Vertical Guidance Performance Analysis of the L1–L5 Dual-Frequency GPS/WAAS User Avionics Sensor

This paper investigates the potential vertical guidance performance of global positioning system (GPS)/wide area augmentation system (WAAS) user avionics sensor when the modernized GPS and Galileo are available. This paper will first investigate the airborne receiver code noise and multipath (CNMP) confidence (σair). The σair will be the dominant factor in the availability analysis of an L1–L5 dual-frequency GPS/WAAS user avionics sensor. This paper uses the MATLAB Algorithm Availability Simulation Tool (MAAST) to determine the required values for the σair, so that an L1–L5 dual-frequency GPS/WAAS user avionics sensor can meet the vertical guidance requirements of APproach with Vertical guidance (APV) II and CATegory (CAT) I over conterminous United States (CONUS). A modified MAAST that includes the Galileo satellite constellation is used to determine under what user configurations WAAS could be an APV II system or a CAT I system over CONUS. Furthermore, this paper examines the combinations of possible improvements in signal models and the addition of Galileo to determine if GPS/WAAS user avionics sensor could achieve 10 m Vertical Alert Limit (VAL) within the service volume. Finally, this paper presents the future vertical guidance performance of GPS user avionics sensor for the United States’ WAAS, Japanese MTSAT-based satellite augmentation system (MSAS) and European geostationary navigation overlay service (EGNOS)

A Real-Time Capable Software-Defined Receiver Using GPU for Adaptive Anti-Jam GPS Sensors

Due to their weak received signal power, Global Positioning System (GPS) signals are vulnerable to radio frequency interference. Adaptive beam and null steering of the gain pattern of a GPS antenna array can significantly increase the resistance of GPS sensors to signal interference and jamming. Since adaptive array processing requires intensive computational power, beamsteering GPS receivers were usually implemented using hardware such as field-programmable gate arrays (FPGAs). However, a software implementation using general-purpose processors is much more desirable because of its flexibility and cost effectiveness. This paper presents a GPS software-defined radio (SDR) with adaptive beamsteering capability for anti-jam applications. The GPS SDR design is based on an optimized desktop parallel processing architecture using a quad-core Central Processing Unit (CPU) coupled with a new generation Graphics Processing Unit (GPU) having massively parallel processors. This GPS SDR demonstrates sufficient computational capability to support a four-element antenna array and future GPS L5 signal processing in real time. After providing the details of our design and optimization schemes for future GPU-based GPS SDR developments, the jamming resistance of our GPS SDR under synthetic wideband jamming is presented. Since the GPS SDR uses commercial-off-the-shelf hardware and processors, it can be easily adopted in civil GPS applications requiring anti-jam capabilities

The pyrrolizidine alkaloid senecionine induces CYP-dependent destruction of sinusoidal endothelial cells and cholestasis in mice

Pyrrolizidine alkaloids (PAs) are widely occurring phytotoxins which can induce severe liver damage in humans and other mammalian species by mechanisms that are not fully understood. Therefore, we investigated the development of PA hepatotoxicity in vivo, using an acutely toxic dose of the PA senecionine in mice, in combination with intravital two-photon microscopy, histology, clinical chemistry, and in vitro experiments with primary mouse hepatocytes and liver sinusoidal endothelial cells (LSECs). We observed pericentral LSEC necrosis together with elevated sinusoidal marker proteins in the serum of senecionine-treated mice and increased sinusoidal platelet aggregation in the damaged tissue regions. In vitro experiments showed no cytotoxicity to freshly isolated LSECs up to 500 µM senecionine. However, metabolic activation of senecionine by preincubation with primary mouse hepatocytes increased the cytotoxicity to cultivated LSECs with an EC50 of approximately 22 µM. The cytochrome P450 (CYP)-dependency of senecionine bioactivation was confirmed in CYP reductase-deficient mice where no PA-induced hepatotoxicity was observed. Therefore, toxic metabolites of senecionine are generated by hepatic CYPs, and may be partially released from hepatocytes leading to destruction of LSECs in the pericentral region of the liver lobules. Analysis of hepatic bile salt transport by intravital two-photon imaging revealed a delayed uptake of a fluorescent bile salt analogue from the hepatic sinusoids into hepatocytes and delayed elimination. This was accompanied by transcriptional deregulation of hepatic bile salt transporters like Abcb11 or Abcc1. In conclusion, senecionine destroys LSECs although the toxic metabolite is formed in a CYP-dependent manner in the adjacent pericentral hepatocytes.</p

Inhibition of activin-like kinase 4/5 attenuates cancer cachexia associated muscle wasting

Cancer mediated activation of the ActRIIB-ALK4/5 heterodimer by myostatin is strongly associated with muscle wasting. We investigated in vitro and in vivo the efficacy of ALK4/5 receptor blockers SB431542 and GW788388 in preventing muscle wasting, and explored synergy with IGF-I analogue LONG R3 (LR3) IGF-I. In vitro, C2C12 skeletal muscle cells were treated with vehicle, SB431542, GW788388 and LR3 IGF-I. A C26-CD2F1 cachexia model was used to induce cachexia in vivo. Mice were allocated as non-tumour bearing (NTB) or C26 tumour-bearing (C26 TB) vehicle control, treated with SB431542, LR3 IGF-I, SB431542 and LR3 IGF-I, or GW788388 (intraperitoneally or orally). In vitro, differentiation index and mean nuclei count increased using SB431542, GW788388, LR3 IGF-I. In vivo, GW788388 was superior to SB431542 in limiting loss of bodyweight, grip-strength and gastrocnemius weight. and downregulated Atrogin-1 expression comparable to NTB mice. LR3 IGF-I treatment limited loss of muscle mass, but at the expense of accelerated tumour growth. In conclusion, treatment with GW788388 prevented cancer cachexia, and downregulated associated ubiquitin ligase Atrogin-1

