource for cancer detection, as they alter their RNA content upon local and systemic cues. We show that tumor-educated platelet (TEP) RNA-based blood tests enable the detection of 18 cancer types. With 99% specificity in asymptomatic controls, thromboSeq correctly detected the presence of cancer in two-thirds of 1,096 blood samples from stage I–IV cancer patients and in half of 352 stage I–III tumors. Symptomatic controls, including inflammatory and cardiovascular diseases, and benign tumors had increased false-positive test results with an average specificity of 78%. Moreover, thromboSeq determined the tumor site of origin in five different tumor types correctly in over 80% of the cancer patients. These results highlight the potential properties of TEP-derived RNA panels to supplement current approaches for blood-based cancer screening

A case of legionellosis during treatment with a TNFα antagonist

We report a patient with Legionella pneumophila pneumonia after infliximab therapy for rheumatoid arthritis. Arguments are discussed for an emerging incidence of infections with intracellular microorganisms, granulomatous and non-granulomatous, in patients having received anti-TNFα therapy. These discussions consist of clinical and epidemiological data, experimental data in animals, theoretical evidence, and we provide a possible pathogenetic mechanism

Output feedback tracking of ships

In this paper we consider output feedback tracking of ships with position and orientation measurements only. Ship dynamics are highly nonlinear, and for tracking control, as opposed to dynamic positioning, these nonlinearities have to be taken into account in the control design. We propose an observer-controller scheme which takes into account the complete ship dynamics, including Coriolis and centripetal forces and nonlinear damping, and prove that the closed-loop system is semi-globally uniformly stable. Furthermore, a gain tuning procedure for the observer controller scheme is developed. Experimental results are presented where the observer-controller scheme is implemented onboard a Froude scaled 1:70 model supply ship. The experimentally obtained results are compared with simulation results under ideal conditions and both support the theoretical results on semi-global exponential stability of the closed-loop system

Output feedback tracking of ships

In this paper we consider output feedback tracking of ships withposition and orientation measurements only. Ship dynamics are highlynonlinear, and for tracking control, as opposed to dynamic positioning,these nonlinearities have to be taken into account in the controldesign. We propose an observer-controller scheme which takes intoaccount the complete ship dynamics, including Coriolis and centripetalforces and nonlinear damping, and results in a semi-globallyuniformly stable closed-loop system.Furthermore, a gain tuning procedure forthe observer-controller scheme is developed.Experimental results are presented where the observer-controller schemeis implemented onboard a Froude scaled 1:70 model supply ship. Theexperimentally obtained results are compared with simulation resultsunder ideal conditions and both support the theoretical results onsemi-global exponential stability of the closed-loop system

Feedback regulation between atypical E2Fs and APC/C-Cdh1 coordinates cell cycle progression

E2F transcription factors control the oscillating expression pattern of multiple target genes during the cell cycle. Activator E2Fs, E2F1-3, induce an upswing of E2F targets, which is essential for the G1-to-S phase transition, whereas atypical E2Fs, E2F7 and E2F8, mediate a downswing of the same targets during late S, G2, and M phases. Expression of atypical E2Fs is induced by E2F1-3, but it is unknown how atypical E2Fs are inactivated in a timely manner. Here, we demonstrate that E2F7 and E2F8 are substrates of the anaphase-promoting complex/cyclosome (APC/C). Removal of CDH1, or mutating the CDH1-interacting KEN boxes, stabilized E2F7/8 from anaphase onwards and during G1. Expressing KEN mutant E2F7 during G1 impairs S phase entry and eventually results in cell death. Furthermore, we show that E2F8, but not E2F7, interacts also with APC/C-Cdc20. Importantly, atypical E2Fs can activate APC/C-Cdh1 by repressing its inhibitors cyclin A, cyclin E, and Emi1. In conclusion, we discovered a feedback loop between atypical E2Fs and APC/C-Cdh1, which ensures balanced expression of cell cycle genes and normal cell cycle progression