572 research outputs found

    MSL Entry, Descent and Landing Performance and Environments

    Get PDF
    A viewgraph presentation on the MARS Science Laboratory (MSL) Entry, Descent and Landing (EDL) performance and environments is shown. The topics include: 1) High Altitude and Precision Landing; 2) Guided, Lifting, Ballistic Trade; 3) Supersonic Chute Deploy Altitude; 4) Guided, Lifting, Ballistic Landing Footprint Video; 5) Transition Indicator at Peak Heating Point on Trajectory; 6) Aeroheating at Peak Heating Point on Trajectory Nominal, No Uncertainty Included; 7) Comparison to Previous Missions; 8) Pork Chop Plots - EDL Performance for Mission Design; 9) Max Heat Rate Est (CBE+Uncert) W/cm2; 10) Nominal Super Chute Deploy Alt Above MOLA (km); 11) Monte Carlo; 12) MSL Option M2 Entry, Descent and Landing; 13) Entry Performance; 14) Entry Aeroheating and Entry g's; 15) Terminal Descent; and 16) How An Ideal Chute Deployment Altitude Varies with Time of Year and Latitude (JSC Chart)

    Redundant roles of the phosphatidate phosphatase family in triacylglycerol synthesis in human adipocytes.

    Get PDF
    AIMS/HYPOTHESIS: In mammals, the evolutionary conserved family of Mg(2+)-dependent phosphatidate phosphatases (PAP1), involved in phospholipid and triacylglycerol synthesis, consists of lipin-1, lipin-2 and lipin-3. While mutations in the murine Lpin1 gene cause lipodystrophy and its knockdown in mouse 3T3-L1 cells impairs adipogenesis, deleterious mutations of human LPIN1 do not affect adipose tissue distribution. However, reduced LPIN1 and PAP1 activity has been described in participants with type 2 diabetes. We aimed to characterise the roles of all lipin family members in human adipose tissue and adipogenesis. METHODS: The expression of the lipin family was analysed in adipose tissue in a cross-sectional study. Moreover, the effects of lipin small interfering RNA (siRNA)-mediated depletion on in vitro human adipogenesis were assessed. RESULTS: Adipose tissue gene expression of the lipin family is altered in type 2 diabetes. Depletion of every lipin family member in a human Simpson-Golabi-Behmel syndrome (SGBS) pre-adipocyte cell line, alters expression levels of adipogenic transcription factors and lipid biosynthesis genes in early stages of differentiation. Lipin-1 knockdown alone causes a 95% depletion of PAP1 activity. Despite the reduced PAP1 activity and alterations in early adipogenesis, lipin-silenced cells differentiate and accumulate neutral lipids. Even combinatorial knockdown of lipins shows mild effects on triacylglycerol accumulation in mature adipocytes. CONCLUSIONS/INTERPRETATION: Overall, our data support the hypothesis of alternative pathways for triacylglycerol synthesis in human adipocytes under conditions of repressed lipin expression. We propose that induction of alternative lipid phosphate phosphatases, along with the inhibition of lipid hydrolysis, contributes to the maintenance of triacylglycerol content to near normal levels.This study was supported by research grants from the ‘Instituto de Salud Carlos III’ (ISCIII, Spanish Ministry of Economy and Competitiveness) (PI10/00967 and CP11/0 0021 to MM); the R. Barri Private Foundation (PV12142S to MM); the Medical Research Council (G0701446 to SS); and National Institutes of Health Grant (GM028140 to GMC). CIBER de Diabetes y Enfermedades Metabólicas asociadas (CB07708/0012) is an initiative of the ISCIII. MM acknowledges support from the ‘Miguel Servet’ tenure track programme (CP11/00021), from the Fondo de Investigación Sanitaria (FIS) co-financed by the European Regional Development Fund (ERDF), and supported by a Salvador de Madariaga Mobility fellowship from the Spanish Ministry of Education (PR2011-0584). AT is the recipient of a FI-DGR fellowship (9015-97318/2012) from the Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR)This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by Springer

    The brown adipocyte protein CIDEA promotes lipid droplet fusion via a phosphatidic acid-binding amphipathic helix

    Get PDF
    Maintenance of energy homeostasis depends on the highly regulated storage and release of triacylglycerol primarily in adipose tissue, and excessive storage is a feature of common metabolic disorders. CIDEA is a lipid droplet (LD)-protein enriched in brown adipocytes promoting the enlargement of LDs, which are dynamic, ubiquitous organelles specialized for storing neutral lipids. We demonstrate an essential role in this process for an amphipathic helix in CIDEA, which facilitates embedding in the LD phospholipid monolayer and binds phosphatidic acid (PA). LD pairs are docked by CIDEA trans-complexes through contributions of the N-terminal domain and a C-terminal dimerization region. These complexes, enriched at the LD–LD contact site, interact with the cone-shaped phospholipid PA and likely increase phospholipid barrier permeability, promoting LD fusion by transference of lipids. This physiological process is essential in adipocyte differentiation as well as serving to facilitate the tight coupling of lipolysis and lipogenesis in activated brown fat

    Examining the joint effects of strategic priorities, use of management control systems, and personal background on hospital performance

    Get PDF
    This study aims to respond to recent calls for a better understanding of the factors that support the effectiveness of formal control practices in hospitals. Based on survey data from 117 top-level managers in Belgian hospitals, the study investigates the performance effects of the alignment between the use of performance measurement systems (PMS), strategic priorities, and the particular role top-level managers’ personal background plays in this context. The quantitative results suggest that it is the top-level managers’ personal background that brings to life the benefits of the alignment between the use of PMS and strategic priorities in hospitals. Specifically, this paper shows that when the emphasis on partnership or governance strategic priority is high, the effect of the interactive use of PMS on hospital performance is more positive for top-level managers with a clinical background than for those with an administrative background. This study offers value for practitioners in that it supports the argument that hospitals can benefit from involving physicians in the top-level management team

    Modelling of the effect of ELMs on fuel retention at the bulk W divertor of JET

    Get PDF
    Effect of ELMs on fuel retention at the bulk W target of JET ITER-Like Wall was studied with multi-scale calculations. Plasma input parameters were taken from ELMy H-mode plasma experiment. The energetic intra-ELM fuel particles get implanted and create near-surface defects up to depths of few tens of nm, which act as the main fuel trapping sites during ELMs. Clustering of implantation-induced vacancies were found to take place. The incoming flux of inter-ELM plasma particles increases the different filling levels of trapped fuel in defects. The temperature increase of the W target during the pulse increases the fuel detrapping rate. The inter-ELM fuel particle flux refills the partially emptied trapping sites and fills new sites. This leads to a competing effect on the retention and release rates of the implanted particles. At high temperatures the main retention appeared in larger vacancy clusters due to increased clustering rate

    Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

    Get PDF
    The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR
    corecore