25th annual computational neuroscience meeting: CNS-2016

The same neuron may play different functional roles in the neural circuits to which it belongs. For example, neurons in the Tritonia pedal ganglia may participate in variable phases of the swim motor rhythms [1]. While such neuronal functional variability is likely to play a major role the delivery of the functionality of neural systems, it is difficult to study it in most nervous systems. We work on the pyloric rhythm network of the crustacean stomatogastric ganglion (STG) [2]. Typically network models of the STG treat neurons of the same functional type as a single model neuron (e.g. PD neurons), assuming the same conductance parameters for these neurons and implying their synchronous firing [3, 4]. However, simultaneous recording of PD neurons shows differences between the timings of spikes of these neurons. This may indicate functional variability of these neurons. Here we modelled separately the two PD neurons of the STG in a multi-neuron model of the pyloric network. Our neuron models comply with known correlations between conductance parameters of ionic currents. Our results reproduce the experimental finding of increasing spike time distance between spikes originating from the two model PD neurons during their synchronised burst phase. The PD neuron with the larger calcium conductance generates its spikes before the other PD neuron. Larger potassium conductance values in the follower neuron imply longer delays between spikes, see Fig. 17.Neuromodulators change the conductance parameters of neurons and maintain the ratios of these parameters [5]. Our results show that such changes may shift the individual contribution of two PD neurons to the PD-phase of the pyloric rhythm altering their functionality within this rhythm. Our work paves the way towards an accessible experimental and computational framework for the analysis of the mechanisms and impact of functional variability of neurons within the neural circuits to which they belong

Blinde barns selvstendighet : en kvalitativ intervjuundersøkelse

Dette prosjektet har satt søkelys på hvilken bevissthet foreldre til blindfødte barn har når det gjelder utvikling av selvstendighet for barnet. Studien tar utgangspunkt i en kvalitativ forskningstilnærming. Det vil si at datainnsamlingen har foregått ved hjelp av kvalitativt forskningsintervju. Utvalget av informanter har bestått av foreldre til blinde barn som er mellom 10 og 15 år. Prosjektets resultater er presentert i fire kategorier. Kategoriene er: 1. Kompenserende teknikker og tilrettelegging 2. Læringsmessige utfordringer 3. Tid 4. Mobilitet Funnene viser at informantene har god bevissthet om kompenserende teknikker og tilrettelegginger som er nødvendig i en opplæringssituasjon for blinde barn. Funnene viser også noen utfordringer med selvstendighetsutviklingen. Dette viser seg ved at det er tendenser til at barna får mer hjelp enn nødvending i noen situasjoner. Barna har potensiale til å gjøre mer selv, men gjør det ikke på grunn av mangel på tid til å lære å være selvstendig. Mobilitetsopplæring er et område som blir beskrevet som utfordrende og viktig for å øke selvstendigheten. Samlet kan man si at foreldre har oppmerksomhet mot en bred forståelse av hva blinde barn har behov for, når de skal utvikle selvstendighet. Dette viser en kompleksitet i fagområdet. Det er vanskelig å omtale disse områdene som en frittstående del av opplæringen, men må betraktes som deler av en større helhet og tilnærming

Testing of Malting Barley - Variety Bojos.

The pilot plant and full-scale trials were made with malts from barley varieties Bojos and Tolar.The wort and beer were analysed to find out whether Tolar variety could be substitute for Bojos variety. Bojos variety had a very good wort extract, lower content of β-glucans and a perfect wort clarity. The results of Hartong VZ 45 °C, FAN and final attenuation were on the similar level as Tolar variety. Contents of fermentable sugars and dextrins in worts from Bojos and Tolar were very similar. Bojos variety proved a lower final attenuation limit.Worts from this variety excelled with lower β-glucans content and higher pH results. Very low turbidity of sweet wort during lautering and hopped wort during cooling correlated with perfect clarity of congress wort. Excellent filterability in full-scale trial was found out. Tannoid content in cold wort of Bojos was higher than the one of Tolar variety. A tannoid content and SASPL number in packaged beer corresponded to the required colloidal stability. Testing panels did not find any significant differences.The pilot plant and full-scale trials were made with malts from barley varieties Bojos and Tolar.The wort and beer were analysed to find out whether Tolar variety could be substitute for Bojos variety. Bojos variety had a very good wort extract, lower content of β-glucans and a perfect wort clarity. The results of Hartong VZ 45 °C, FAN and final attenuation were on the similar level as Tolar variety. Contents of fermentable sugars and dextrins in worts from Bojos and Tolar were very similar. Bojos variety proved a lower final attenuation limit.Worts from this variety excelled with lower β-glucans content and higher pH results. Very low turbidity of sweet wort during lautering and hopped wort during cooling correlated with perfect clarity of congress wort. Excellent filterability in full-scale trial was found out. Tannoid content in cold wort of Bojos was higher than the one of Tolar variety. A tannoid content and SASPL number in packaged beer corresponded to the required colloidal stability. Testing panels did not find any significant differences