679 research outputs found

    Tinjauan Pengembangan Landasan Pacu Bandar Udara Kasiguncu Kabupaten Poso

    Get PDF
    Means of airport for landing and take off of aircraft is runway. This writing to determine the direction of runway according to aircraft that serviced, geometric requirements of existingrunway conditions in 2011 and the development of phase II stage 2 in 2030 and runway pavement thickness existing conditions in 2011 and the development of phase II stage 2 in 2030. Method that used to determine the direction of the runway using the wind rose and for geometric runway using the ICAO and FAA as well as for runway pavement thickness using the FAA.From the wind analysis result using the wind rose, the direction of the existing runway 03-21 can be used safely. From the calculation result of the geometric condition of existing runway length obtained in 2011 by ICAO runway at for the Fokker F-28 aircraft while the width of the runway by ICAO and FAA at 30,48 m. The condition of the existing runway has a runway length 1.617 m and a width 30 m, so that the runway has been unable to serve the aircraft.For the conditions of the development of phase II stage 2 in 2030 acquired by the FAA runway length at 2.070 m and width 30,48 m while the length of the runway by ICAO at 2.704 m and a width 45,72 m. Conditions runway geometric phase II development stage 2 has a length 2.100 m and a width 45 m, so the runway is capable of servicing Boeing 737-300 aircraft safely compared with FAA planning method. From the calculation result of runway pavement thickness existing conditions in 2011 earned a total pavement thickness is 38 cm with aircraft plan Xian MA-60. Condition of existing runway has a total pavement thickness is 87 cm so that the Xian MA-60 aircraft can be served safely. For the conditions of the development of phase II stage 2 obtained after the equivalent total pavement thickness is 69,5 m for model 1 and 68,8 cm for the model 2 with aircraft plan Boeing 737-300. Conditions runway development phase II stage 2 has a totalpavement thickness after the equivalent is 77,5 cm, so the Boeing 737-300 aircraft can be served safely

    A Loop Region in the N-Terminal Domain of Ebola Virus VP40 Is Important in Viral Assembly, Budding, and Egress

    Get PDF
    Ebola virus (EBOV) causes viral hemorrhagic fever in humans and can have clinical fatality rates of ~60%. The EBOV genome consists of negative sense RNA that encodes seven proteins including viral protein 40 (VP40). VP40 is the major Ebola virus matrix protein and regulates assembly and egress of infectious Ebola virus particles. It is well established that VP40 assembles on the inner leaflet of the plasma membrane of human cells to regulate viral budding where VP40 can produce virus like particles (VLPs) without other Ebola virus proteins present. The mechanistic details, however, of VP40 lipid-interactions and protein-protein interactions that are important for viral release remain to be elucidated. Here, we mutated a loop region in the N-terminal domain of VP40 (Lys127, Thr129, and Asn130) and find that mutations (K127A, T129A, and N130A) in this loop region reduce plasma membrane localization of VP40. Additionally, using total internal reflection fluorescence microscopy and number and brightness analysis we demonstrate these mutations greatly reduce VP40 oligomerization. Lastly, VLP assays demonstrate these mutations significantly reduce VLP release from cells. Taken together, these studies identify an important loop region in VP40 that may be essential to viral egress

    Protein and energy requirements for indigenous guinea keets (Numida meleagris) in southern Ghana

    Get PDF
    One thousand two hundred healthy unsexed unsexed keets were used in an 8-week feeding trial that aimed at determining the protein and energy requirements during the starter phase of local guinea fowls reared in coastal savanna part of Ghana. The keets were randomly allocated in a 3 X 2 factorial design to six dietary treatments (three crude protein levels and two energy levels) in a deep litter system. Each treatment had 200 keets and was replicated four times with 50 keets per replicate. The six dietary treatments were designated as follows: T1 (23% CP and 11.5 MJ ME/kg), T2 (24% CP and 11.5 MJ ME/kg), T3 (25% CP and 11.5 MJ ME/kg), T4 (23% CP and 12.5 MJ ME/kg), T5 (24% CP and 12.5 MJ ME/kg), and T6 (25% CP and 12.5 MJ ME/kg). A known daily quantity of feed was given each replicate early in the morning while water was provided ad libitum. The same diets were fed for the entire duration of the study. Feed intake, weight gain, feed conversion ratio, economy of gain and mortality were determined and use as indices of evaluation. The feed intake per keet per day increased with the lower energy level diets (T1, T2 and T3) (P < 0.05). Dietary treatments T5 and T6 had the highest (P < 0.05) daily weight gains of 8.61 and 8.38 g/day respectively. The feed conversion ratios of the keets were 4.18, 4.20, 4.13, 4.32, 3.46 and 3.60 for T1, T2, T3, T4, T5 and T6, respectively. T5 diet had the least (P < 0.05) feed costs per kg gain ($/kg gain) value of 1.63. The study indicated that protein and energy required by guinea keets during the first 8 weeks of growth could be put at 24 percent CP and 12.5 MJ ME/kg, respectively

    Understanding environmental incidents on construction sites in Australia: The causal factors, environmental impact and their relations

    Get PDF
    The construction sites are prone to environmental incidents. In this paper, the root causes of incidents and immediate actions taken after events are identified through qualitative analysis, while the environmental impacts, the cost of mitigation, time of incident occurrence, as well as the relationship between the causes of incidents and immediate actions and the causes and environmental impacts were quantitatively analysed. In total, 499 environment incidents occurred over an 8-year period on the construction sites in Australia was examined in this study. The results show that the most common causes of incidents were equipment and plant failure, oil spillage, and fuel spillage, while the most expensive incidents in terms of mitigation were flooding, poor weather, and process failures. Further, the most common actions taken immediately after incidents were cleaning and clearing, shut down of operation, plant and equipment and notifications. More than 50% of incidents resulted in the contamination of land and groundwater, while the majority of incidents occurred between 10:00 am and 12:00 am. We propose strategies for project managers and environmental managers to better understand potential environmental hazards

    Variation in the export of 13C and 15N from soybean leaf: the effects of nitrogen application and sink removal

    Get PDF
    Translocation of carbon and nitrogen within a single source-sink unit, comprising a trifoliated leaf, the axillary pod and the subtending internode, and from this unit to the rest of the plant was examined in soyabean (Glycine max L. cv. Akishirome) plant by feeding 13CO2 and 15NO3. The plants were grown at two levels of nitrogen in the basal medium, i.e. low-N (2 g N m-2) and high-N (35 g N m-2) and a treatment of depodding was imposed by removing all the pods from the plant, except the pod of the source sink unit, 13 days after flowering. The plants at high-N accumulated more biomass in its organs compared to low-N and pod removal increased the weight of the vegetative organs. When the terminal leaflet of the source-sink unit was fed with 13CO2, almost all of the radioactive materials were retained inside the source-sink unit and translocation to rest of the plants was insignificant under any of the treatments imposed. Out of the 13C exported by the terminal leaflet, less than half went into the axillary pod, as the lateral leaflets claimed equal share and very little material was deposited in the petiole. Pod removal decreased 13C export at high-N, but not at low-N. Similar to 13C, the source-sink unit retained all the 15N fed to the terminal leaflet at high-N. At low-N, the major part of 15N partitioning occurred in favour of the rest of the plant outside the source-sink unit, but removal of the competitive sinks from the rest of the plants nullified any partitioning outside the unit. Unlike the situation in 13C, no partitioning of 15N occurred in favour of the lateral leaflets from the terminal leaflet inside the unit. It is concluded that sink demand influences partitioning of both C and N and the translocation of carbon is different from that of nitrogen within a source-sink unit. The translocation of the N is more adjustive to a demand from other sink units compared to the C

    Determining the electronic performance limitations in top-down fabricated Si nanowires with mean widths down to 4 nm

    Get PDF
    Silicon nanowires have been patterned with mean widths down to 4 nm using top-down lithography and dry etching. Performance-limiting scattering processes have been measured directly which provide new insight into the electronic conduction mechanisms within the nanowires. Results demonstrate a transition from 3-dimensional (3D) to 2D and then 1D as the nanowire mean widths are reduced from 12 to 4 nm. The importance of high quality surface passivation is demonstrated by a lack of significant donor deactivation, resulting in neutral impurity scattering ultimately limiting the electronic performance. The results indicate the important parameters requiring optimization when fabricating nanowires with atomic dimensions

    Thermal effects on electron-phonon interaction in silicon nanostructures

    Full text link
    Raman spectra from silicon nanostructures, recorded using excitation laser power density of 1.0 kW/cm^2, is employed here to reveal the dominance of thermal effects at temperatures higher than the room temperature. Room temperature Raman spectrum shows only phonon confinement and Fano effects. Raman spectra recorded at higher temperatures show increase in FWHM and decrease in asymmetry ratio with respect to its room temperature counterpart. Experimental Raman scattering data are analyzed successfully using theoretical Raman line-shape generated by incorporating the temperature dependence of phonon dispersion relation. Experimental and theoretical temperature dependent Raman spectra are in good agreement. Although quantum confinement and Fano effects persists, heating effects start dominating at higher temperatures than room tempaerature.Comment: 9 Pages, 3 Figures and 1 Tabl

    Mass and metallicity scaling relations of high-redshift star-forming galaxies selected by GRBs

    Get PDF
    We present a comprehensive study of the relations between gas kinematics, metallicity and stellar mass in a sample of 82 gamma-ray burst (GRB)-selected galaxies using absorption and emission methods. We find the velocity widths of both emission and absorption profiles to be a proxy of stellar mass. We also investigate the velocity–metallicity correlation and its evolution with redshift. Using 33 GRB hosts with measured stellar mass and metallicity, we study the mass–metallicity relation for GRB host galaxies in a stellar mass range of 108.2–1011.1 M⊙ and a redshift range of z ∼ 0.3–3.4. The GRB-selected galaxies appear to track the mass–metallicity relation of star-forming galaxies but with an offset of 0.15 towards lower metallicities. This offset is comparable with the average error bar on the metallicity measurements of the GRB sample and also the scatter on the mass–metallicity relation of the general population. It is hard to decide whether this relatively small offset is due to systematic effects or the intrinsic nature of GRB hosts. We also investigate the possibility of using absorption-line metallicity measurements of GRB hosts to study the mass–metallicity relation at high redshifts. Our analysis shows that the metallicity measurements from absorption methods can significantly differ from emission metallicities and assuming identical measurements from the two methods may result in erroneous conclusions

    White Matter Integrity and Processing Speed in Sickle Cell Anemia

    Get PDF
    Objective The purpose of this retrospective cross-sectional study was to investigate whether changes in white matter integrity are related to slower processing speed in sickle cell anemia. Methods Thirty-seven patients with silent cerebral infarction, 46 patients with normal MRI, and 32 sibling controls (age range 8–37 years) underwent cognitive assessment using the Wechsler scales and 3-tesla MRI. Tract-based spatial statistics analyses of diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) parameters were performed. Results Processing speed index (PSI) was lower in patients than controls by 9.34 points (95% confi- dence interval: 4.635–14.855, p = 0.0003). Full Scale IQ was lower by 4.14 scaled points (95% confidence interval: −1.066 to 9.551, p = 0.1), but this difference was abolished when PSI was included as a covariate (p = 0.18). There were no differences in cognition between patients with and without silent cerebral infarction, and both groups had lower PSI than controls (both p < 0.001). In patients, arterial oxygen content, socioeconomic status, age, and male sex were identified as predictors of PSI, and correlations were found between PSI and DTI scalars (fractional anisotropy r = 0.614, p < 0.00001; r = −0.457, p < 0.00001; mean diffusivity r = −0.341, p = 0.0016; radial diffusivity r = −0.457, p < 0.00001) and NODDI parameters (intracellular volume fraction r = 0.364, p = 0.0007) in widespread regions. Conclusion Our results extend previous reports of impairment that is independent of presence of infarction and may worsen with age. We identify processing speed as a vulnerable domain, with deficits potentially mediating difficulties across other domains, and provide evidence that reduced processing speed is related to the integrity of normal-appearing white matter using microstructure parameters from DTI and NODDI

    The modern pollen-vegetation relationship of a tropical forest-savannah mosaic landscape, Ghana, West Africa

    Get PDF
    Transitions between forest and savannah vegetation types in fossil pollen records are often poorly understood due to over-production by taxa such as Poaceae and a lack of modern pollen-vegetation studies. Here, modern pollen assemblages from within a forest-savannah transition in West Africa are presented and compared, their characteristic taxa discussed, and implications for the fossil record considered. Fifteen artificial pollen traps were deployed for 1 year, to collect pollen rain from three vegetation plots within the forest-savannah transition in Ghana. High percentages of Poaceae and Melastomataceae/Combretaceae were recorded in all three plots. Erythrophleum suaveolens characterised the forest plot, Manilkara obovata the transition plot and Terminalia the savannah plot. The results indicate that Poaceae pollen influx rates provide the best representation of the forest-savannah gradient, and that a Poaceae abundance of >40% should be considered as indicative of savannah-type vegetation in the fossil record
    • …
    corecore